Biology

Life Processes

Question:

Is nutrition' a necessity for an organism? Discuss.

Answer:

Food is required for the following purposes:
(i) It provides energy for the various metabolic processes in the body.
(ii) It is essential for the growth of new cells and repair or replacement of worn out cells.
(iii) It is needed to develop resistance against various diseases.

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Life Processes

Q 1.

Define (2) saprophyte, and (22) parasite. Name two saprophytes and two parasites.

Q 2.

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

Q 3.

How does Amoeba engulf the food particle ?

Q 4.

(a) Which part of the body secretes bile ? Where is bile stored ? What is the function of bile ?
(b) What is trypsin ? What is its function ?

Q 5.

Explain why, it is dangerous to inhale air containing carbon monoxide.

Q 6.

Is nutrition' a necessity for an organism? Discuss.

Q 7.

What are the final products after digestion of carbohydrates and proteins?

Q 8.

Name the process in plants where water is lost as water vapour. :

Q 9.

Apart from sunlight and chlorophyll, what other things are required to make food by photosynthesis ?

Q 10.

Where is chlorophyll mainly present in a plant ?

Q 11.

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

Q 12.

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.

Q 13.

Name two animals which breathe through gills.

Q 14.

State whether the following statements are true or false :
(a) During respiration, the plants take C02 and release 02.
(b) Energy can be produced in cells without oxygen.
(c) Fish and earthworm exchange gases during respiration in the same way.

Q 15.

Explain why, plants have low energy needs as compared to animals.

Q 16.

Explain how, it would benefit deep sea divers if humans also had gills.

Q 17.

What is the mode of nutrition in fungi?

Q 18.

What are the functions of the liver and the pancreas?

Q 19.

In which kind of respiration is more energy released?

Q 20.

How do the guard cells regulate opening and closing of stomatal pores?

Q 21.

A Give one reason why multicellular organisms require special organs for exchange of gases between their body and their environment. :

Q 22.

From which part of the body, undigested food is egested in Amoeba ?

Q 23.

What is the name of tiny projections on the inner surface of small intestine which help in absorbing the digested food ?

Q 24.

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

Q 25.

What is the name of tiny air-sacs at the end of smallest bronchioles in the lungs ?

Q 26.

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).

Q 27.

State the three common features of all the respiratory organs like skin, gills and lungs.

Q 28.

From where do the following take in oxygen?
(i) prawn (ii) rat.
Solution:

Q 29.

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

Q 30.

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

Q 31.

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

Q 32.

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

Q 33.

List three characteristics of lungs which make it an efficient respiratory surface.

Q 34.

(a) Draw a sectional view of the human heart and label on it – Aorta, Right ventricle and Pulmonary veins.
(b) State the functions of the following components of transport system:
(i) Blood (ii) Lymph

Q 35.

Name the biological catalysts which bring about chemical digestion of food.

Q 36.

(a) Define a nutrient. Name four important nutrients present in our food.
(b) What are the various types of heterotrophic nutrition ?

Q 37.

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

Q 38.

What are the functions of liver and pancreas in the human digestive system ?

Q 39.

Do all cells use oxygen to produce energy ?

Q 40.

Name one organism which can live without oxygen.

Q 41.

Name the areas in a woody stem through which respiratory exchange of gases takes place.

Q 42.

Out of photosynthesis and respiration in plants, which process occurs :
(a) all the time ?
(b) only at daytime ?

Q 43.

Name an animal which absorbs oxygen through its moist skin.

Q 44.

Where does the blood absorb oxygen in the human body ?

Q 45.

Name the red pigment which carries oxygen in blood.

Q 46.

Which gases are exchanged in your lungs ?

Q 47.

Fill in the following blanks with suitable words :
(a) The organs of respiration in man are the…………..
(b) The actual exchange of gases takes place in the………… of the lungs.
(c) ………………in the lungs provide a very large surface area for gaseous exchange.
(d) Yeast undergoes……….. respiration whereas Amoeba undergoes………….. respiration.
(e) Gills are the breathing organs in…………..

Q 48.

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

Q 49.

How does amoeba engulf its food?

Q 50.

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