How are the alveoli designed to maximise the exchange of gases?
Alveoli are small pouches or sacs like structure. They are surrounded by blood capillaries. Thus a large amount of air is brought in contact with the air in the lungs. More than millions of alveoli are present in the lungs. The presence of millions of alveoli in the lungs provides a very large surface area for the exchange of gases. The availability of large surface area maximises the exchange of gases.
What are the different ways in which glucose is oxidised to provide energy in various organisms ? Give one example of each.
(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 ?
Define (i) saprophytic nutrition (ii) parasitic nutrition, and (iii) holozoic nutrition. Give one example of each type.
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 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
Name the intermediate and the end products of glucose breakdown in aerobic respiration.
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.
Name one substance which is produced in anaerobic respiration by an organism but not in aerobic respiration.
(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 ?
What are the necessary conditions for autotrophic nutrition and what are its byproducts?
State the role of the following in human digestive system :
(i) Digestive enzymes (ii) Hydrochloric acid (iii) Villi