Why and how does water enter continuously into the root xylem?
Cells of root are in close contact with soil and so actively take up ions. The ion- concentration, increases inside the root and hence osmotic pressure increases the movement of water from the soil into the root which occurs continuously. Transpiration also plays a big role in causing, osmotic pressure.
What are the different ways in which glucose is oxidised to provide energy in various organisms ? Give one example of each.
Define (i) saprophytic nutrition (ii) parasitic nutrition, and (iii) holozoic nutrition. Give one example of each type.
(a) Draw a diagram of excretory system in human beings and label the following parts. Aorta, kidney, urinary bladder and urethra.
(b) How is urine produced and eliminated ?
All the animals can be divided into three groups on the basis of their eating habits. Name the three groups.
(a) What would happen if all the green plants disappear from the earth ?
(b) If a plant is releasing carbon dioxide and taking in oxygen during the day, does it mean that there is no photosynthesis occurring ? Justify your answer.
What type of respiration takes place in human muscles during vigorous physical exercise ? Give reason for your answer.
Describe the process of respiration in State whether it is anaerobic respiration or aerobic respiration.
Give two points of differences between respiration in plants and respiration in animals.
What are the necessary conditions for autotrophic nutrition and what are its byproducts?
What are the differences between aerobic and anaerobic respiration? Name some organisms that use the anaerobic mode of respiration.
Name the correct substrates for the following enzymes
(a) Trypsin (b) Amylase (c) Pepsin (d) Lipase
State the role of the following in human digestive system :
(i) Digestive enzymes (ii) Hydrochloric acid (iii) Villi
Name the intermediate and the end products of glucose breakdown in aerobic respiration.
(a) Name the pigment in leaves which absorbs sunlight energy.
(b) What is the colour of this pigment ?
(a) What are heterotrophs ? Give one example of heterotrophs.
(b) What is the difference between autotrophic nutrition and heterotrophic nutrition ?
Name one substance which is produced in anaerobic respiration by an organism but not in aerobic respiration.
Name the substance whose build up in the muscles during vigorous physical exercise may cause cramps.
(a) What is meant by aquatic animals and terrestrial animals ?
(b) From where do the aquatic animals and terrestrial animals obtain oxygen for breathing and respiration ?
(a) Explain how, the air we breathe in gets cleaned while passing through the nasal passage.
(b) Why do the walls of trachea not collapse when there is less air in it ?
(c) How are oxygen and carbon dioxide exchanged in our body during respiration ?
(d) How are lungs designed in human beings to maximise the exchange of gases ?