Biology

Life Processes

Question:

(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.

Answer:

(a) If all the green plants disappear from the earth, then all the organisms (herbivores, carnivores and omnivores) will die due to starvation as green plants are the source of food for all organisms.
(b) When photosynthesis occurs during the day, the carbon dioxide released by plants by respiration is all used up and not released. Similarly, some of the oxygen produced during photosynthesis is used up in respiration. Since the plant is releasing carbon dioxide and taking in oxygen even during the day, it means that no photosynthesis is taking place.

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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.

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

Q 4.

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

Q 5.

(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 6.

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

Q 7.

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

Q 8.

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

Q 9.

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

Q 10.

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

Q 11.

Define nutrition? What are the different modes of nutrition?

Q 12.

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

Q 13.

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

Q 14.

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

Q 15.

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

Q 16.

Is nutrition' a necessity for an organism? Discuss.

Q 17.

What is the advantage of having four chambered heart?

Q 18.

Explain the role of mouth in digestion of food.

Q 19.

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

Q 20.

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

Q 21.

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

Q 22.

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

Q 23.

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

Q 24.

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

Q 25.

Do all cells use oxygen to produce energy ?

Q 26.

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

Q 27.

Name one organism which can live without oxygen.

Q 28.

Name an animal which absorbs oxygen through its moist skin.

Q 29.

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

Q 30.

Where does the blood absorb oxygen in the human body ?

Q 31.

Name the red pigment which carries oxygen in blood.

Q 32.

Which gases are exchanged in your lungs ?

Q 33.

(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 34.

Name the factors, which affect photosynthesis.

Q 35.

Define a herbivore and a carnivore.

Q 36.

Define breathing.

Q 37.

In which kind of respiration is more energy released?

Q 38.

State the function of epiglottis.

Q 39.

What is compensation point?

Q 40.

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

Q 41.

What is the significance of emulsification of fats?

Q 42.

Explain the process of nutrition in Amoeba.

Q 43.

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

Q 44.

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

Q 45.

Mention the raw materials required for photosynthesis.

Q 46.

Draw a neat diagram of excretory system of human beings and label on it:
(i) Left kidney (ii) Urinary bladder

Q 47.

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?

Q 48.

What is translocation'in plants?

Q 49.

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

Q 50.

In addition to carbon dioxide and water, state two other conditions necessary for the process of photosynthesis to take place.