Why is transport of materials necessary in a plant or in an animal? Explain.
Transport in organism like plants and animals is very necessary as it absorbs all essential components and transport them to all parts of the body. The water and minerals from soil enters the plant through the roots and then pass into the xylem that is from the soil to the uppermost leaves. This upward movement of minerals and water against the gravitational force through the xylem is known as ascent of sap in the plants. Transport of materials is necessary in both plants and animals because every cell needs a regular supply of mineral nutrients.
The uptake of inorganic nutrients from the soil is mineral nutrition which is very important to complete their growth and life cycle and in animals; the food that we eat is broken down into smaller components that is absorbed by the cells. The oxygen that we intake is also transported to all the cells of the body. Our body also requires the removal of waste materials such as carbon dioxide in the breathing process. For the transport of food, oxygen and wastes; our body has a specialised transport system. Similarly, in plants, the transport of water and food is accomplished with the help of xylem and phloem.
What are stomata? Give two functions of stomata.
Draw a diagram of the human excretory system and label the various parts.
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
Describe the function of the heart.
Does transpiration serve any useful function in the plants? Explain.
What are the components of blood?
What will happen if there are no platelets in the blood?
Why is it necessary to excrete waste products?
Why is blood needed by all the parts of a body?
What makes the blood look red?
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?
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.
Why do organisms need to take food?
Which one of the following place is unlikely to be affected by a cyclone.
(i) Chennai (ii) Mangaluru (Mangalore) (iii) Amritsar (iv) Puri
Match the items given in Column I with those in Column II:
Column I Column II
Chlorophyll Bacteria
Nitrogen Heterotrophs
Amarbel Pitcher plant
Animals Leaf
Insects Parasite
Show the shape of the distance-time graph for the motion in the following cases:
(i) A car moving with a constant speed.
(ii) A car parked on a side road.
Suppose the two photographs, shown in Fig. 13.1 and Fig. 13.2, had been taken at an interval of 10 seconds. If a distance of 100 metres is shown by 1 cm in these photographs, calculate the speed of the blue car.
Explain the relationship between sanitation and disease.
Describe the various ways by which seeds are dispersed.
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.
State two differences between a convex and a concave lens.
Why should we worry about the conditions and issues related to forests far from us?
Explain what you understand by sexual reproduction.