Biology

Life Processes

Question:

(a) Photosynthesis converts energy X into energy Y. What are X and Y ?
(b) State the various steps involved in the process of photosynthesis.

Answer:

(a) X is sunlight energy and Y is chemical energy.
(b) The photosynthesis takes place in the following three steps;
(i) Absorption of sunlight energy by chlorophyll.
(ii) Conversion of light energy into chemical energy and splitting of water into hydrogen and oxygen by light energy.
(iii) Reduction of carbon dioxide by hydrogen to form carbohydrates like glucose by utilising the chemical energy

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Life Processes

Q 1.

What are the different ways in which glucose is oxidised to provide energy in various organisms ? Give one example of each.

Q 2.

What are the functions of the liver and the pancreas?

Q 3.

What will happen if mucus is not secreted by the gastric glands?

Q 4.

How are the alveoli designed to maximise the exchange of gases?

Q 5.

Define (i) saprophytic nutrition (ii) parasitic nutrition, and (iii) holozoic nutrition. Give one example of each type.

Q 6.

Other than chlorophyll, which other pigment is necessary for photosynthesis?

Q 7.

What is the advantage of having four chambered heart?

Q 8.

Why and how does water enter continuously into the root xylem?

Q 9.

(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 ?

Q 10.

What is saliva? State its role in the digestion of food.

Q 11.

All the animals can be divided into three groups on the basis of their eating habits. Name the three groups.

Q 12.

(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.

Q 13.

Do all cells use oxygen to produce energy ?

Q 14.

Name an animal which absorbs oxygen through its moist skin.

Q 15.

The trachea divides into two tubes at its lower end. What is the name of these tubes ?

Q 16.

Where does the blood absorb oxygen in the human body ?

Q 17.

Name the red pigment which carries oxygen in blood.

Q 18.

What type of respiration takes place in human muscles during vigorous physical exercise ? Give reason for your answer.

Q 19.

Describe the process of respiration in State whether it is anaerobic respiration or aerobic respiration.

Q 20.

(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 ?

Q 21.

Define nutrition? What are the different modes of nutrition?

Q 22.

Name the factors, which affect photosynthesis.

Q 23.

Give two points of differences between respiration in plants and respiration in animals.

Q 24.

What are the living organisms that cannot make their own food called?

Q 25.

What are the necessary conditions for autotrophic nutrition and what are its byproducts?

Q 26.

What are the differences between aerobic and anaerobic respiration? Name some organisms that use the anaerobic mode of respiration.

Q 27.

Describe double circulation in human beings. Why is it necessary?

Q 28.

Is nutrition' a necessity for an organism? Discuss.

Q 29.

What is the significance of emulsification of fats?

Q 30.

Explain the role of mouth in digestion of food.

Q 31.

Name the correct substrates for the following enzymes
(a) Trypsin (b) Amylase (c) Pepsin (d) Lipase

Q 32.

Explain the process of nutrition in Amoeba.

Q 33.

Name the acid presents in the following:
(i) Tomato (ii) Vinegar (iii) Tamarind

Q 34.

State the role of the following in human digestive system :
(i) Digestive enzymes (ii) Hydrochloric acid (iii) Villi

Q 35.

Draw a diagram of human respiratory system and label on it :
(i) Diaphragm (ii) Larynx

Q 36.

Name the intermediate and the end products of glucose breakdown in aerobic respiration.

Q 37.

Which of the following is an autotroph ? Green plant or Man

Q 38.

(a) Name a gas used in photosynthesis.
(b) Name a gas produced in photosynthesis.

Q 39.

(a) Name the pigment in leaves which absorbs sunlight energy.
(b) What is the colour of this pigment ?

Q 40.

Name the green pigment present in the leaves of a plant.

Q 41.

What substance is mixed with food in the mouth during chewing by the teeth ?

Q 42.

(a) What are heterotrophs ? Give one example of heterotrophs.
(b) What is the difference between autotrophic nutrition and heterotrophic nutrition ?

Q 43.

What substances are contained in pancreatic juice ? What are their functions ?

Q 44.

(a) What is photosynthesis ?
(b) Write a chemical equation to show the process of photosynthesis in plants.
(c) Explain the mechanism of photosynthesis.

Q 45.

Name one substance which is produced in anaerobic respiration by an organism but not in aerobic respiration.

Q 46.

Name one organism which can live without oxygen.

Q 47.

Name the substance whose build up in the muscles during vigorous physical exercise may cause cramps.

Q 48.

Which gases are exchanged in your lungs ?

Q 49.

(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 ?

Q 50.

Define a herbivore and a carnivore.