CBSE Class 10 Biology Life Processes Worksheet Set 09

This printable worksheet for CBSE Class 10 Science Chapter 5, Life Processes, has 25 short questions with answers: ten fill in the blanks and fifteen very short answer questions. It revises the terms used for transpiration and digestion, the heart sounds and blood pressure, and the units of the lungs and kidneys, and it is easy to print and solve.

Fill in the Blanks

Question 1. Ninety percent of the water lost by the plants during transpiration is through the ................ of the leaf.
Answer:
Stomata.
The stomata are the tiny pores on the leaf surface, and most of the water vapour leaves through them.
In simple words: The stomata are the tiny pores on the leaf surface, and most of the water vapour leaves through them.

Teacher's Note:
1. Write the exact biological term.
2. Spell the term correctly.

Question 2. The semi-liquid mixture of partially digested food found in the stomach is called ................ .
Answer:
Chyme.
The churning of the stomach wall mixes the food with gastric juice into a semi-liquid chyme.
In simple words: The churning of the stomach wall mixes the food with gastric juice into a semi-liquid chyme.

Teacher's Note:
1. Write the exact biological term.
2. Spell the term correctly.

Question 3. The ................ prevents the entry of food into the respiratory tract.
Answer:
Epiglottis.
It is a flap that closes the opening of the trachea while we swallow.
In simple words: It is a flap that closes the opening of the trachea while we swallow.

Teacher's Note:
1. Write the exact biological term.
2. Spell the term correctly.

Question 4. Second heart sound heard as ................ is due to closure of ................ valves at the beginning of ventricular diastole.
Answer:
“Dub” (the second heart sound); semilunar valves.
The semilunar valves of the aorta and the pulmonary artery close when the ventricles relax, and this gives the “dub” sound.
In simple words: The second sound, “dub”, comes from the closing of the semilunar valves.

Teacher's Note:
1. The first sound “lub” is due to the closing of the atrioventricular valves.
2. The second sound is due to the semilunar valves.

Question 5. Kidney eliminate the excretory waste materials as their aqueous solution, called ................ .
Answer:
Urine.
Urine is a watery solution of urea and other wastes.
In simple words: Urine is a watery solution of urea and other wastes.

Teacher's Note:
1. Write the exact biological term.
2. Spell the term correctly.

Question 6. Pressure in the arteries during ventricular relaxation is called ................ pressure.
Answer:
Diastolic.
It is the lower value of the blood pressure reading, normally about 80 mm Hg.
In simple words: It is the lower value of the blood pressure reading, normally about 80 mm Hg.

Teacher's Note:
1. Write the exact biological term.
2. Spell the term correctly.

Question 7. Diffusion is insufficient to meet ................ requirement of multicellular organisms like humans.
Answer:
Oxygen.
Many body cells are far from the surface, so diffusion is too slow and lungs and blood are needed.
In simple words: Many body cells are far from the surface, so diffusion is too slow and lungs and blood are needed.

Teacher's Note:
1. Write the exact biological term.
2. Spell the term correctly.

Question 8. ................ movements take place along the gut.
Answer:
Peristaltic.
The rhythmic contraction and relaxation of the gut wall pushes the food forward.
In simple words: The rhythmic contraction and relaxation of the gut wall pushes the food forward.

Teacher's Note:
1. Write the exact biological term.
2. Spell the term correctly.

Question 9. ................ from stomach digests proteins.
Answer:
Pepsin.
Pepsin is the protein-digesting enzyme in the gastric juice.
In simple words: Pepsin is the protein-digesting enzyme in the gastric juice.

Teacher's Note:
1. Write the exact biological term.
2. Spell the term correctly.

Question 10. Starch changes blue in ................ solution.
Answer:
Iodine.
Starch gives a blue-black colour with iodine solution.
In simple words: Starch gives a blue-black colour with iodine solution.

Teacher's Note:
1. Write the exact biological term.
2. Spell the term correctly.

Very Short Answer Questions

Question 11. Define translocation.
Answer:
Translocation is the movement of food (soluble products of photosynthesis) in the form of a solution within the plant, especially through the phloem, from the leaves to the other parts.
In simple words: Translocation is the transport of food in plants.

Teacher's Note:
1. Name the phloem.
2. It is not the movement of water.

Question 12. What is glomerulus?
Answer:
The glomerulus is a bunch of fine blood capillaries present in the cup-shaped Bowman’s capsule of a nephron, where the blood is filtered (ultrafiltration).
In simple words: The glomerulus is the filtering knot of capillaries in the nephron.

Teacher's Note:
1. Mention the Bowman’s capsule.
2. Filtration takes place here.

Question 13. What is osmoregulation?
Answer:
Osmoregulation is the maintenance of a fixed osmotic concentration of the body fluids by controlling the amount of water and salts in the body.
In simple words: Osmoregulation keeps the water and salt balance of the body steady.

Teacher's Note:
1. Kidneys help in osmoregulation.
2. Include both water and salts.

Question 14. Define lenticels.
Answer:
Lenticels are small aerating pores in the bark (cork) of woody stems that allow the exchange of gases between the atmosphere and the inner tissues of the stem.
In simple words: Lenticels are the breathing pores of woody stems.

Teacher's Note:
1. Stomata are on leaves; lenticels are on stems.
2. They allow gas exchange.

Question 15. What is holozoic nutrition?
Answer:
Holozoic nutrition is the mode of nutrition in which an organism takes in solid or liquid organic food (ingestion), digests it, absorbs and assimilates it, and egests the undigested part. Examples are amoeba and human beings.
In simple words: Holozoic nutrition means taking in food and digesting it inside the body.

Teacher's Note:
1. List the steps: ingestion, digestion, absorption, assimilation and egestion.
2. Give an example.

Question 16. What is the life span of RBCs (Red Blood Cells)?
Answer:
The life span of red blood cells is about 120 days.
In simple words: An RBC lives for about four months.

Teacher's Note:
1. Remember the number 120.
2. Old RBCs are broken down in the spleen and liver.

Question 17. What is the common passage for food and air?
Answer:
The pharynx is the common passage for food and air.
In simple words: The pharynx is shared by the food path and the air path.

Teacher's Note:
1. The epiglottis decides where the food goes.
2. Food goes on to the oesophagus.

Question 18. Name the part of an alimentary canal where digestion does not occur.
Answer:
Digestion does not occur in the oesophagus (which only passes the food on by peristalsis) and in the large intestine (where water is absorbed from the undigested food).
In simple words: No digestion happens in the oesophagus or the large intestine.

Teacher's Note:
1. Both of these parts only move or absorb.
2. Digestion is completed in the small intestine.

Question 19. Which vitamins are stored in liver?
Answer:
The liver stores the vitamins A, D, E, K and B₁₂.
In simple words: The liver is a store of several vitamins.

Teacher's Note:
1. Name at least vitamins A and D.
2. The liver also stores iron and glycogen.

Question 20. What is the respiratory pigment that takes part in transportation of oxygen in humans?
Answer:
The respiratory pigment is haemoglobin, present in the red blood cells.
In simple words: Haemoglobin carries oxygen in our blood.

Teacher's Note:
1. It contains iron.
2. It gives blood its red colour.

Question 21. What is the primary function of red blood cells?
Answer:
The primary function of red blood cells is to carry oxygen from the lungs to the body cells, and to bring some carbon dioxide back to the lungs.
In simple words: RBCs are the oxygen carriers of the blood.

Teacher's Note:
1. Name haemoglobin as the pigment.
2. Oxygen transport is the main job.

Question 22. Name the artery that has deoxygenated blood and vein that has oxygenated blood.
Answer:
The pulmonary artery carries deoxygenated blood (from the heart to the lungs) and the pulmonary vein carries oxygenated blood (from the lungs to the heart).
In simple words: The pulmonary vessels are the exceptions to the usual rule.

Teacher's Note:
1. Arteries usually carry oxygenated blood and veins deoxygenated.
2. The pulmonary vessels are the exceptions.

Question 23. State two functions of intestinal villi.
Answer:
(i) They increase the surface area of the inner wall of the small intestine.
(ii) They absorb the digested food into the blood.
In simple words: Villi make a bigger surface so that more food can be absorbed.

Teacher's Note:
1. Write two separate points.
2. The villi have a rich blood supply.

Question 24. Name the two stages of photosynthesis.
Answer:
The two stages are the light reaction (which needs light) and the dark reaction (which does not need light directly).
In simple words: Photosynthesis has a light stage and a dark stage.

Teacher's Note:
1. Light reaction: water is split and oxygen released.
2. Dark reaction: carbon dioxide is reduced to glucose.

Question 25. Mention the respiratory unit of lungs and excretory unit of kidneys.
Answer:
The respiratory unit of the lungs is the alveolus (plural alveoli), and the excretory unit of the kidneys is the nephron.
In simple words: Alveoli are the units of the lungs; nephrons are the units of the kidneys.

Teacher's Note:
1. Alveolus is the singular word.
2. Do not confuse the two units.