"AKC SCIENCE CLASSES"
CLASS 10 TH (CBSE AND MP BOARD)
CHAPTER 06
LIFE PROCESSES
BASIC CONCEPTS (PART 01)
(1) Some short of movement, either visible like growth-related or other movements or invisible movements such as movements of molecules in the body, are a characteristics of life.
(2) Living organisms are well organized structure. They may have cell and cells in tissue form. Cells have smaller components in them. Due to the effect of the environment overtime, there is continuous breakdown. So, living organisms keep repairing and maintaining their structures. Because all these structures are made up of molecules they are required to move molecules around all the time.
(3) Life on earth depends on carbon based molecules. So, organisms obtain carbon molecules from the environment either in the form of CO2 as in green plants or in the form of food.
(4) Diffusion process is insufficient to meet the oxygen requirement of multicellular organisms.
(5) Nutrition is a process of intake as well as utilization of nutrients by an organism.
(6) Nutrient is a substance which an organism obtains from its surroundings and uses it either as an energy source or for biosynthesis of body constituents.
(7) There are two major types of nutrients known as Autotrophic and Heterotrophic.
(8) Green plants are autotrophs i.e., they are able to synthesis organic nutrients with the help of atmospheric carbon dioxide, water and solar energy. This process is called a photosynthesis. Green plants are able to synthesis all the organic molecules associated with life through photosynthesis.
(9) Heterotrophic plants and animals adopt various mode of nutrition. All heterotrophic organisms like non-green plants and animals are directly or indirectly dependent on green plants for nutrition.
(10) The food in by the animals is in the complex form. This must be broken down into simpler form hence there is an elaborate digestive system in animals that helps in the digestion of food which is aided by various enzymes.
(11) During photosynthesis the following events occur :-
- Absorption of light energy by chlorophyll.
- Conversion of light energy to chemical energy. Also splitting of water molecules into hydrogen and oxygen.
- Reduction of carbon dioxide to carbohydrates.
(13) Herbivores (plant eaters) have larger small intestine to digest cellulose whereas meat eaters (carnivores like tiger) have shorter small intestine.
(14) Alimentary canal :- Human digestive system consists of alimentary canal and its associated glands. Alimentary canal extends from mouths to anus.
(15) Assimilation :- The simple molecules of nutrients are absorbed and carried away to different cells of body for utilization. The nutrients are utilized for
- building up of bodies / body tissues or replacement purposes (e.g., worn out cells) and
- obtaining energy.
Fats are digested and absorbed as fatty acids and glycerol. They are again made into various types of fats and lipids. The excess of fats are stored in adipose tissues.
Proteins are absorbed as amino acids. Each cell synthesis its required protein. Excess of amino acids are broken down each day. They are not stored but removed from the body as urea (waste products).
(16) Aerobic respiration is the process in which glucose is completely broken down to CO2 AND H20 in the presence of oxygen.
(17) Anaerobic respiration is the process in which food is (glucose) broken down incompletely to ethyl alcohol or lactic acid in the absence of oxygen.
(18) Plant roots take up oxygen present in between the soil particles by the process of diffusion.
(19) ATP, Adenosine triphosphate, is known as the energy currency for most of the cellular processes. It is formed from ADP (Adenosine diphosphate) and inorganic phosphate in the availability of energy approximately 30.5 KJ/mol.
(20) Alvoli are sac like structures found in the human lungs at the end of each smaller air tube. Alvoli are richly supplied with blood capillaries for exchange of gases between blood and air breathed in.
(21) Transportation of materials in living organisms :- The transportation of materials in the living bodies of plants and animals is a life process. In this process a substance absorbed or synthesized by one part of the body is moved to other parts of the body.
(22) Circulatory system :- The organ system which is responsible for transportation of materials within the body of an animal is called a system. For example, blood circulatory system in man.
(23) Transpiration :- The loss of water in vapour from mainly from the leaves (or other parts of plants) is called transpiration.
(24) Sieve tubes :- These are the main elements of phloem which help in transportation of prepared food.
(25) Translocation :- Transport of food from leaves to other parts of the plant is called translocation.
(26) Heart :- The human heart is four chambered namely right atrium, left atrium, right ventricle and left ventricle. Heart is made up of special muscles called cardiac muscles. Heart receives deoxygenated blood from body tissues/organs through veins. It pumps deoxygenated blood to lungs for oxygenation. On receiving oxygenated blood, the heart pumps blood to different body parts. The heart beats all the time throughout one's life.
(28) Artery :- The thick walled vessels which carry blood from heart to different parts of body are called arteries.
(29) Veins :- The thin walled vessels which carry blood from different parts of the body to the heart are called veins.
(30) Capillaries :- Blood vessels occurring at the terminals of artery and veins.
(31) Plasma :- It is a colorless fluid of blood and contains water and proteins.
(32) Red blood corpuscles :- The cells in blood which contains a red pigment called haemoglobin. These are circular in shape and RBCs have no nuclei in human blood.
(33) Whiter blood corpuscles :- The cell in the blood which protects body from infections. They are nucleiated.
(34) Blood platelets :- The fragments of the the cells. They do not have nuclei. They help in clotting of blood.
(35) Immunity :- The power of fightening against infections is called immunity.
(36) The force that blood exerts against the wall of a blood vessel is called blood pressure. Blood pressure is measured with an instrument called sphygmomanometer.
(37) Heart-beat :- The rhythmic contraction and relaxation of the heart is called heart-beat.
(38) Double circulation :- The blood flows twice through the heart in one cycle it is called double circulation.
(39) Lymph :- It is a light yellow fluid containing lymphocyte cells which fight against infections.
(40) Excretion :- The removal of the excess of toxic wastes from the body is called excretion. Kidneys are the main excretory organs in human beings.
(41) Excretion in amoeba :- Removal of wastes and excess water in amoeba takes place by simple diffusion through the contractile vacuoles.
(42) Excretion in earthworm :- The excretion in earthworm takes place through an excretory organ called Nephridia.
(43) Nephrons :- Each kidney is made up of various excretory units called nephrons. Each nephron has a cup shaped upper end called Bowman's capsule containing a bundle capillaries called capillaries called Glomerulus. Bowman's capsule leads into tubular structure.
(44) Osmoregulation :- The process of regulating water contents and ion concentration in the body is called osmoregulation.
(45) Dialysis :- The procedure used in artificial kidney in place of normal is called dialysis.
(46) Plants stores many waste products in vacuoles. Some waste products are removed along with the leave that fall off. Some waste products are stored in the dead tissues (like vessels) of old xylem. Plants also excrete some waste in the soil.
