In which parasite do all stages of the life cycle (including the hatching of its eggs) occur on the hide of the host animal?

a. heartworm

b. roundworm

c. lice

d. hookworm

Answer:

The parasite which do all stages of the life cycle (including the hatching of its eggs) occur on the hide of the host animal is (C) Lice.

Explanation:

There are three stages of a lifecycle of a lice: 'egg', 'nymph' and 'adult'. Nits are lice eggs on the head which are confused with dandruff. Egg hatches in around 1 week and release into a nymph. They mature into an adult in 7 days. Adult louse have six legs and can be greyish white in color. They feed on human blood many times in a day.`

For other options like round worms and hookworms, hookworm release eggs and they are released in stool of the dog after few days. This gets mixed in soil and can be consumed by humans as well by exposure. So, these are incorrect options and correct option is lice.

the correct answer is:

a population changes in response to a change in the environment.

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.