Question

The yellow tang is a marine fish with lesser salt content in their bodies than the seawater. Thus fluid could be drained out of the body into the sea due to difference in salinity. This could be dangerous and fatal to the organism. How do they manage to survive in such conditions?

• A. The respiration rate increases.
• B. They accumulate more salts in their body.
• C. They excrete large amounts of water.
• D. They drink large amounts of water.

Answer 1

The correct option is D They drink large amounts of water.

$\bullet$ Marine animals maintain a constant internal salt concentration which helps them survive in a hypertonic environment (seawater).
$\bullet$ Marine organisms tend to dehydrate as water is lost by osmosis and hence they consume excess water to maintain their body's osmolarity.
$\bullet$ These organisms have organs like kidneys and gills, which help them secrete excess saltwater out of their bodies.