Name the substance whose build up in the muscles during vigorous physical exercise may cause cramps.
Lactic acid.
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.
State the role of the following in human digestive system :
(i) Digestive enzymes (ii) Hydrochloric acid (iii) Villi
(a) Photosynthesis converts energy X into energy Y. What are X and Y ?
(b) State the various steps involved in the process of photosynthesis.
(a) How does carbon dioxide from the air enter the leaves of a plant to be used in photosynthesis ?
(b) How does water from the soil reach the leaves of a plant to be used in photosynthesis ?
Name the substance whose build up in the muscles during vigorous physical exercise may cause cramps.
Name the correct substrates for the following enzymes
(a) Trypsin (b) Amylase (c) Pepsin (d) Lipase
a) Leaves of a healthy potted plant were coated with vaseline to block the stomata. Will this plant remain healthy for long? State three reasons for your answer.
(b) State any two differences between autotrophic nutrition and heterotrophic nutrition.
Name the intermediate and the end products of glucose breakdown in aerobic respiration.
Which of the following type of energy is used by living organisms to perform vital life processes ?
Kinetic energy, Chemical energy, Potential energy, Nuclear energy
Arrange the following processes involved in the nutrition in animals in the correct order (in which they take place):
Assimilation, Egestion, Ingestion, Absorption, Digestion
A Give one reason why multicellular organisms require special organs for exchange of gases between their body and their environment. :
Name the following :
(a) The process in plants which converts light energy into chemical energy.
(b) Organisms that cannot prepare their own food.
(c) Organisms that can prepare their own food.
(d) The cell organelle where photosynthesis occurs.
(e) The cells which surround a stomatal pore.
(f) An enzyme secreted by gastric glands in stomach which acts on proteins.
State the three common features of all the respiratory organs like skin, gills and lungs.
(a) Draw a diagram to show open stomatal pore and label on it:
(i) guard cells
(ii) chloroplast
(b) State two functions of stomata.
(c) How do guard cells regulate the opening and closing of stomatal pore?
In the experiment "Light is essential for photosynthesis", why does the uncovered part of the leaf turn blue-black after putting iodine solution?
(a) What is common for Cuscuta, ticks and leeches ?
(b) Name the substances on which the following enzymes act in the human digestive system :
(i) Trypsin (ii) Amylase (iii) Pepsin (iv) Lipase
(c) Why does absorption of digested food occur mainly in the small intestine ?
(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 ?
What are the differences between aerobic and anaerobic respiration? Name some organisms that use the anaerobic mode of respiration.
"All plants give out oxygen during day and carbon dioxide during night". Do you agree with this statement? Give reason.