Ncert class 10 - science - chapter 6 -l ife processes

This PPT contains the important points of the lesson Life Processes - Chapter 6 - Class 10 Science.

1. Life Processes Transportation & Excretion Class X- Science-Chapter 6 Biology by Eswari Kumaravel M.Sc., M.Phil., B.Ed.

2. Transportation in Humans

3. Blood Fluid connective Tissue that circulates in a closed system of blood vessels. Components of Blood : Plasma Blood Corpuscles (RBC & WBC) Platelets Plasma: Straw coloured liquid with 92% water It transports food, CO 2 and nitrogenous waste

4. Blood Red blood corpuscles: Iron containing respiratory pigment – Haemoglobin It transports Oxygen. White blood corpuscles: Ingest and destroy bacteria Prevents the spread of infection. Platelets: Help in clotting of the blood

5. Functions of Blood Transport of Respiratory gases Oxygen from Lungs to Cells ( Haemoglobin ) Carbon dioxide from tissues to lungs (Plasma) Transport of nutrients Absorption in small intestine (Digested food) Transport of Waste Products Urea, Uric acid to Kidney Defence against infection WBC digests and engulfs bacteria and produces antibodies.

6. Human Heart Structure Muscular Organ – made of cardiac muscles Located in the middle of the chest and tilts towards the left. It has 4 chambers . 2 Upper Chambers ( Atria ) – Thin walled 2 Lower chambers ( Ventricles ) – Thick walled

7. Human Heart Structure Right and left side are separated by Septum . Aperture between Atria and Ventricles is controlled by valves . Valves prevent the back flow of blood. https://www.youtube.com/watch?v=46u2ON6d4mg

8. Working of Heart Cardiac cycle consists of one heart beat. i.e. One cycle of contraction and relaxation of cardiac muscles.

9. Heart in other animals In birds and mammals , oxygenated blood is separated from deoxygenated blood. Efficient supply of Oxygen for high energy and to maintain their body Temperature In Amphibians , 3 chambered heart which is not separated completely. Body Temperature varies with environment. In Fish , Only 2 chambered heart. Oxygenated in the gills and pumps in the heart only once.

10. Working of Heart Double Circulation Blood passes through the heart twice in one complete cycle of the body. Hence it is called as Double circulation Pacemaker Small mass of muscle cells in right atrium walls near the opening of Venacava . Sino Atrial Node (SA Node) Initiates and Maintains heart beat. In case of its failure, electronic device “Pacemaker” is implanted. ECG (Electrocardiograph) Graphical representation of the electrical changes during heart beat. Records rate and rhythm of heart with the help of electrodes

11. Types of Blood Vessels: Arteries vs. Veins Arteries Veins Thick walled Thin walled Deep seated Superficial Carry blood away from heart Carry blood to the heart Carry Oxygenated blood except Pulmonary Artery Carry deoxygenated blood except Pulmonary Vein No valves are present Valves are preent

12. Capillaries Arteries divide repeatedly to form very thin walled vessels called capillaries (one cell thick). Exchange of materials between blood and cells takes place across the wall. Capillaries then join to form veins.

13. Quiz Time What is transportation of materials? It is the process of movement of oxygen, CO 2 , waste substances and secretion of glands from regions of availability to the regions of storage or excretory organs. Give reasons for: Oxygenated and deoxygenated bloods are separate in the heart of mammals. This allows a highly efficient supply of oxygen, and meet their high energy needs (as they are warm–blooded animals) which helps to maintain body temperature. (ii) Ventricles are thick walled . Because they have to pump blood throughout the body or into various organs Why Ventricles are having thick wall ? To pump blood into various organs, Ventricles have thicker muscular walls than the atrias

14. Quiz Time Important components of blood and their functions: (i) Plasma It helps in the transport of nutrients, salt waste materials, Hormones and antibodies. (ii) Red Blood Corpuscles It helps in the transportation of oxygen and carbon dioxide. (iii) White Blood Corpuscles It helps in protection by destroying disease causing micro organisms. ( iv) Blood Platelets It helps in the synthesis of thromboplastin for clotting of blood.

15. Quiz Time Arteries wall is thicker than vein. Why? To withstand high pressure blood comes from ventricles, the arteries have thick elastic walls. What is the use of 4 chambered heart in Mammals and birds? 4 chambered heart prevents mixing of oxygenated and deoxygenated blood. Such separation allows a highly efficient supply of oxygen to the body. This is useful in animals that have high energy needs, such as birds and mammals , which constantly use energy to maintain their body temperature. Importance of platelets during injury? To avoid leakage on the place of injury, blood has platelet cells which circulate around the body and plug these leaks by helping to clot the blood at these points of injury.

16. Quiz Time Functions of Lymph? Lymph carries digested and absorbed fat from intestine and drains excess fluid from extra cellular space back into the blood. Difference between Blood and Lymph? Blood – red in color and contains more protein Lymph – colourless and contains less protein List three differences between arteries and veins. Arteries Veins Carry Oxygen rich blood away from heart except pulmonary artery Carry deoxygenated blood towards the heart except pulmonary vein Mostly deeply situated in the body Superficial and deep in location Have thick, elastic walls Thin walled

17. Quiz Time Match the following What is Blood Pressure? The force that blood exerts against the wall of elastic blood vessels is called blood pressure. Blood pressure is measured with an instrument called sphygmomano meter. A B Pulmonary Artery Transport deoxygenated blood from other parts of the body to right auricle Pulmonary Vein Transport oxygenated blood from left ventricle to different parts of the body Aorta Transport blood to lungs to get oxygen from right ventricle Veins Transport oxygenated blood from lungs to left auricle

18. Transport of Material in Plants

19. Transport of Material in Plants Plants have specialized conducting tissues Xylem : to transport water and dissolved minerals upwards from the roots to different parts of the plants. Xylem is made up of four kind of cells namely Tracheids , Vessels, Xylem fibres and Xylem Parenchyma Phloem : to distribute food prepared by leaves to different parts of the plants.

20. Specialized Conducting Tissues Xylem Phloem Transport Water and mineral salts from roots to different parts of the plant Translocate food in aqueous form from leaves to different parts Transport is passive Transport is active Vessels and Tracheids are dead cells Sieve tube and companion cells are living ccells Xylem Tissue has four type of cells namely Vessels, Tracheids , Xylem Fibres , Xylem Parenchyma

21. Tracheids Vs Vessels Tracheids Vessels Elongated, thin cells with tapering ends Elongated tube like structures placed end to end Thick liquified walls with pits along the thick walls Liquified walls with pits Water travels through pits from one tracheid to another Open end walls . So water moves from one vessel to another.

22. Transport of water and dissolved minerals

23. Transport of water and dissolved minerals Transpiration: Evaporation of water from the surface of the leaves through stomata Roots take up water again due to transpiration pull

24. Transport of Food and Other substances Photosynthesis: Leaves produce food with the help of light in a process called Photosynthesis Translocation : Food produced in leaves is transported to various parts of the plant in a process called Translocation.

25. Quiz Time What is Translocation? The process of transportation of food from leaves to other parts of plant body is called translocation. It occurs in the part of vascular tissue known as Phloem. What is Transpiration? The process of loss of water from plant body in the form of water vapour especially through stomata is called transpiration. Differentiate between Xylem and Phloem. Xylem Phloem Conducts water Conducts food Unidirectional transport – only upward Multidirectional transport – both upward and downward Transpiration doesn’t require energy Translocation in the phloem is achieved by utilizing energy Contains 3 types of dead cells Contains only one dead cell

26. Excretion in Humans

27. Excretion Process of removal of harmful metabolic waste from the body of an organism. Organs involved: A pair of kidneys (abdominal cavity) A pair of Ureter Urinary bladder Urethra Metabolic Waste Urea, Uric acid, CO 2 and water

28. Nephrons There are millions of long coiled tubules called Nephrons in Kidney. They are the functional unit of Kidney.

29. Nephrons There are millions of long coiled tubules called Nephrons in Kidney. They are the functional unit of Kidney. Bowman’s Capsule (One end) (Hollow shaped) Tubular Structures Have bundle of blood capillaries. ( Glomerulus ). One end attached to renal artery Collecting duct

30. Excretory Process Filtration Renal Artery (brings blood and waste products Glomerulus (Filtration) Bowman’s Capsule (Glucose, amino acids, Salts, Urea, Water etc.)

31. Excretory Proces s Reabsorption Reabsorption is the process by which filtrate moves to the tubules where water, glucose, amino acids are absorbed by the surrounding capillaries. These will be later returned to blood. Urine Formation Waste materials (not reabsorbed) Urine (Collecting duct) Water Urinary Bladder Urethra Nitrogenous Wastes

32. Kidney Functions and Failure Osmoregulation is the control of water content and mineral salts of the body. Kidney is responsible for Osmoregulation in our body. Kidney Failure : Can happen through infection, injury and restricted blood flow. Can be treated through transplant or Dialysis. Dialysis is done through artificial Kidneys.

33. Principle of Dialysis Dialysis Machine Long cellulose Tubes Coiled in a tank containing dialyzing solution Artery blood flows into Machine Cellulose tubes filters and absorbs the waste Solution contains water, glucose, salts with concentration similar to that of blood Pumped into vein of arm

34. Quiz Time Which is the structural and functional unit of Human Kidney? Nephrons. What is excretion? The process of removal of nitrogenous waste substances produced during metabolic activities of the body is called excretion . What are excretory substances excreted from Human Kidney? Urea Which process helps in the removal of waste substances from blood while kidney failure? Dialysis

35. Quiz Time What is osmoregulation? Osmoregulation is the maintenance of optimum concentration of water and salts in the body fluids. What causes the liquid part of blood to filter out from glomerulus into the renal tubule? High pressure causes the liquid part of blood to filter out from glomerulus into the renal tubule.

36. Excretion in Plants

37. Excretion in Plants Plant wastes are stored in Cellular Vacuoles . Gaseous wastes such as CO 2 (from respiration), O 2 (from photosynthesis) are removed through stomata pores . Liquid wastes such as water are removed through transpiration in stomata. Other wastes Some wastes are stored in dead cells of the leaves which are discarded through shedding of leaves . Resins, gums, oils are stored in old xylem. Few other waste materials are removed from nodes into the soil.

38. Quiz Time What are methods used by Plants to get rid of excretory products? Get rid of excess water by transpiration. Waste products may be stored in leaves that fall off. Other waste products are stored as resins and gums. Excrete some waste substances into soil around them.

39. Activities

40. Activity 6.1 Aim To prove that chlorophyll is essential for photosynthesis. Materials Required: Potted Plant with Variegated Leaves Sheet of Paper Beaker Alcohol Water Bath Bunsen Burner Diluted Solution of Iodine

41. Activity 6.1 Keep it in Dark room for 3 days Potted Plant with Variegated Leaves All Starch is used up

42. Activity 6.1 Observation: The colour of the iodine on leaf at dark spots changes to blue-black and not anywhere else. Conclusion: Chlorophyll is necessary for photosynthesis to prepare starch

43. Activity 6.2 Aim To prove that carbon dioxide is essential for photosynthesis. Materials Required: Two potted plants Two bell shaped glass jars Watch Glass Potassium Hydroxide (KOH) Vaseline Glass plates.

44. Activity 6.2 Keep them in Dark room for 3 days Two Potted Plants All Starch is used up Starch Test

45. Activity 6.2 Starch Test: Refer to Activity 6.1 Observation: Leaf of the plant with KOH will not turn blue-black as KOH absorbs carbon dioxide required for photosynthesis. Leaf of the plant without KOH will have carbon dioxide for photosynthesis and hence the leaf will have starch resulting in blue-black colour . Conclusion: Carbon dioxide is essential for starch formation.

46. Activity 6.3 Action of Saliva on Starch Take two test tubes having starch solution. Add Saliva to one of the test tubes. Add iodine solution to both of them.

47. Activity 6.3 Observation: Test tube without Saliva turns blue-black . Test Tube with saliva doesn’t turn blue black. But changes into reddish brown colour . Conclusion. Saliva digests starch into simple sugar and hence Iodine doesn’t change it into blue-black.

48. Activity 6.4 Presence of CO 2 in exhaled air Test Tube A: Use a syringe to pass air through fresh limewater. Test tube B: Take freshly prepared lime water and blow air through this lime water.

49. Activity 6.4 Observation: Limewater turns milky after some time in Test Tube A . Limewater turns milky in Test Tube B. CO 2 + Ca (OH) 2 CaCO 3 ↓ + H 2 O Conclusion: As air contains less percentage of CO 2 , it takes some time for the lime water to turn milky. Exhaled air contains more CO 2 than in air and turns lime water milky sooner

50. Activity 6.5 Product of Fermentation is Carbon dioxide Fruit Juice or Sugar Solution in Test Tube + Yeast Fit the test tube with one holed cork Fit the cork with Bent Glass tube Glass tube à Test tube with lime water Lime Water turns Milky

51. Activity 6.5 Observation: Lime water turns milky. Conclusion: O ne of the products of Fermentation is Carbon di oxide.

52. Activity 6.6 Rate of Breathing Fish in Aquarium opens and close their mouth and the gill-slits behind their eyes also open and close. Count the number of times fish opens and closes its mouth in a minute. Compare with your breathing rate Observation: Rate of Breathing in a fish is much faster than human beings.

53. Activity 6.7 Range of Haemoglobin Visit a health centre in your locality. Find out the normal range of haemoglobin count in children, men and women. Observation: Haemoglobin in men > in women > in children

54. Activity 6.8 Process of Transpiration Experiment Take two pots Need to have a plant. Place a stick with the same height Cover the soil with Plastic sheet Cover the soil with Plastic sheet To prevent Evaporation Cover the Leaf with Plastic bag Cover the stick with plastic bag Leave both the pots in Sunlight Pot 1 Pot 2

55. Activity 6.8 Observation Pot with plant – Small drops of water on the plastic bag covering the leaf. Pot with Stick – no water droplets are seen on plastic bag. Conclusion Living plants absorb water from the soil and water gets transported to the leaves. Loss of water takes place through leaves by the process of Transpiration.

56. Thank you