Q9 of 805 Page 1

Why are certain group of bacteria referred to as methanogens? List any two characteristic features of methanogens.

Certain group of bacteria are referred to as methanogens as they produce methane gas as a metabolic by-product in hypoxic environment.

Two characteristics of methanogens are:

a) These are strictly unicellular anaerobes.

b) They are extremophiles and can survive in extremes of conditions.

c) They produce methane gas as metabolic by-product.

A few examples of methanogens are: Methanosaeta concilii and Methanopyrus kandleri.

How are different varieties of pollen grains stored for long period of time in pollen banks?

Differentiate between monoecious and dioecious plants. Give one example of each.

(a) Draw a diagram of a sectional view of a monocot seed (grain).

(b) Label and write the functions of coleoptile, coleorhiza, endosperm.

Explain the following with reference to drug/alcohol abuse:

(a) Addiction

(b) Dependence and