Tag: bacteria; benefits and harmful effects

Pili are minute hair like appendages, that emerges from suface of Gram -ve bacteria. They have similar structure as flagella and often involved in attachment to surface and making of biofilm. They also help in DNA exchange. They are involved in conjugation which results in transfer or exchange of genetic material. 

The reproduction in amoeba is asexual, called binary fission, where it replicated its cells by mitosis and its cell divide in two equal daughter cells. Amitosis is similar to binary fission. Meiosis does not take place in amoeba.

The correct answer is B. 

Amoeba takes its food by the method of phagocytosis (i.e ingesting or engulfing the food particles), also by means of pinocytosis (wherein amoeba wraps around its membranes around the food forms vesicles and pinch it inside the membrane and then gradually digests it) and by endocytosis (in which the outermost the membrane of amoeba either stretches inwards or projects outwards to obtain nutrition.

The correct answer is D.

Rhodospirillum bacteria is facultative aerobic Photo - autotrophic bacteria use non-sulphur aliphatic organic  compound as donor of $H _{2}$  go,. Propyl alcohol .

$6CO _{2}+12CH _{3}CHOHCH _{3}\overset{Light}{\rightarrow}$

$C _{6}H _{12}O _{6}+12CH _{3}COH _{3}+6H _{2}O$

In bacteria the site for respiratory activity is found in mesosomes. Mesosomes are folded invaginations in the cell membrane of bacteria. They increases the surface area required for respiration. They contain respiratory enzymes. It is the site of respiratory activity.