Class 7 Science - Chapter Nutrition in Animals NCERT Solutions | Why do we get instant energy from glucos

Write one similarity and one difference between the nutrition in amoeba and human beings.

Label Fig. 2.11 of the digestive system.

Can we survive only on raw, leafy vegetables/grass? Discuss.

Which part of the digestive canal is involved in:
(i) absorption of food ________________.
(ii) chewing of food ________________.
(iii) killing of bacteria ________________.
(iv) complete digestion of food ________________.
(v) formation of faeces ________________.

Match the items of Column I with suitable items in Column II
Column I                                  Column II
(a) Salivary gland                     (i) Bile juice secretion
(b) Stomach                             (ii) Storage of undigested food
(c) Liver                                    (iii) Saliva secretion
(d) Rectum                               (iv) Acid release
(e) Small intestine                    (v) Digestion is completed
(f ) Large intestine                    (vi) Absorption of water
                                                 (vii) Release of faeces

Name the type of carbohydrate that can be digested by ruminants but not by humans. Give the reason also.

Match the items of Column I with those given in Column II:
Column I                            Column II
Food components               Product(s) of digestion
Carbohydrates                    Fatty acids and glycerol
Proteins                              Sugar
Fats                                     Amino acids

Where is the bile produced? Which component of the food does it help to digest?

Tick (✓) mark the correct answer in each of the following:

(a) Fat is completely digested in the
     (i) stomach (ii) mouth (iii) small intestine (iv) large intestine

(b) Water from the undigested food is absorbed mainly in the
     (i) stomach (ii) foodpipe (iii) small intestine (iv) large intestine

Fill in the blanks:
(a) The main steps of nutrition in humans are __________, __________, __________, _________ and __________.
(b) The largest gland in the human body is __________.
(c) The stomach releases hydrochloric acid and ___________ juices which act on food.
(d) The inner wall of the small intestine has many finger-like outgrowths called _________.
(e) Amoeba digests its food in the ____________ .

State similarities and differences between the laboratory thermometer and the clinical thermometer.

State differences between acids and bases.

Classify the changes involved in the following processes as physical or chemical changes:
(a) Photosynthesis
(b) Dissolving sugar in water
(c) Burning of coal
(d) Melting of wax
(e) Beating aluminium to make aluminium foil
(f ) Digestion of food

Name the elements that determine the weather of a place.

Fill the missing word in the blank spaces in the following statements:

(a) Wind is——————air.
(b) Winds are generated due to —————— heating on the earth.
(c) Near the earth’s surface __________air rises up whereas ___________ air comes down.
(d) Air moves from a region of ——— pressure to a region of ———.

In addition to the rock particles, the soil contains

(i) air and water
(ii) water and plants
(iii) minerals, organic matter, air and water
(iv) water, air and plants

Why does an athlete breathe faster and deeper than usual after finishing the race?

Match structures given in Column I with functions given in Column II.

Column I                           Column II
(i) Stomata                        (a) Absorption of water
(ii) Xylem                           (b) Transpiration
(iii) Root hairs                    (c) Transport of food
(iv) Phloem                        (d) Transport of water
                                          (e) Synthesis of carbohydrates

Fill in the blanks:

(a) Production of new individuals from the vegetative part of parent is called_____________.
(b) A flower may have either male or female reproductive parts. Such a flower is called_____________.
(c) The transfer of pollen grains from the anther to the stigma of the same or of another flower of the same kind is known as _____________.
(d) The fusion of male and female gametes is termed as _____________.
(e) Seed dispersal takes place by means of _____________, _____________ and _____________.

Classify the following as motion along a straight line, circular or oscillatory motion:

(i) Motion of your hands while running.
(ii) Motion of a horse pulling a cart on a straight road.
(iii) Motion of a child in a merry-go-round.
(iv) Motion of a child on a see-saw.
(v) Motion of the hammer of an electric bell.
(vi) Motion of a train on a straight bridge.

Show with the help of a sketch that the plants are the ultimate source of food.

Which of the two changes frequently, weather or climate?

Give a brief description of the process of synthesis of food in green plants.

The mountaineers carry oxygen with them because:

(a) At an altitude of more than 5 km there is no air.
(b) The amount of air available to a person is less than that available on the ground.
(c) The temperature of air is higher than that on the ground.
(d) The pressure of air is higher than that on the ground.

Take three test-tubes. Fill æth of each with water. Label them A, B and C. Keep a snail in test-tube A, a water plant in test-tube B and in C, keep snail and plant both. Which test-tube would have the highest concentration of CO₂?

Outline your role as an active citizen in relation to sanitation.

A carnivore with stripes on its body moves very fast while catching its prey. It is likely to be found in

(i) polar regions          (ii) deserts
(iii) oceans                 (iv) tropical rainforests

Explain how soil pollution and soil erosion could be prevented.

The bulb in the circuit shown in Fig.14.23 does not glow. Can you identify the problem? Make necessary changes in the circuit to make the bulb glow.

Why does an athlete breathe faster and deeper than usual after finishing the race?