CBSE Class 10 Biology Life Processes Worksheet Set B

Multiple Choice Questions (MCQs)

Question. Which of the following has the longest small intestine ?
(a) carnivore
(b) omnivore
(c) herbivore
(d) autotroph
Answer : C

Question. The process of obtaining food by Amoeba is known as :
(a) dialysis
(b) cytokinesis
(c) phagocytosis
(d) amoebiasis
Answer : C

Question. The organism having parasitic mode of nutrition is :
(a) Penicillium
(b) Plasmodium
(c) Paramecium
(d) Parrot
Answer : B

Question. One of the following organisms has a saprophytic mode of nutrition. This organism is :
(a) mushroom
(b) malarial parasite
(c) leech
(d) lice
Answer : A

Question. The length of small intestine in a human adult is about :
(a) 4.5 m
(b) 1.5 m
(c) 3.5 m
(d) 6.5 m
Answer : D

Question. The process of digestion of food in humans begins in :
(a) stomach
(b) food pipe
(c) mouth
(d) small intestine
Answer : C

Question. The process of digestion in humans is completed in :
(a) oesophagus
(b) small intestine
(c) stomach
(d) large intestine
Answer : B

Question. In human digestive system, bile is secreted by :
(a) pancreas
(b) liver
(c) kidneys
(d) stomach
Answer : B

Question. Two of the following organisms have a holozoic mode of nutrition. These organisms are :
(a) Paramecium and Plasmodium
(b) Plasmodium and Parakeet
(c) Parakeet and Paramecium
(d) Paramecium and Parasite
Answer : C

Question. The autotrophic mode of nutrition requires :
(a) carbon dioxide and water
(b) chlorophyll
(c) sunlight
(d) all of the above
Answer : D

Question. The correct order of steps occurring in nutrition in animals is :
(a) Ingestion → Absorption → Digestion → Assimilation → Egestion
(b) Ingestion → Digestion → Assimilation → Absorption → Egestion
(c) Ingestion → Digestion → Absorption → Assimilation → Egestion
(d) Ingestion → Assimilation → Digestion → Absorption → Egestion
Answer : C

Question. In human digestive system, the enzymes pepsin and trypsin are secreted respectively by :
(a) pancreas and liver
(b) stomach and salivary glands
(c) pancreas and gall bladder
(d) stomach and pancreas
Answer : D

Question. When carrying out the starch test on a leaf, why is it important to boil the leaf in alcohol ?
(a) to dissolve the waxy cuticle
(b) to make the cells more permeable to iodine solution
(c) to remove the chlorophyll
(d) to stop chemical reactions in the cells.
Answer : C

Question. Pancreatic juice contains enzymes which digest :
(a) proteins and carbohydrates only
(b) proteins and fats only
(c) fats and carbohydrates only
(d) proteins, fats and carbohydrates
Answer : D

Question. Which of the following is the correct statement regarding bile ?
(a) secreted by bile duct and stored in liver
(b) secreted by gall bladder and stored in liver
(c) secreted by liver and stored in bile duct
(d) secreted by liver and stored in gall bladder
Answer : D

Cct Questions:

IV. Blood transport food, Oxygen and waste materials in our bodies. It consists of plasma as a fluid medium. A pumping organ [heart] is required to push the blood around the body. The blood flow through the chambers of heart in a specific manner and direction.
While flowing throughout the body, blood exert a pressure against the wall or a vessel.

Question. Oxygenated blood from lungs enters left atrium through
A. Vena cava
B. Pulmonary artery
C. Pulmonary vein
D. Aorta
Answer : C

Question. The rate of blood flow in the capillaries is very low because capillaries are
A. Very narrow and have high resistance
B. Much wide and have low resistance
C. Very narrow and have low resistance
D. Much wide and have high resistance
Answer : C

Question. Which of the following statements are true about human heart?
A. It is a hollow muscular organ
B. It is four chambered having three auricles and one ventricle.
C. It has different chambers to prevent O2 rich blood from mixing with the blood containing CO₂
D. Both A & C
Answer : D

Question. Study the table below and select the row that has correct information.
A. Blood = Plasma + RBC + WBC + Platelets
B. Plasma = Blood – RBC
C. Lymph = Plasma + RBC
D. Serum = Plasma + RBC + WBC
Answer : A

Assertion Reason Type Questions

Following questions consists of two statements – Assertion (A) and Reason (R). Answer these questions selecting the appropriate option given below:
A. Both assertion and reason are true, and reason is the correct explanation of assertion.
B. Both assertion and reason are true, but reason is not the correct explanation of assertion.
C. Assertion is true but reason is false.
D. Assertion is false and reason is true.

Question. Assertion: At high altitudes the pressure of oxygen falls, inside lungs.
Reason: Oxygen is absorbed very quickly from alveoli to increase breathing rate.
Answer : A

Question. Assertion: The Alveoli provide a surface where exchange of gases takes place.
Reason: The Alveolar blood vessels transport oxygenated blood to all the cells of the body.
Answer : A

Question. Assertion: Mammals and birds have four chambered hearts.
Reason: Mammals and birds are warm blooded.
Answer : A

Question. Assertion: Bread tastes sweet on chewing.
Reason: Salivary amylase converts starch into sugar.
Answer : A

Question. Assertion: Arteries always carry oxygenated blood.
Reason: Arteries transport blood from the heart to different parts of the body.
Answer : A

Question. Assertion: Anaerobic respiration requires more energy as compared to aerobic respiration.
Reason: Mitochondria is the power house of the cell
Answer : D

Very Short Answer Type Questions

Question. Which is the basic requirement of living organisms for obtaining energy ?
Answer :  Food

Question. Which of the following type of energy is used by living organisms to perform vital life processes ?Kinetic energy, Chemical energy, Potential energy, Nuclear energy
Answer :  Chemical energy

Question. The leaves of a plant first prepare food A by photosynthesis. Food A then gets converted into food B. What are A and B ?
Answer :  A is glucose ; B is starch

Question. What is the name of those cells in the leaf of a plant which control the opening and closing of stomata?
Answer :  Guard cells

Question. Name an animal whose process of obtaining food is called phagocytosis.
Answer :  Amoeba

Question. Which of the following is an autotroph ? Green plant or Man
Answer :  Green plant

Question. (a) Name a gas used in photosynthesis.
(b) Name a gas produced in photosynthesis.
Answer :  (a) Carbon dioxide (b) Oxygen

Question. Fill in the following blanks with suitable words :
(a) All green plants are..................
(b) All non-green plants and animals are ..............
(c) Heterotrophs depend on.............and other................... for food.
(d) Green plants use.............,................and...............to make food.
(e) Iodine turns blue-black on reacting with........................
Answer :  (a) autotrophs (b) heterotrophs
(c) plants ; animals (d) carbon dioxide, water, sunlight (e) starch

Short Answer Type Questions

Question. (a) What is chlorophyll ? What part does chlorophyll play in photosynthesis ?
(b) (i) Which simple food is prepared first in the process of photosynthesis ?
(ii) Name the food which gets stored in plant leaves.
Answer :  (b) (i) Glucose (ii) Starch

Question. Match the organisms given in column I with the processes given in column II :
       Column I        Column II
(i) Leech            (a) Holozoic nutrition
(ii) Amoeba        (b) Autotrophic nutrition
(iii) Mushroom    (c) Parasitic nutrition
(iv) Green plant  (d) Saprophytic nutrition
Answer :  (i) c (ii) a (iii) d (iv) b

Question. Name the following :
(a) The process in plants which converts light energy into chemical energy.
(b) Organisms that cannot prepare their own food.
(c) Organisms that can prepare their own food.
(d) The cell organelle where photosynthesis occurs.
(e) The cells which surround a stomatal pore.
(f) An enzyme secreted by gastric glands in stomach which acts on proteins.
Answer :  (a) Photosynthesis
(b) Heterotrophs (c) Autotrophs (d) Chloroplast (e) Guard cells (f) Pepsin

Question. Match the terms in column I with those in column II :
     Column I      Column II
(i) Trypsin         (a) Liver
(ii) Amylase      (b) Gastric glands
(iii) Bile            (c) Pancreas
(iv) Pepsin        (d) Saliva
Answer :  (i) c (ii) d (iii) a (iv) b

Question. (a) What is common for Cuscuta, ticks and leeches ?
(b) Name the substances on which the following enzymes act in the human digestive system :
(i) Trypsin (ii) Amylase (iii) Pepsin (iv) Lipase
(c) Why does absorption of digested food occur mainly in the small intestine ?
Answer :  (a) Parasitic mode of nutrition (b) (i) Proteins (ii) Starch (iii) Proteins (iv) Fats (c) Due to the presence of a large number of villi

Question. (a) How do guard cells regulate opening and closing of stomatal pores ?
(b) Two similar green plants are kept separately in oxygen free containers, one in dark and the other in continuous light. Which one will live longer ? Give reasons.
Answer :  (b) Plant kept in continuous light will live longer because it will be able to produce oxygen required for its respiration by the process of photosynthesis

Question. (a) What would happen if all the green plants disappear from the earth ?
(b) If a plant is releasing carbon dioxide and taking in oxygen during the day, does it mean that there is no
photosynthesis occurring ? Justify your answer.
Answer :  (a) Green plants are the
source of food for all the organisms. If all the green plants disappear from the earth, then all the organisms (herbivores, carnivores and omnivores) will die due to starvation
(b) When photosynthesis occurs during the day, the carbon dioxide released by plants by respiration is all used up and not released. Similarly, some of the oxygen produced during photosynthesis is used up in respiration. Since the plant here is releasing carbon dioxide and taking in oxygen even during the day, it means that no photosynthesis is taking place

Question. (a) Leaves of a healthy potted plant were coated with vaseline. Will this plant remain healthy for long ? Give reason for your answer.
(b) What will happen to the rate of photosynthesis in a plant under the following circumstances ?
(i) cloudy day in morning but bright sunshine in the afternoon
(ii) no rainfall in the area for a considerable time.
(iii) gathering of dust on the leaves
Answer : (a) This plant will not remain healthy for long because vaseline coating closes the stomatal pores on the leaves due to which
(i) plant will not get oxygen for respiration
(ii) plant will not get carbon dioxide for photosynthesis, and
(iii) plant will not get water (and minerals) due to stoppage of transpiration
(b) (i) Decreases in morning but increases in the afternoon (ii) Decreases (iii) Decreases

Important Questions for NCERT Class 10 Science Life Processes

Question. What are the differences between autotrophic nutrition and heterotrophic nutrition?
Answer : 

3) Urinary bladder – Ureter pours its contents into a muscular sac called the urinary bladder.

4) Urethra – Urine flows from bladder to the outside through the urethra.

 

Question. Saliva contains an enzyme called:
(a)Trypsin
(b) Ptyalin
(c) Amylase
(d) Pepsin
Answer : Correct option(c)

 

Question. (i) Draw a well labeled diagram of human digestive system

(ii) Describe the role of following in digestion.

a) Bile

b) Salivary amylase

c) HCl

Answer : (i)

a) Bile – emulsiflcation of fats

b) Salivary amylase – digest starch in mouth

c) HCl – Activate pepsinogen by making medium acidic in stomata.

 

Question. Draw the diagram of alimentary canal of man and label it.
Answer : 

 

Question. With the help of labeled diagram, Discuss the mechanism of respiration in human beings.

Answer : Mechanism of Respiration – It occurs in following steps

a) Breathing – Taking in oxygen and expelling carbon – dioxide out is called breathing. It involves following steps –

(i) Inhalation – It is taking in oxygen. It occurs due to contraction of muscles attached to ribs. This lifts ribs and flatter diaphragm, which increase the volume of thoracic cavity. Hence the pressure inside the thoracic cavity decreases and air rushes inside of the lungs.

(ii) Exhalation – It is expelling of carbon – dioxide. It occurs due to relaxation of muscles attached to ribs and diaphragm is done shaped. This decreases the volume of thoracic cavity and decreases air pressure and expels out of the lung.

b) Exchange of gases – It takes place between the alveoli of lungs and surrounding blood capillaries.

c) Transport of gases in blood – Hemoglobin present in the blood transport. in blood. Oxygen is transport from the lungs to the body cells in the form of any hemoglobin.

d) Oxidation of food – Break down of glucose molecules which produce energy. It occurs is into chondria.

 

Question. Blood from superior vena cava flows into------------
(a)Right atrium
(b) Right ventricle
(c) Left atrium
(d) Left ventricle
Answer : Correct option(a)

 

Question. Describe an experiment to prove that carbon – dioxide is essential for the process of photosynthesis.

Answer : Experiment showing is essential for photosynthesis.
1) Take a potted plant with elongated leaves

2) Take an empty bottle and put a little amount of potassium hydroxide (KOH) in it.

3) Now cut the cork of the bottle into two parts and place it on one of the leaves of the potted plant in between the two parts of the cork.

4) Now put the bottle in the presence of sunlight 72 – 96 hours.

5) Now test the leaf for the presence of starch.

 

Question. Write three types of blood vessels. Give one important feature of each.
Answer : (i)Arteries-No valves, thick walled, carry oxygenated blood away from heart.
(ii)Veins-Presence of valves, thin walled, carry deoxygenated blood towards heart.
(iii)Capillaries-Very fine blood vessels, found in tissues, site for material exchange

 

Question. Describe the structure and functioning of nephron.

Answer : Each nephron is a cluster of very thin-walled blood capillaries. Each capillary cluster in the kidney called glomerulus is associated with the cup shaped Bowman’s capsule that collects the filtered urine.

Nephron filters the blood in order to remove nitrogenous waste. They also absorb some useful substance such as glucose, amino acids, minerals and major amount of water from filtrate.

 

Question. How does aerobic respiration differs from anaerobic respiration?
Answer : 

 

Question. Describe double circulation in human beings. Why is it necessary?

Answer : In mammals and birds the blood goes through the heart twice during each cycle. This is known as double circulation.

Deoxygenated blood which enters right auricle and then it enters the right ventricle from where it is pumped to lungs for oxygenation. From lungs after oxygenation it comes to left auricle and then enters left ventricle from where it is pumped to various parts of body.

Such system of circulation does not allow mixing of oxygenated and deoxygenated blood which allows efficient supply of oxygen to the body.

 

Question. Out of a goat and tiger, which one will have a longer small intestine? Justify your answer.
Answer : Goat because herbivores eating grass needs a longer small intestine to allow the cellulose to be digested.

 

 

 

Class 10 Science Life Process Notes and Questions

Question: How is small intestine deigned to absorb digested
Answer : The inner lining of small intestine has numerous finger-like projections called villi which increase the surface area for absorption. The villi are richly supplied with blood vessels which transport the absorbed food to each and every cells of the body. Where, it is utilized to obtaining energy and repair of old tissues.

Question: How are lungs designed in human beings to maximize the area of exchange of gases
Answer : Lungs have some adaptations in them so that eficient exchanges of gases take place. The adaptations are –
a) Increased surface area
b) Very fine and delicate surface for easy exchange of oxygen and carbon dioxide
c) Mechanism for moving the air in and out of respiratory surface where the oxygen is absorbed

Question: Dark reaction of photosynthesis does not need light. Do plants undergo dark reaction at night explain.
Answer : Dark reaction does not mean that it occurs in the absence of light i.e., at night. Infact these reactions do not depend on light energy and occur simultaneously with light reaction.

Question: What are the functions of lymph in our body?
Answer : Functions of lymph area)
It returns tissue fluid from interstitial space into the blood.
b) It collects carbon dioxide, waste products and metabolites from tissues via tissue fluid.
c) Lymph has lymphocytes (WBC’S), the lymph provides in immunity to the body and fight against the invading organisms.

Question: With the help of labelled diagram, discuss the structure of cross – section of leaf.
Answer : Leaf has two parts:
(i) Epidermis – Outermost layer of cell is called epidermis. Lower epidermis has small pores in between cells called stomata.
(ii) Mesophyll – Parenchymatons cells containing chloroplast is called mesophyll. It is two types – palisade and spongy parenchyma.

Question: How is haemoglobin associated with respiration explained?
Answer : Transportation of oxygen and carbon – dioxide occurs with the help of respiratory pigment haemoglobin. Haemoglobin is a red pigment having very high affinity for oxygen. Oxygen is transported from the lungs to the body cells in the form of oxyhemoglobin. Carbon – dioxide is transported from the body cells to the lungs in the form of carbamino – haemoglobin

Question: What is “translocation”? Why it is essential for plants.
Answer : Transportation of organic solutes in the plants is called translocation. It is necessary, because all the cells need food to carry out their vital functions. It occurs in upward as well as downward direction or to the storage organs of roots, fruits, seeds and to growing organs.

Question: What are the modes of excretion in plants?
Answer : Modes of excretion in plants are –
a) The plants get rid of excess water by transpiration.
b) The only major gases excretory product of plants in oxygen. It is released from plants into the environment by diffusion.
c) Organic wastes of plants are stored within dead permanent tissues such as wood or within leaves or bark which are periodically removed.
d) The plants also excrete some wastes substances into the soil around them.
e) Many wastes products of plants are stored in cellular vacuoles.

Question: How is transpiration pull responsible for upward movement of water?
Answer : The leaves loose water in the form of water vapours through stomata by a process known as transpiration. Continuous transpiration creates a s suction in the water column of the xylem elements and it reaches unto the roots. This pull is called transpiration pull. Due to transpiration, the water column of the plant is pulled up from below to the top of the plant.

Question: Chloroplast are called energy convertors. Explain.
Answer : Chloroplasts are called energy convertors because they trap the solar energy and convert it into chemical energy.

Question: While eating you are advised not to talk Why are you advised so?
Answer : We are advised so because while eating some food particles might enter the wind pipe which can lead to choking.

Question: Name the respiratory organs of (i) fish (ii) mosquito (iii) earthworm.
Answer : Fish – gills
Mosquito – Trachea (air tubes)
Earthworm – moist skin

Question: If a person is working on a treadmill in a gymnasium, will it effect his rate of breathing? How?
Answer : Yes, it will affect his rate of breathing. The rate of breathing will become fast to supply more oxygen to meet the increased demand of energy.

Question: In the process of Photosynthesis food A is prepared which gets converted into food B. What are A and B? Why is A converted to B?
Answer : Food A is glucose and food B is Starch.
A is converted to B as B is insoluble form of carbohydrate. It is more compact and hence, suitable for storage.

Question: What is the function of digestive enzymes?
Answer : Enzymes break-down the various complex components of food into simple and soluble components so that they can be absorbed easily.

Question: Mucus is not used for churning the food or digesting it. Then why is it secreted in the stomach?
Answer : Mucus is secreted in the stomach to protect its inner lining form being damaged by HCI. Excessive secretion of HCI can damage the lining and lead to peptic ulcer.

Question: When we are asleep we are not performing any activity still our life processes are going on. Why?
Answer : “The maintenance functions of living organisms must go on even when they are not doing anything particular.” That is why the life processes are going on even while we are asleep or not performing any activity.

Question: We say that movement is a characteristic of living organisms but we always don’t see visible movements in plants. Comment.
Answer : We always don’t see visible movements in plants. It does not mean that they are not alive. Molecular movements take place in their body.

Question: Due to availability of less water, how does the plant cope up with lack of water in desert conditions?
Answer : They open their stomata at night and stomata remain closed during day time, to conserve moisture. 

Question: Why is the rate if breathing much faster in aquatic organisms than those of terrestrial organisms?
Answer : The aquatic organisms obtain oxygen dissolved in water. As compared to air, the availability of oxygen in water is fairly low. Hence, the aquatic organisms have to breathe faster as compared to the terrestrial organisms.

 

Answer the following questions :

1. Name the process required for the maintenance of life.

2. What is the function of stomata and how do they perform this function?

3. Which element is essential for the synthesis of proteins in plants?

4. How do the plants fulfill the requirement of nitrogen to make proteins?

5. Describe the nutrition process in Amoeba.

6. Name the enzyme present is saliva.

7. What are the secretions of gastric glands?

8. Name the muscle which regulate the exit of food from stomach?

9. Name the enzymes present in pancreatic Juice?

10. What causes the formation of cramps in our muscles?

11. Why does the rate of breathing in aquatic organisms is much faster than the terrestrial organism?

12. Name the respiratory pigment present in human beings?

13. Why does the ventricles have thick walls than atria?

14. Name the group of animals that have 3 chambered and 2 chambered heart?