Concepts: Animalia (Vertebrates)
Vertebrates are those which are mobile, bear a true vertebrate column and muscular body where internal skeleton gives them a structural frame, are bilateral symmetrical, triploblastic coelomates, containing well differentiated tissues and organs with closed circulatory system.
Classification of vertebrates-
Pisces: All fishes are in this class, are cool-blooded, containing a heart with two chambers and are water loving. Their bodies are covered with scales or plates. Gills are their respiratory organ, which uses water dissolving oxygen. They have a tail made up of muscles used for body movement. They lay eggs. Their skeletons are either consisting of only cartilage (sharks) or both bone and cartilage (Labeorohita).
Amphibia: These organisms live in both aquatic and terrestrial habitats. Their skin has mucus glans. They contain a heart with three chambers. Unlike fish, they have no scales to cover themselves. Respiration occurs through either gills or lungs depending on their life stages. They lay eggs (lacking shell) in water. For example, frogs, salamander etc.
Reptilia: They are the cool-blooded animals, as they cannot control own body temperature, with a heart of three chambers (crocodiles are the exception containing four chambered heart). Scales are present on their body, lungs are their respiratory organ, lay eggs on land with a tough shell, for example-snakes.
Aves: All birds are included in this class, are worm-blooded means they control their body temperature, containing a heart with four chambers, can fly due to present of two wings, have feathers which covered their whole body, laying eggs, lungs are their respiratory organ.
Mammalia: These are the warm-blooded, as they can maintain their body temperature. They have a heart which is divided into four chambers for proper circulation, containing mammary glands responsible for milk production, sweat and oil glands are located in their skin with bearing hairs, give birth to whole organism (echidna and platypus are the exception both are laying eggs, and kangaroos are giving birth to an immature weaken young one) for example Human, Whale etc.
Concept: Animalia (Invertebrates)
In this group, organisms are multicellular, heterotrophs & might be mobile or non-mobile.
These organisms are classified into-
Porifera are mere differentiated organisms with a rigid outer surface attached to a support (non-motile). The whole organism is bearing pores, which is responsible for circulation of water and nutrients in a canal system. For example, Spongilla.
Coelenterates are comparatively better, differentiation of their body exists as body cavity is present, consisting of double layered cells (outer and inner lining). They are found in water. Some live-in colonies, like corals, and in solitary (like Hydra and jellyfish).
Platyhelminthes are comparatively complex, and having differentiated tissues, consisting of three layers of cells. So, they are called triploblastic. Their body has bilateral symmetry and flattened body (knows as flatworm), lacking true internal body cavity and organs. They are either free living (example-planarians) or parasites (example-liver flukes).
Nematodes are of cylindrical shaped ,bilateral symmetrical and triploblastic, and have a body cavity like material. They are called pseudo-coelom but lacks true organs. Example elephantiasis disease is caused by filarial worms, round worms (Ascaris) casing intestine illness.
Annelida is a group of animals, which are bilaterally symmetrical, triploblastic, ring like segmented appearance, containing true body cavity and differentiated organs. Example, earthworms and leeches belong to this group.
Arthropoda means jointed foot, have bilateral symmetry, segmented appearance. They have coelomic cavity filled with blood due to open circulatory system (blood do not flow through blood-vessels). Examples are mosquitoes, spiders etc. It is the largest phylum.
Mollusca have bilateral symmetry, little segmented, containing reduced coelomic cavity and open circulatory system, containing excretion organs, motile as bare foot. Examples are snails, mussels.
Echinodermata are the triploblastic coelomates, bearing spiny outer skin, a peculiar water-driven tube system. They are free living mobile marine animals, having a hard skeleton made up of calcium carbonate. For example-starfish.
Protochordata are bilaterally symmetrical, triploblastic coelomates, forming a flexible rod like notochord which is also found in embryo of vertebrates, found in marine water. For example-Balanoglossus.
Concept: Diversity
Diversity means variety. It has been shown how much an organism is diverse from other organisms. If two different organisms have many similar characteristics with each other, it would be considered that both may have derived from a common ancestor. For example, let us compare a human with a chimpanzee and a cow. It is found that there are many similarities between a human and a chimpanzee compared to similarities between a human and a cow. So, we conclude that chimpanzee and human somehow derive from a common ancestor.
This diversity has been possible due to a series of mutation or adaptation. If we look around us, we will see that there are a lot of organisms which not only differ in their looks, but also vary in their shape and size. They are not identical with each other. For example, there are some groups of single celled microscopic bacteria, which are of only about a few micrometers in size. On the other hand , 100 meters of red wood trees are also present on earth. Both not only differ in their size, also vary greatly in their cellular mechanism. For example, unlike multicellular organisms, single celled bacteria have no membrane bound organelles and nuclear membrane around their genetic materials.
Not only that, varieties of multicellular organisms like animal cells and plant cells are highly diverse with each other. Plant cells can do photosynthesis whereas animal cells, due to lake of chlorophyll pigment, cannot do photosynthesis.
Concept: Evolution and Classification
Evolution is a process where a primitive organism gets modified into a complex or an advance organism through a series of accumulation of irreversible changes in their characteristics. This happens due to mutation or adaptation which helps an organism to become a better survivor.
When two organisms get separated due to some reason and and are not further involved in breeding process, they are considered as two distinct species.
The classification of organism is very important because it would have not been possible to notice different characteristic features of each and every organism without classification. The Whittaker classification is widely accepted where he classified organisms on the basis of their structure, nutritional type, and their body organization. According to his classification, he grouped a large number of organisms into 5 broad categories (kingdoms)-
Monera: Here unicellular organisms like bacteria, cyanobacteria and mycoplasma are included in this kingdom. Some of them have cell wall and some have not. Autotrophs (able to make their own food) or heterotrophs (unable to make their own food)are two different kinds of nutritional modes.
Carl Woese further divides this Monera kingdom into Archaebacteria ( having advanced organisms like thermophiles and psychrophiles)and Eubacteria (having normal bacteria, Bacillus, E.coli)
Protista: In this kingdom of unicellular eukaryotic, some organism like diatoms, protozoa and algae are involved. They have some hairy structure on their surface like cilia and flagella, which allows them to move. Their mode of nutrition can either be autotrophs or heterotrophs.
Fungi: Fungous is a type of eukaryotic multicellular saprophytic organism which takes nutrients from dead, decay matter. They have a cell wall composed of chitin. Some fungi make a symbiotic relationship with algae.
Plantae: All plants are belonging to this kingdom. They all are eukaryotic multicellular autotrophic organisms with thick cell wall, generally made of cellulose, and are non-motile in nature.
Animalia: All animals are included to this kingdom. They all are multicellular heterotrophic eukaryotes with no cell wall and greater motility.
These groups of organisms are further divided into sub-groups: Kingdom, Phylum/Division, Class, Order, Family, Genus and Species.
Concept: Plantae
The kingdom of plantae includes all the plants. It is further classified into following groups:
Thallophyta: Aquatic algae are included in this group. They have no differentiated tissues, stem, and roots; therefore, they cannot conduct minerals and water from place to place.
Bryophyta: They are the amphibians of the plantae kingdom because they have plant like differentiated stem and roots but does not have any tissue that conduct minerals and water through it. For example , moss.
Pteridophyta: They contains plant like leaves, stem, and roots but their reproductive organs are not isolated. Due to this reason, they are also called cryptogamae which means they have some hidden reproductive organs. It has been shown that they produce spores. For example, ferns.
Depending on whether a plant bear naked seed or covered seed, it is classified into these two groups-
Gymnosperms: Plants of perennial are belonging to this group where plants produce naked seed, which through germination process produces a new individual plant. For example, pine tree.
Angiosperms: All flowering plants are included in this group, where plants produce seed enclosed in fruits. During germination, these fruits provide nutrients to the embryo. Depending on the structure of the seeds, it is divided into- monocotyledon (has a single cotyledon like corn, palm) and dicotyledon (has two cotyledons like peal, gram).
Concept: Cell organelles
Eukaryotic cells are more complex to that of Prokaryotic cell so constituents’ greater cellular organization. The cell constituents single or double layered organelles like lysosome, vacuole, Golgi apparatus, endoplasmic reticulum is Single layered. Mitochondria and chloroplast are double membrane bound organelles in a cell.
Endoplasmic reticulum (ER) is a large membranous network system arranging in tubular sheets. The ER is the extended version from the nucleus membrane. It is of two type the Rough ER and the Smooth ER. The rough ER has the ribosomes embedded in its outside and is responsible for protein synthesis, on the other hand the Smooth ER has no ribosome in it and is responsible for lipid synthesis and sometimes for material detoxification.
Golgi apparatus is a membrane bound structure responsible for packaging and transportation of material in and outside the cell. The processed protein from the ER enters Golgi apparatus from there they are loaded in vesicles and are transported across the cell. The disc like projection in Golgi apparatus and ER is known as Cisternae.
Lysosomes is an important organelle responsible for cleaning of the cell. It contains hydrolytic enzymes so maintains an acidic pH which degrades the useless materials of the cell. It sometime can digest the cells own old organelles if not in use. The leakage of these hydrolytic enzymes can kill the self-cell so is regarded as the Suicidal bag of the cell.
Mitochondria is said to be the powerhouses of the cell because they produce ATP molecules in its inner membrane called Cristae. It carries its own DNA and ribosomes, surrounded by two membranes so, is known as autonomous organ of the cell. The prokaryotic cell lack mitochondria and their ATP synthesis takes place in the plasma membrane.
Plastids are found mostly in the plant cells carrying their own DNA and ribosomes and are the other autonomous organ of the cell. Basically, two types of plastids are found- chromoplasts (contained pigments) and leucoplast (absent pigments) and is used for storage. Chloroplast is such a plastid that contains chlorophyll pigment necessary for photosynthesis.
Vacuoles are the solid or liquid storage sacs found in plant or some animal cells like Amoeba stores food materials. Plants have been centrally located larger vacuoles than animal vacuoles. Some organism uses these for expelling excess water and wastes from the cell.
Concept: Discovery of the cell
Antony van Leeuwenhoek observed some single celled organisms under his self-made microscope. He named these organisms as ‘animalcules. Then Robert Hook was one of the first people who showed the small, microscopic cavities in a cork under microscope and named these things as ‘boxes cells. Cell means ‘a little room’.
All living organisms that we see around us are originated from a single cell. The organisms which are having single cell are called unicellular organism such as bacteria. On the other hand, by when more than one cells are grouped together to make up an organism for are called multicellular organisms. For example, fungi, plants, and animals, etc.
Some organisms for example in human being also have different kinds of cells like blood cells, nerve cells, bone cells, smooth muscle cells, sperms, ovum etc. all are not only differ in their structure but also have some specific functions that are differ from each other such as a heart consisting of cardiac cells which allow heart to pump blood, a stomach help to digest food, nerve cell allow to transmit electrical impulsion and so on.
Some cells for example Amoeba are a single animal cell (protozoa) which is able to alter their cell shape due to lake of any rigid cell wall like covering. Their movement also called amoeboid movement.
Concept: Structure of the cell
The cell is the basic building block of the body, and the constituents of cell are as follows:
Plasma membrane: The outer covering of a cell which separates it from the outer environment. It is semi-permeable in nature i.e. it only allows the entry of selectable constituents through it.
Diffusion: It is a process in which molecules move from higher to the lower concentration i.e. towards the concentration gradient without the need of energy across the plasma membrane. Example- gases like CO2 and O2 diffusion.
Osmosis: The water moves from higher to lower solution concentration this process, known as osmosis. This thing has been observed in all living cell where in hypotonic solution (higher the outer solution concentration compare to the inner cell concentration) cell get swell up due to inward movement of water, in isotonic solution (equal concentration of both outer and inner solution) cell remain same and in hypertonic solution (lower the outer solution concentration compare to the inner cell concentration) cell get shrink. The shrinkage of a living cell due to lose of water through osmosis is called plasmolysis.
Cell wall: A thick rigid cover present external to the cell membrane is known as Cell wall. It is responsible for the shape of the cell and is permeable to all cell constituents. For example, plants have a rigid cell wall consists of cellulose. Animal cell lack Cell wall.
Nucleus: It is a double membrane bound round shaped structure has some pores allowing materials to move in or out, contains nucleic acid. Due to absent of nuclear membrane in case of prokaryotes there are a region that contains their nucleic acid is called nucleoid.
Cytoplasm: The gel like portion present internal of the cell membrane constituents all the cell organelles in it is
called cytoplasm. But prokaryotes lack membrane bound organelles like mitochondria, plastid etc.
Concept: Animal Husbandry (Cattle and poultry farming)
Animal husbandry is a management of for animal livestock where breeding, caring, and managing of animals occurs in a scientific way. Animals are raised for meat, milk, eggs, or other products and some are used for as labor in agricultural work.
Cattle farming:
Cattles are used for mainly two purposes, producing milk (produce milk by milk-producing females are known as milch or dairy animals) and draught labor (used for farm labor known as draught animals). There are two different species belonging to Indian species- Bosindicus (Cows) and Bosbubalis (buffaloes). Crossbreeding also occurs between two different animals, yielding a cross-bred animal containing desirable qualities derived from two different species. For example, Jersey (foreign breed) produces huge milk and Red Sindhi (local breed) has excellent resistant properties to disease.
For keeping cattle healthy and disease free, it is necessary to give them proper food (roughage and concentrates have low amount of fibre, high amount of proteins and other minerals), clean their shelter regularly and brushing them regularly.
Due to poor management, cattle can suffer from various diseases like skin disease (responsible for external parasites) & liver damage (responsible for internal parasites). For fighting against viral and bacterial diseases, they should be given vaccination and antibiotics.
Poultry farming:
Poultry farming means taking care of domestic fowl for egg production and chicken meat. Different Poultry breeds are produced, such as layers for egg production and broilers for meat production. Crossbreeding also takes place between Aseel (Indian) and Leghorn (foreign), which produces new varieties.
For good growth, broiler chickens require vitamin-rich supplementary feed. For good health and production, poultry birds should be kept under hygienic conditions. Appropriate temperature should be maintained, , proper cleaning, sanitation and spraying of disinfectants should be done at regular interval.
Poultry fowl also suffer from some viral, bacterial, fungal, and parasitic disease. Thus, they should be given appropriate vaccines ,antibiotics etc. to fight against such disease. This reduces loss of poultry from death.
Concept: Animal husbandry (Fish production and Beekeeping)
Fish production:
Fish is a common source of protein. The production of fish includes both, finned true fish and shellfish which are obtained in two ways. One is by Capture fishing where fishes are caught from their natural resources, and other is by Culture fishery which includes fish farming. Culture fishery is done of various selected fishes only for the reason of getting food and other products.
Marine fishery is a type of fish farming in seawater. Pomfrets, Tuna and some other fishes are used for cultivation. Fishing nets are used for catching fishes. For increasing yields, some advanced techniques like satellites and echo-sounders are used to determine large schools of fish in the open sea.
Some finned fishes like mullets, pearl spots etc. and some shellfish like prawns, oysters (are cultivated for the pearls)etc. have high economic value. The culture of such marine organisms for getting food and many more products is called Mariculture.
Inland fishery is the process of cultivating fish in freshwater( like ponds, rivers etc.) and brackish water (where seawater and freshwater mix together). Paddy Cum Fish Culture (PFC) is a one type of fish culturing in the water of rich field.
Composite fish culture is another type of fish farming, where five to six types of fishes ( belonging to different species and differing in their nutritional requirement, so they do not fight with each other for same food) are cultured in same pond. Due to some limitation of this method, some particular varieties only can be found
Beekeeping:
Beekeeping is management of breeding and rearing of bees for their honey and wax, derived from their beehives. There are huge variations in the types of bees found . For market production- Apiscerana indica (Indian bee), rock bee, little bee, and Italian bee (A. mellifera) are used ,but among them Italian bees have highest capacity to collect honey.
The quality and taste of the honey depends on the quality of flowers; thus, it is important to notice what kind of flowers are available to bees.
Concept: Improvement in crop production
The aspects important to undergo a farming are as follows:
Nutritional requirement: Plants have adequate demands for nutrients for their survival. Plants require two types of nutrients:
Macronutrients – C, O, H, N, K, P etc. which are required in larger amount as they have greater demand for metabolism by the plants
Micronutrients – Zn, Br, Cu etc. are required in small amount, having specific role in reactions (Co-factors).
All of these are required to prevent the nutrient deficiency of the plant and get higher crop yield.
Manure is a natural way to maintain soil fertility as the soil is enriched by organic matter. This includes the organic wastes of the house (hay, vegetable peels, excreta etc.). It is carried out by two ways-
In the village areas where the framing is done a pit is dug which is filled with organic wastes, human excreta, cow dung, vegetable peels, farm wastes etc. It might be covered or left opened. This process (open and closed compost) is known as Composting. It is left for moths to be converted into simpler form, by the microbes, and are later used in the field to increase the fertility of the soil. The compost is sometimes enriched with earthworms. It is then known as Vermicompost. Earthworms are required for proper mixing of compounds with the soil and is called Farmers’ Friend.
Some plants are sometimes left uprooted or are sometimes grown in the land to enrich the nutrient levels, for example, enrich the nitrogen or phosphorus concentration . It is called Green manure. Example of such plant includes, Sunn hemp, Soybean etc.
This is a way of Organic farming, which includes manures, bio-fertilizers, bio-pesticides. Neem leaves and turmeric are used for the storage of grain.
Fertilizers are chemically synthesized products , which are rich in nitrogen, potassium, and phosphorus. It is added to increase the fertility of the soil in an adequate amount so that the plant does not suffers from the deficiency of the macronutrients. But excessive use of fertilizer cause water pollution, destroy the soil structure and soil fertility by locking the pores of the soil.
Irrigation: Supplying adequate water to the cropping field is known as irrigation. It includes Drip irrigation or Sprinkler Irrigation.
Cropping patterns: Crop rotation is the process in which different plants with different nutrient demands are grown in the same field.
Concept: Improvement in food resources
Food is the basic need for all the metabolism to occur in a body. Plant, Human or Microscopic organisms, all need food. India, being the second highest in the population level, has a high food demand for sustaining lives.
Agriculture is the branch of science which involves crops, vegetables, fruits etc. cultivations, breeding, and rearing of livestock. Animal husbandry is the branch of agriculture in which animals are reared and selectively bred according to human demand for protein sources like milk, egg, meat.
Rice, wheat etc. are source of carbohydrates and are responsible for providing energy. Pulses are great source of protein supplements. Fats and required lipid content are supplied by oil seeds and even by Fish & Cod liver oil.
Vitamins and minerals are supplied by vegetables, spices, and fruits . Fodder crops like oats, grass, Brassica are the food sources for livestock.
There are two types of crops, divided by the seasons it grows in:
Rabi Crops: Crops that are grown during the winter season are known as Rabi Crops. For example, pea, mustard, wheat etc.
Kharif Crops: Crops that are grown at the rainy season are known as Kharif Crops. For example, maize, paddy , cotton etc.
For the required increase of the crop output, things that should improve are-
Crop variety improvement is important to grow better crops. It includes development of disease resistant crops, abiotic resistance with greater product quality and quantity etc. The best characteristics are selected and then are bred among themselves to produce better crops. Recombinant or hybridized crops are made by incorporating desirable genes into the plant or by allowing crossing which may be intervarietal, interspecific or intergeneric.
Improvement in crop production.
Management of crop protection.
Concept: Irrigation and Cropping patterns
Irrigation is a process of supplying controlled amount of water to agricultural crops on land to grow properly, even during the period when enough rainfall does not happen. Irrigation process can be carried out by using various methods such as-
Wells are of mainly of two types. Dug wells are used to collect water from strata bearing water, and tube wells to collect water from the deeper strata by using pumps.
Canals are a broad irrigation system which can receive water from one or more reservoirs or rivers. The main canal divides into several branch canals and then distributed to several fields.
River life system is used in such areas which are closed to rivers and are directly used for drawing water.
Tanks are small reservoirs generally used to store the run-off of smaller catchment areas.
In the areas with the scarcity of water, the irrigation system mainly used is Drip Irrigation and Sprinkler irrigation.
Cropping patterns: For maximum benefit of yielding crops, prevention from pests and disease, some techniques are used to cultivation such as-
Mixed cropping is a system where more than one crop can be cultivated in the same field ,where one is the main crop and other is the subsidiary. For example, if wheat and gram are cultivated in same piece of land. It reduces the risk of total crop failure.
Intercropping is a multiple cropping system where two or more crops are simultaneously grown on the same field but alternatively. Few rows of one crop (for example soybean) are alternated with the few rows of second crops (for example maize). Both have different nutrient requirements, prevent pests and diseases spreading and result into higher yield.
Crop rotation is a cultivation system where different crops are sequentially grown in a same field of growing season. It helps to improve soil structure, balance the nutrients in the soil, control disease and pest. For example, rotation between corn, which requires heavy nitrogen, and soybean which requires less nitrogen.
Concept: Management of crop protection and Storage of grains
Growth of unwanted plants, weed (for example Xanthium, Cyprinus etc.) in the cultivated land, insect pests (which cut the leaf, stem and root, suck the sap of the cell and the bore into fruits and stem) and plant disease causing pathogens (such as bacteria, fungi and viruses transmitted through air, water and soil) lead to destruction of crops and reduced yields.
Therefore, it is important to control these by some methods like-
Pesticides including herbicides, insecticides and fungicides are sprayed on crops or are used to treat seeds and soil. As these pesticides are poisonous chemicals, excessive use of these chemicals affects both plant and animal and cause soil and water pollution.
Mechanical method is used for removal of weed. It includes seeds or khurpi.
Preventive methods are used to control weed by preparation of proper seed bed, planting crops timely, intercropping and crop rotation. These help in controlling weed. Some other methods used are , use of resistant varieties and summer ploughing.
Storage of grains
Although after the storage, the harvest loses its nutritional value. But it is important to keep harvest in a warehouse under appropriate conditions. Otherwise product would be spoilt. Loss of weight, crop quality deterioration, discoloration of harvest due to some biotic (like insects, fungi, mites etc.) and abiotic factors (like temperature and moisture) can happen if not kept properly.
Cleaning and sun drying kills majority of the pathogenic organism causing spoilage. Further fumigation is used to kill pests.
Concept: Natural resource (Air)
Air is very important for life on the earth. It is a mixture of several gases like nitrogen, oxygen, carbon-dioxide and small amounts of other gases and water vapor.
Atmosphere can control climate and helps in maintaining an average range of temperature on the earth by slowing down the sudden escape of heat (as air is a bad conductor of heat). It helps in maintaining life on earth. The temperature on Moon ranges from -190 degree Celsius to 110 degree Celsius due to lack of atmosphere although both earth and moon are about same distance from the sun.
When uneven heating of different parts of the earth takes place, then the flow of air occurs from high pressure area to low pressure area. For example, in coastal regions, during the day the land is heated faster than the water. The air on the land heats up faster and starts rising up, which creates low pressure in this region. The air over water moves to this region. This movement of the air is called Wind. This process reverses at night.
When excessive heat causes water to evaporate, then water vapor along with the hot air rise up to the point where it can expand and cool. After cooling it gets condensed and forms small droplets (water condensation is facilitated when some particles like dust act as nucleus and allow these drops to form around) . These droplets come together and grow bigger and heavier. They fall down on earth as rain at normal temperature, but at lower temperature precipitation occurs in the form of snow, sleet, or hail. Rainfall patterns also depend on the patterns of the wind.
When oxides of nitrogen and sulfur increase in the air, then the quality of air becomes bad . These compounds are produced generally by burning of the fossil fuels (examples coal, petroleum) which is not only dangerous to us for inhalation, but it dissolves in rain leading to Acid rain. Some unburnt carbon particles also remain suspended in air causing Air pollution. Pollution is also visible as Smog (Smoke and Fog) in cold weather. These pollutants are known to cause cancer, allergies, and heart disease.
Concept: Natural resource (Soil)
The upper most layer of the land in the earth, which consists of fine particles and minerals, is known as Soil. The soil is formed by gradual breaking up of large boulder and through other reactions like physical, chemical, and biological which have taken place many years ago. These reactions are carried out by factors, like:
The Sun heats the rocks unevenly (that is during day, some portion of the rock expands due to heat and at night some portion get contract due to cooling) which creates cracks and gradually breaks it into small pieces.
Water enters into these cracks and makes it wider as its water freezes at low temperature and expands. Some rocks come along with the running water and due to abrasion. Larger rocks break down into smaller remains which are further deposited down its path.
Rock erosion also occurs via strong wind which blows away the small particles like sand from one place to another place.
The soil formation is also influenced by living organisms such as lichen, mosses. These are able to grow on the rock surface which makes the surface powdery. The roots of the tree penetrate through these cracks and force the cracks to become bigger.
When naturally decaying organic living, matters are mixed with soil particles. it is called Humus. It is rich in nutrients, is fertile and retain moisture within it. The topmost layer of soil containing humus, living organisms and soil particles is called topsoil which determines the biodiversity in that particular area.
The quality of the topsoil declines due to use of artificial fertilizers and pesticides which kills soil microorganisms (responsible for recycling of nutrients in the soil) and destroys the structure of the soil leading to barren land. It is known as Soil pollution.
Concept: Natural resource (Water)
Water is a liquid matter which helps in existence of life on land. A large area of the Earth’s surface is occupied by the water. Some amount of water is also found underground and some also exist as water vapor in the atmosphere. Most of the water is found as saline water in oceans and seas. Fresh water is found as frozen icecaps at the two poles and snow-covered mountains . The ground water and the water in pond, rivers and lakes provide fresh water.
Every living organism, both unicellular and multicellular organisms on the earth, are made up of cells. For staying alive, we have to be depended on our cellular processes which are carried out by different types of cells.
It is very necessary to keep these cells moist so that they can work properly. Water is important to provide medium to the cells where all the reactions take place. It helps to transport various substances easily in the aqueous medium from one part to other part of the body.
When some undesirable substances like fertilizers, pesticides, sewages, and some toxic compound from industries mix with waterbodies. It leads to alter the normal conditions of the water. Change in optimum temperature and change in the concentration of normal dissolved oxygen (Enrichment of minerals and nutrients in water results into excessive growth of algae, causing depletion of dissolved oxygen concentration in the water. It is known as Eutrophication) is called Water pollution. It hampers the life of aquatic plants and animals and affects their breeding procedure. These toxic substances, via food chain, enter into the animal body and begin to accumulate in the body.
Concept: Biogeochemical Cycles (Carbon and Oxygen Cycle)
Carbon cycle is a cyclic pathway where carbon circulates between biotic and abiotic components. Carbon is present in various forms, like in atmosphere it is present in its gaseous form (CO2). And in diamonds & graphite it is present in elemental form. In various minerals, it is present as carbonate and hydrogen-carbonate salts.
In all living organisms, carbon acts as endoskeletons containing all biomolecules.
This cycle begins with the process of Carbon fixation, which is carried out by plants and other microorganism. They take up atmospheric CO2 gas to produce glucose molecules and O2 in the presence of sunlight and water. This process is called Photosynthesis. These glucose molecules are then taken up by other living organism to produce energy. During Respiration O2 is taken up by some aerobic living organism and CO2 is released back into the air. Other processes, like burning of fossil fuels, produces CO2 gas into the air. CO2 is one of the greenhouse gases which lead to increase in temperature on earth by preventing the escape of heat from the earth, causing global warming.
Oxygen cycle is the process of circulation of oxygen molecules in which the oxygen level in the atmosphere can be maintained. About 21% oxygen present in atmosphere in gaseous state (O2). It is also present in the earth’s crust like CO2, NO2 and oxides of most minerals. It is a very essential element of most biological molecules like carbohydrates, proteins etc. Atmospheric O2 is mostly taken by living organism (except some anaerobic microorganisms and nitrifying microorganism where O2 acts like a as toxic compound ). During respiration process, O2 converts into CO2 and which is further taken up by the green plant. Plants release O2 in the air.
Ozone Layer is composed of high concentration of ozone gas(O3), which consists of three oxygen atoms. Ozone gas is highly poisonous for all living organism. But its high concentration in the stratosphere, surrounding the earth, acts as a protective barrier by preventing damage from UV radiation. In the presence of certain compounds like CFCs (Chlorofluorocarbons), ozone molecules can be destroyed. This is responsible for creating holes in the ozone layer (seen in Antarctica).
Concept: Biogeochemical Cycles (Water and Nitrogen Cycle)
The cyclic pathway in which some compounds like water, nitrogen, carbon, oxygen etc. can circulate between biotic and abiotic forms in the biosphere is known as Biogeochemical cycle.
Water cycle is the cyclic process, in which water can circulate between seas or oceans, atmosphere, and land. In this process water evaporates from the water bodies (Evaporation), gets condensed as water vapor (Condensation) and falls as rain (Precipitation) on the land. Some water goes into the ground, where it forms reserve as ground water. Some water gest back into the sea via river. While flowing, it carries some minerals to sea or ocean ,dissolving in it from the rock’s surface and land. Water is a very important factor for all living organisms.
Nitrogen cycle is a cyclic process, where gaseous nitrogen in the atmosphere (78%) gets fixed in the form of nitrate or nitrite (Nitrogen Fixation). It occurrs by two processes- Via some nitrogen fixing microorganism that are closely associated with the roots of leguminous plants form root-nodules. And other, during lightning nitrogen molecule get converted into oxides of nitrogen which is dissolves in water to produce nitric acid and nitrous acid. This falls on land as rain which is further used by other living organism as a source of nitrogen.
Nitrogen cannot be taken directly taken by the plants. So this form of nitrogen i.e. nitrate and nitrite are taken by the plants and converted to more complex organic molecules (Proteins and nucleic acids). It then enters the food chain where every living organism gets nitrogen. Then again via some microorganisms ,which are able to convert nitrate and nitrite to elemental nitrogen, nitrogen molecules gets released in the atmosphere.
This process is called Denitrification.
Concept: Natural resources
The resources which are provided by the nature and cannot be self-made by humans are called Natural Resources. Example, air, water, soil.
It is proven that in our solar family, earth is one of the planets which has life. But for survival, it is important to interact with these natural resources like-
Lithosphere – The outer rigid surface of the earth, known as crust.
Hydrosphere -The total content of water on the earth including ground water.
Atmosphere – The layers of gases which are surrounding the earth.
And the existence of life on such parts of the earth is called Biosphere. These three factors are important to make life on this earth.
It is seen that on Earth, the atmospheric CO2 level (0.04%) is much lower than that of Venus and Mars (up to 95-97%) . This is one of the reasons to support life on earth. Although eukaryotes and many prokaryotes can use O2 for cellular activities and release CO2 in the atmosphere, but the percentage of O2 (21%) in the atmosphere is much higher than CO2 because of CO2 fixation. It is fixed by a large number of green plants, which use this CO2 and convert it into glucose in the presence of sunlight and water during Photosynthesis.
Some marine animals make their shells by using carbonates.
Concept: Animal tissue
An animal is made up of following kinds of tissues –
Epithelial tissue is the external layer of the body which is continuous with no intercellular spaces. It is raised above the basement membrane which supplies blood and nutrients for the cell metabolism inside the cell. The basic function of these tissues is to provide protection against injury. It is positioned at the skin and the alimentary lining of the body. The single layer of Epithelial tissue is called Simple epithelial tissues and multiple layers forms the Stratified Epithelial tissue. Further according to the cell shape they are classified as Squamous Epithelial as are square in shape (found in lungs and skin), might be cubical in shape so are called Cubical Epithelium(found in glands and kidneys), and might be rectangular column so are named as Columnar Epithelium tissue (found in stomach, small intestine).
The whole body is further connected by some connective tissue which separates and supports other tissues. For example, blood is a loose connective tissue where cells and are used to transport of water, nutrients , hormones and even antibodies across the body. Bones are dense connective tissue, providing frame and shape to the body. Ligaments is the constituents placed in between two bones. The fibrous tissues connect bones to muscles are called Tendons. Nose, ears etc. are made up a smooth connective tissue called Cartilage. Areolar connective tissues are loose jelly like and connects the skin to the muscles and adipose tissues are used for fat storage in our body and homeostasis of the body.
Muscular tissue consists of muscle fibers which helps to body move. Generally, there are two types of muscles have been found in an animal- Voluntary muscles works on our wish and Involuntary muscles are those which cannot be moved by ourselves (cardiac muscles in heart). Skeletal muscles are a type of voluntary muscle that helps to move the body; They are long, multi-nucleated, and cylindrical and branched and gives dark and light-colored bands under microscope so are called Striated muscles. The tissues preset in our uterus, bronchi are involuntary cells designated as Unstriated muscles and are also called Smooth muscles. The muscles of heart are called cardiac muscles and are cylindrical, branched and bears single nucleus.
Highly specialized cells called neurons make the nervous tissues. The skin consists of numerous receptors which receives the stimuli and sends them to the dendrites which is the terminal ending after the cell body. The cell body is a circular portion with cytoplasm and nucleus in it. The message from the cell body travels through the axon, then through the axon terminal to the post nerve cells. The space between the two neurons is known as Synapse. The central nervous system comprises of a Brain and a Spinal cord.
Concept: Meristematic plant tissue
Meristematic tissues are such tissues in plants that are capable of rapid division and are found on the growing parts
of plant. Since it is continuously growing it has some prominent features i.e. it has dense cytoplasm. They have
only primary cell wall. They have a large prominent nucleus has to suffer for greater round of cell divisions. And
greatly it lacks the large vacuoles but appears at the time of elongation. The cytoskeleton is absent in these types
of cells.
They are classified into following types according to their location-
Apical meristem are the tissues present in the apex, tips of a plant root or shoot. They are used in plant growth towards or away from the gravity. It is found in the shoot tips, root tip along with the root cap.
Intercalary meristem is a type of tissue present at the internodes on twigs or the base of the leaves that is it develops between regions of mature or permanent tissue. Apical and Intercalary meristem are known as Primary meristem.
Lateral meristem is a type of secondary meristematic tissue which is formed after the formation of Apical and Intercalary meristem. It increases the lateral thickness of the plant. It is also known as Cambium. The lateral thickness of the plant increases when there is extra stored food in the plant. The growth during winters gives the plant a light brown color appearance and the growth during summers gives a dark brown appearance. These dark and light brown circles is later used to predict the age of the tree.
Concept: Permanent tissue in plant
The Permanent tissues are formed by the meristematic tissues when they stop dividing. Permanent tissues are highly differentiated in their functions. They have large vacuole used in storage and even in buoyancy, with either thin or thick cell wall, for support. There are two types of Permanent tissues:
Simple permanent tissue comprises of a particular variety of cells responsible specific functions like Parenchyma. They have thin cell wall and can be of varying shape, i.e. round, elongated or even polygonal. They have intercellular spaces in between the cells. They have functions like food storage. Parenchyma are further divided according to their differentiation to work i.e.
The tissue in which photosynthesis occurs as it bears Chlorophyll is called Chlorenchyma .
The tissue having greater intercellular which provides buoyancy to the aquatic plants, example water lily is called Aerenchyma.
The tissue responsible for bending of plant parts to different organs like leaf, stem etc. is called Collenchyma .
The tissue responsible for the mechanical support of the plant composed of dead cells with thick cell wall of cellulose and lignin. Example, seed coat is called Sclerenchyma.
Epidermal cells are the external layer of plant which is responsible for the protection. They consist cells which provides waxy layer with no intercellular spaces in them which gives them mechanical strength . The epidermal cells are absent in stem and leaves have pores known stomatal opening for gaseous and water exchange. The root epidermal cell makes root hairs which increases the water absorption by increasing the surface area. After ages, these epidermal cells of the plant are further converted by thick layer of dead cork cells richen in Suberin for no gaseous exchange in them.
Complex permanent tissue comprises of varying cells working together as unit to perform a specific task. They comprise of Xylem and phloem which is produced by Procambium tissues.
Xylem is a type of conductive tissue as it transports water from the root to the different part of the plant. Vessels, tracheids, xylem fibers and Xylem parenchyma are the constituents of Xylem. The transpiration creates suction pull to pull up water from the roots of the plants. Xylem parenchyma is the only living cells present rest all are the dead cells, (Tracheids, vessels, xylem fibers lacks Protoplasm).
Phloem is used for the transport of food from the leaves to the other parts of the pants which is known as translocation which is a bidirectional movement. Sieve tubes, Phloem parenchyma, Companion cells, and Phloem fibers are the constituents of Phloem. Phloem fibers are the only dead cells rest all are living in nature.
Concept: Tissues
We all know that thousands of cells are required to make a multicellular living organism. When few organelles reside in a compartment, it is claimed to be cell. When a group of cells work together for a specific function it is called Tissue. Example, meristematic tissues in plants and connective tissue in animals. When a group of tissues work together it is known as Organ like, Stomach in animal and roots in plants. When many organs work together, they make up an organ system. Example nervous system in animals and shoot system in plants. A complete set of organ system working together gives rise to an organism. Example, humans and plants.
There are lots of differences in between plant and animal tissues. For instance-
Plant tissues are more rigid than animal tissue as plants are only required to be stationary whereas animals are mobile and require tissues, organs for movement. More ATP are required for movement in plant tissues.
Plant contains both living and dead tissues in them. Living tissues are required for metabolism and dead gives the mechanical support to the plant. Whereas animals have all living cells.
Plant tissues have specific location where the diving cell resides. The Meristematic tissues are capable of continuous division whereas the permanent tissues have lost their ability to divide. On the other hand, animal tissues do not have such specified regions for dividing or non-dividing.
Animal cells being more advanced so are greatly specialized and localized within it as compared to even in very complex plants.
Concept: Cause of disease
A particular disease can happen depending upon factors. It may primarily be caused by a particular pathogen that is responsible for a specific disease.
Other factors like low immunity, lack of nourishment, genetic difference and poor public services are also responsible.
For example, loose motion happens to a baby, which is caused by a particular pathogen or virus. This virus is able to grow in a baby’s body due to low immunity power , lack of nourishment or due to some genetic differences which makes the baby more likely to suffer. This virus may enter into the body via unclean drinking water because of poor public services.
There are two types of diseases:
Infectious disease: When a causative agent or pathogen(for example bacteria, fungi, virus, protozoa, and other parasitic organisms) is responsible for developing a particular disease, it is known as an infectious disease. Example, Helicobacter pylori is a bacteria which cause peptic ulcers. Influenza is caused by Influenza Virus. Some skin disease is caused by fungi, malaria is caused by protozoa, roundworms cause small intestine disease and so on.
As a particular pathogen causes a particular disease, so their treatment would not be the same for the different diseases. For example, antibiotics (Penicillin used to prevent the cell wall synthesis of bacteria) effect bacterial infection to prevent their cellular function but does not work for viral disease because cellular properties of viruses are different from bacteria and vice versa.
Non-infectious disease: These diseases are not caused by any infectious agent. It is totally dependent on our internal body systems. It is known as infectious diseases, like cancers occur by abnormalities of genes. Overweight and lack of exercise leads to high blood pressure and so on. These diseases are not transmissible.
Concept: Disease
Disease means something wrong happening in an individual’s body which indicates that a person is not feeling well. The person may be suffering from an abnormal situation, which may hamper his/her normal body function.
Some symptoms and signs may appear in our body. The organisms responsible for causing disease are called Pathogens.
Depending on how long a disease can last in our body, it can be divided into two types:
Acute disease:
Diseases that last for a few days, meaning it has shorter duration, is known as acute disease. For example, common cold. It has been seen that when we catch a cold, it lasts for a few days.
Chronic disease:
Those diseases that last for a longer period of time or maybe a lifetime, are known as chronic diseases. For example, elephantiasis disease.
If we compare both acute and chronic disease, we will see that chronic diseases put our health in a much worse condition than acute diseases. It affects our normal body function.
For example, sneezing and coughing do not hamper our body function much because of the short duration of this disease. But in case of tuberculosis, it severely affects our lungs, due to long duration of this disease. It leads to person losing weight, feeling tired all the time, and gradually reducing their immunity power. Reduction in immunity leads to attack by many other diseases.
Concept: Disease transmission
Infectious diseases are also called communicable diseases, because the infectious agent can spread through a variety of ways from one infected person to another uninfected person.
For example, the causative agent of the common cold can spread through air or droplets from one person to another through sneezing or coughing. As for spreading these diseases through the air, it is also known as airborne diseases.
Due to poor hygiene and lack of safe drinking water supplies, some diseases can spread through water. Some infectious agents responsible for gut disease, for example cholera, is transmitted through the fecal contamination of water.
Some diseases are transmitted through sexual act, like AIDS caused by HIV, is one type of virus transmitted by sexual contact from one person to another. This disease also spreads through blood from one person to another and is also transmitted from an infected mother to her baby via breastfeeding.
Some diseases spread through vectors (carrier organism), which may be an animal. Rabies virus responsible for rabies infection is transmitted through the saliva of infected animal, mainly dog to another animal or human. Or an insect, like female anopheles’ mosquitoes, spreads the malaria causative agent (Plasmodiumis one type of protozoa) when they suck blood from an infected person and transfer this infectious agent to another host via their next bite.
Concept: Health
Health means physical and mental condition of a person, where it can be determined if a person is having
good health. A healthy person must have good physical and mental health. Their body good should be enough to do every work, all body functions should work properly, and the person should have good immunity power to fight against diseases.
Some important factors affect our health:
Our surrounding environment affects our health. For example, if there is no one to collect garbage and dispose it to some other place. It will create health issues. Similarly, if no one wants to take responsibility to clean drains, then it would create a lot of problems. Unclean drain leads to increase in the number of mosquito population, some of which may carry the pathogen of dengue and malaria and infect us to get ill.
Our daily work out also affects our health. For example, if someone does exercise daily, it helps to boost their immunity power. Similarly, if someone dances , it stretches their body well which leads to increase in their body flexibility. If someone plays flute, they must have enough capacity in their lungs to control the notes from their flute.
Our food habits also affect our health. Fr example, if someone does not take healthy food or does not get proper nutrients, the body then cannot function properly due to lack of nutrients. Body tends to lose weight giving a feeling of tiredness all the time. Body immunity power becomes low leading to getting sick quicker than other healthy individuals.
Our behavior also affects our health. For example, happiness is the main thing to being a healthy person. If we misbehave with each other or are afraid of each other, we will not be happy and healthy. Social equality and harmony are also necessary for being healthy.
Concept: Sign and symptom
As microbes are very minute in size as compare to their host (for example human or animal), they need large enough to population to affect their host and produce signs ( which appears on the patient’s body and can easily be observed by others like rush or inflammation) and symptoms (which is only felt by the patient like back pain or exhaustion).
If very low number of causative agents (microbes) are present at specific site in one’s body, then the expression of the disease might show minor effect. But if huge number of organisms are present , the host may suffer from severe problems.
It has been seen that a particular group of microbe target specific location, tissues or organs in their host body. It is also known as tissue-specific effects, where they rapidly grow under favorable conditions. Which tissues and organs will be their target basically depends on from which route the microbes are entering into the host body. For example, if microbes enter via the nose or mouth from the air, then it highly likely to go into the lungs where they rapidly multiply and damage lung tissues. Tuberculosis microbes produce signs and symptoms like coughing, breathlessness. Long-term TB patients release blood with cough.
Other examples-if some microbes attack liver, it leads to cause jaundice. If the brain is their target organ, then it will lead to headaches, spewing & unconsciousness. Sometimes it may produce inflammation as our immune system recruits many cells in response to these microbes at a specific site, which leads to swelling and pain, and generally raising our body temperature causing fever.
There are some infections which are specific to the tissues system, as the causal organism infects specific tissues. It hampers the total body response such as HIV infection which attacks the immune system of the body, mainly lymphoid tissue, and damage it drastically. As a result, patients are unable to fight longer against germs, and simple minor cold becomes pneumonia and gradually many more diseases attack them. For this reason, HIV patient cannot survive longer, and the ultimate result is death. These are called General steaming effects caused by Opportunistic Pathogens.
Concept: Treatment and prevention
Treatment is all about curing patients of their infectious disease. There are two ways to treatments to the diseases- one is by reducing the effects of disease and the other by killing causative agents of the disease. For example, we take some medicines which can help us to reduce our body temperature or fever, reduce inflammation, and pain. As these medicines are unable to kill microbes, we will not be completely cured. Therefore, along with these medicines, we must need to take other medicines to kill those microbes.
Microbes are grouped into categories like bacteria, viruses, fungi, and protozoa on the basis of their similarities in their structural properties, cellular mechanism, and biochemical pathways. They are not similar in their mode of infection. Thus, one medicine can obviously be not applicable to different categories of pathogens. For example, antibiotic (penicillin) acts on bacteria but is not effective for other groups of microbes. Similarly, anti-viral medicines are only applicable for viruses.
Prevention means stopping something bad from happening. If we look into biological way, prevention means taking some precursors that will prevent the infectious disease from spreading.
There are two ways of Prevention:
In a general way, we can prevent microbial exposure by taking some preventive steps. Like for airborne microbes, which spread through the air. can be prevented by using face mask and staying away from overcrowding. For preventing the exposure of water-borne microbes, we should ensure that public services must supply safe drinking water where water must be treated and eliminated from microbial contamination.
Similarly, taking sufficient healthy food and doing daily exercise boost our immunity power. Personal hygiene is the most important thing.
In the specific way, we prevent a specific disease exposure by some methods. Scientist Edward Jenner found that during the epidemic of smallpox virus, some group of people (milkmaids whose cow already had cowpox) were not infected by the disease because their body already had encountered cowpox (very mild disease) virus and produced antibodies against the smallpox virus. Hence, they became immune against smallpox disease.
Immunization or vaccination (derived from the Latin word ‘Vacca’ means ‘cow’ and ‘vaccinia’ means ‘cowpox’) method, where live-attenuated or killed infectious agents are injected into the body and allow the host’s immune system to generate antibodies against such exposure of infectious agent. As a result, that particular causative agent or its closely related group of causative agents cannot cause that particular disease. Smallpox vaccines, anti-rabies vaccines, etc. are examples of such vaccines.
