P-2 Life Processes in Living Organisms Part – 1 — Science STD 10 — Question

P and Q are two types of plants having weak stems which cannot stand upright on their own. The plants P and Q have organs R and S respectively which can grow towards any support which they happen to touch and wind around that support. It is observed that organ R originates from the leaves of the plant whereas organ S originates directly from the stem of the plant.

1. What is (i) R, and (ii) S?
2. What is the name of growth movement exhibited by the organs R and S?
3. Name the stimulus involved in this case.
4. State whether the behaviour of organs R and S is a tropic movement or a nastic movement.
5. Name one plant like P and another plant like Q.

Consider the following chemical reactions which take place in different organisms/ tissues under various conditions:

1. Glucose → Respiration → Respiration Ethanol + Carbon-dioxide + Energy.
2. Glucose → Respiration → Respiration Carbon-dioxide + Water + Energy.
3. Glucose → Respiration → Respiration Lactic acid + Energy.

1. Name one organism which respires according to equation (i) above.
2. Name one organism which respires according to equation (ii) above.
3. When and where does respiration represented by equation (iii) above take place?
4. Which equation/ equations represent aerobic respiration?
5. Which equation/ equations represent anaerobic respiration?
6. Which of the above reactions produces the maximum amount of energy?

Write short note: Blue Revolution.

Describe the working of human blood circulatory system with the help of a suitable diagram which shows all the steps involved.

An element X belongs to group 2 and another element Y belongs to group 15 of the periodic table:

1. What is the number of valence electrons in X?
2. What is the valency of X?
3. What is the number of valence electrons in Y?
4. What is the valency of Y? Explain how you have arrived at your answers.

Which products produced through biotechnology do you use in your daily life?

Mock Drill is useful.

2 The substances formed by specific chemical bond between fatty acids and alcohol are called lipids. Digestion of lipids consumed by us is nothing but their conversion into fatty acids and alcohol. Fatty acids are absorbed and distributed everywhere within the body. From those fatty acids, different cells produce various substances necessary to themselves. Ex. the molecules called phospholipids which are essential for producing plasma membrane are formed from fatty acids. Besides, fatty acids are used for producing hormones like progesterone, estrogen, testosterone, aldosterone, etc. and the covering around the axons of nerve cells. We get 9 Kcal of energy per gram of lipids. Excess of lipids are stored in adipose connective tissue in the body.
Questions and Answers:
(1) Define lipids.
(2) What happens to fats that are eaten in excess?
(3) Which hormones regulating reproductive functions are produced from fatty acids?
(4) How is plasma membrane of the cells formed?
(5) What happens to lipids when their digestion is completed? How much energy do they provide?