Explain the difference between self-pollination and cross-pollination.
Pollination is the transfer of pollen grains from the anther to the stigma of the flower which can be achieved by biotic (insects, birds etc.) and abiotic (wind, water etc.) pollinating agents. On the basis of pollinating mechanism, plants can be grouped into two mating systems: self- pollinated and cross- pollinated.
Self- Pollination | Cross Pollination |
1. The pollen grain moves to the female part of the same flower or different flower of the same plant species. | 1. The pollen grains are transferred to the flower present on the different plant. |
2. Transfer to the same flower is autogamy; and to another flower on the same plant is geitonogamy. | 2. Cross- pollination is also known as allogamy. |
3. No genetic variation occurs. | 3. High genetic variation are found. |
4. Identical species are created, i.e. no new species are formed. | 4. New species are formed. |
5. Transfer of pollen grains are limited. | 5. Transfer of pollen grains unlimited, i.e. in large amount. |
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.
How does the process of fertilisation take place in flowers?
Describe the different methods of asexual reproduction. Give examples.
Explain what you understand by sexual reproduction.
State the main difference between asexual and 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?
Is the distilled water acidic/basic/neutral? How would you verify it?
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.
Describe the process of neutralisation with the help of an example.
Three liquids are given to you. One is hydrochloric acid, another is sodium hydroxide and third is a sugar solution. How will you identify them? You have only turmeric indicator.
Blue litmus paper is dipped in a solution. It remains blue. What is the nature of the solution? Explain.
Describe the function of the heart.
Ammonia is found in many household products, such as window cleaners. It turns red litmus blue. What is its nature?
Mark ‘T’ if the statement is true and ‘F’ if it is false:
(i) Nitric acid turn red litmus blue. (T/F)
(ii) Sodium hydroxide turns blue litmus red. (T/F)
(iii) Sodium hydroxide and hydrochloric acid neutralise each other and form salt and water. (T/F)
(iv) Indicator is a substance which shows different colours in acidic and basic solutions. (T/F)
(v) Tooth decay is caused by the presence of a base. (T/F)
Tick the correct answer:
(a) In cockroaches, air enters the body through
(i) lungs (ii) gills
(iii) spiracles (iv) skin
(b) During heavy exercise, we get cramps in the legs due to the accumulation of
(i) carbon dioxide (ii) lactic acid
(iii) alcohol (iv) water
(c) Normal range of breathing rate per minute in an average adult person at rest is:
(i) 9ñ12 (ii) 15ñ18
(iii) 21ñ24 (iv) 30ñ33
(d) During exhalation, the ribs
(i) move outwards (ii) move downwards
(iii) move upwards (iv) do not move at all
Explain why:
(a) An antacid tablet is taken when you suffer from acidity.
(b) Calamine solution is applied on the skin when an ant bites.
(c) Factory waste is neutralised before disposing it into the water bodies.