(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 ?
(a) When air passes through the nasal passage, the dust particles and other impurities present in it are trapped by nasal hair and mucus so that clean air goes into the lungs.
(b) Trachea does not collapse even when there is no air in it because it is supported by rings of soft bones called cartilage.
(c) During the process of ‘breathing in’ the air sacs or alveoli of the lungs get filled with air contain.
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.
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 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.
Name one substance which is produced in anaerobic respiration by an organism but not in aerobic respiration.
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.
(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?
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
Draw a neat diagram of excretory system of human beings and label on it:
(i) Left kidney (ii) Urinary bladder
Name the green dot like structures in some cells observed by a student when a leaf peel was viewed under a microscope. What is this green colour due to?
In addition to carbon dioxide and water, state two other conditions necessary for the process of photosynthesis to take place.