Class 7 Science - Chapter Reproduction in Plants NCERT Solutions | How does the process of fertilisation ta

Sketch the reproductive parts of a flower.

Match items in Column I with those in Column II:

Column I                             Column II
(a) Bud                                  (i) Maple
(b) Eyes                                (ii) Spirogyra
(c) Fragmentation                 (iii) Yeast
(d) Wings                              (iv) Bread mould
(e) Spores                             (v) Potato
                                              (vi) Rose

Describe the various ways by which seeds are dispersed.

Describe the different methods of asexual reproduction. Give examples.

Explain the difference between self-pollination and cross-pollination.

State the main difference between asexual and sexual reproduction.

Explain what you understand by sexual reproduction.

Tick the correct answer:

(a) The reproductive part of a plant is the
(i) leaf    (ii) stem    (iii) root    (iv) flower

(b) The process of fusion of the male and the female gametes is called
(i) fertilisation          (ii) pollination
(iii) reproduction      (iv) seed formation

(c) Mature ovary forms the
(i) seed                   (ii) stamen
(iii) pistil                  (iv) fruit

(d) A spore producing plant is
(i) rose                   (ii) bread mould
(iii) potato              (iv) ginger

(e) Bryophyllum can reproduce by its
(i) stem                  (ii) leaves
(iii) roots                (iv) flower

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 _____________.

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

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.

Why do organisms need to take food?

Which type of lens forms always a virtual image?

A simple pendulum takes 32 s to complete 20 oscillations. What is the time period of the pendulum?

Describe the function of the heart.

Blue litmus paper is dipped in a solution. It remains blue. What is the nature of the solution? Explain.

Here is a crossword puzzle: Good luck!

Across
3. Liquid waste products
4. Solid waste extracted in sewage treatment
6. A word related to hygiene
8. Waste matter discharged from human body

Down
1. Used water
2. A pipe carrying sewage
5. Micro-organisms which causes cholera
7. A chemical to disinfect water

Ammonia is found in many household products, such as window cleaners. It turns red litmus blue. What is its nature?

Choose the correct option. The total water

(i) in the lakes and rivers of the world remains constant.
(ii) under the ground remains constant.
(iii) in the seas and oceans of the world remains constant.
(iv) of the world remains constant.

Explain the function of bar screens in a wastewater treatment plant.

How will you help your neighbours in case cyclone approaches your village/town?

Will the compass needle show deflection when the switch in the circuit shown by Fig.14.24 is closed?