Their shells protect them against predators and rough elements. Crabs have tight grips with their pincers, which allows them to grab hold of predators and fend them off. ... Their ability to condense their bodes enables crabs to take cover under rocks and other objects to hide from predators.
A hard outer shell offers protection against predators, in addition to the crab's claws, which they use to hunt prey or fight off predators.
Answer:
The correct answer will be option-A
Explanation:
The sympathetic nervous system is a type of the autonomic nervous system which mediates the homeostasis and stress response.
During stress condition, it initiates the hormonal response called fight or flight response by secreting acetylcholine from the adrenal medulla which stimulates the secretion of the epinephrine and norepinephrine.
This hormone produces an observable response like increase in the heart rate, widening of the bronchial passages, constriction of the blood vessels, pupillary dilation, perspiration and <em>decreases motility of the large intestine.
</em>
Thus, option-A is the correct answer.
<span>The metabolic activity of a specific region of the living rat brain can be revealed by measurement of Fos protein concentration.
c-Fos is a proto-oncogene that is the homolog of the retroviral oncogene v-fos. It was first discovered in rat fibroblasts as the transforming gene of the FBJ MSV.</span>
