State the main difference between asexual and sexual reproduction.
Asexual Reproduction | Sexual Reproduction |
1. It does not involve gametes formation. | 1. It involves gamete formation. |
2. Offspring will be genetically identical to its parents. | 2. Offspring will be genetically identical to the different parents. |
3. No fertilization occurs. | 3. Fertilization takes place. |
4. Characteristics of only one parent are inherited. | 4. Characteristics of both parents are inherited. |
5. Multiplication is very rapid and takes less time. |
5. Multiplication is not so rapid and takes a longer time to complete. |
6. The number of offspring produced in various forms. | 6. The number of offspring produced in lower amount comparatively. |
7. No evolutionary occurs. | 7. Evolution takes place by the mutation. |
8. Bacterial fission, fragmentation, spore formation, budding or agamospermy are different types of asexual reproduction. | 8. Sexual reproduction occurs through the formation of sexual spores. |
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.
Explain the difference between self-pollination and cross-pollination.
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?
Match the following :
(i) Land breeze blows during (a) summer
(ii) Sea breeze blows during (b) winter
(iii) Dark coloured clothes are preferred during (c) day
(iv) Light coloured clothes are preferred during (d) night
Match the items given in Column I with one or more items of Column II.
Column I Column II
(a) A plane mirror (i) Used as a magnifying glass.
(b) A convex mirror (ii) Can form image of objects spread over a large area.
(c) A convex lens (iii) Used by dentists to see enlarged image of teeth.
(d) A concave mirror (iv) The image is always inverted and magnified. (e) A concave lens (v) The image is erect and of the same size as the object.
(vi) The image is erect and smaller in size than the object.
Explain the role of forest in maintaining the balance between oxygen and carbon dioxide in the atmosphere.
Draw a diagram of the human excretory system and label the various parts.
Fill in the blanks:
(a) Green plants are called _________________ since they synthesise their own food.
(b) The food synthesised by the plants is stored as _________________.
(c) In photosynthesis solar energy is captured by the pigment called ___________.
(d) During photosynthesis plants take in ______________________ and release __________________.
Micro-organisms act upon the dead plants to produce
(i) sand (ii) mushrooms (iii) humus (iv) wood
Name two chemicals used to disinfect water.
Explain, with examples, why we find animals of certain kind living in particular climatic conditions.
Explain how painting of an iron gate prevents it from rusting.
When baking soda is mixed with lemon juice, bubbles are formed with the evolution of a gas. What type of change is it? Explain.