(a) Define nutrition. Why is nutrition necessary for an organism ?
(b) What are the different modes of nutrition ? Explain with one example of each mode of nutrition.
(c) Name the mode of nutrition in (i) roundworm, and (ii) Plasmodium.
(a) Nutrition is defined as a process of intake of nutrients (like carbohydrates, fats, proteins, minerals, vitamins and water) by an organism as well as the utilisation of these nutrients by the organism. Nutrition is necessary for an organism as it provides energy to them from the food they eat. (b) There are mainly two modes of nutrition:
(i) Autotrophic – Autotrophic nutrition is that mode of nutrition in which an organism makes its own food from the simple inorganic materials like carbon dioxide and water present in the surroundings (with the help of sunlight energy). Example: Green plants obtain food by autotrophic nutrition.
(ii) Heterotrophic – Heterotrophic nutrition is that mode of nutrition in which an organism cannot make its own food from simple inorganic materials like carbon dioxide and water, and depends on other organisms for its food. Example: All animals obtain food by heterotrophic nutrition.
(c) The mode of nutrition in
(i) round worm and
(ii) plasmodium is parasitic nutrition.
(a) What are heterotrophs ? Give one example of heterotrophs.
(b) What is the difference between autotrophic nutrition and heterotrophic nutrition ?
In the experiment "Light is essential for photosynthesis", why does the uncovered part of the leaf turn blue-black after putting iodine solution?
Name the final product/products obtained in the anaerobic respiration, if it takes place :
(a) in a plant (like yeast).
(b) in an animal tissue (like muscles).
Write correct sequence of four steps of method for the preparation of temporary mount of a stained leaf peel.
(a) What is meant by breathing? What happens to the rate of breathing during vigorous exercise and why?
(b) Define translocation with respect to transport in plants. Why is it essential for plants? Where in plants are the following synthesised?
(i) Sugar (iii) Hormone
(a) Name the pigment in leaves which absorbs sunlight energy.
(b) What is the colour of this pigment ?
Name the enzyme present in human saliva. What type of food material is digested by this enzyme ?
Define (i) saprophytic nutrition (ii) parasitic nutrition, and (iii) holozoic nutrition. Give one example of each type.
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.
Name the substance whose build up in the muscles during vigorous physical exercise may cause cramps.
Name the areas in a woody stem through which respiratory exchange of gases takes place.
In mammals and birds why is it necessary to separate oxygenated and de-oxygenated blood ?
(a) Draw a diagram of human respiratory system and label the following:
(i) part where air is filtered by fine hair and mucus
(ii) part which terminates in balloon – like structures
(iii) balloon – like structures where exchange of gases takes place. (iv) part which separates chest cavity from abdominal cavity.
(b) Why is the rate of breathing in aquatic organisms much faster than in terrestrial organisms?
Name the intermediate and the end products of glucose breakdown in aerobic respiration.
In addition to carbon dioxide and water, state two other conditions necessary for the process of photosynthesis to take place.
Apart from sunlight and chlorophyll, what other things are required to make food by photosynthesis ?
(a) What is the role of hydrochloric acid in our stomach ?
(b) What is the function of enzymes in the human digestive system ?
In the lungs :
(a) what substance is taken into the body ?
(b) what substance is removed from the body ?
(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 ?
Name the correct substrates for the following enzymes
(a) Trypsin (b) Amylase (c) Pepsin (d) Lipase