Question

What are the adaptations which make the fish move in water?

Answer 1

Hint: The process of evolution has evolved various new characters in fishes that help them to adapt to the movement in the water. These adaptations include the presence of gills, fins, and swim bladders for their movement and locomotion.

Complete answer:
- Fishes have gills for respiration and lack limbs with digits. They do not need to produce as they can with their heightened sense organs will be able to detect the other organisms and can share signals with one another for the purpose of feeding, courtship behavior, and aggression.
- Fishes constitute swim bladders which help them in maintaining body weight and buoyancy in the water and help in swimming.
- They have a streamlined body which helps them to swim in the water bodies with ease.
- Fishes are ammonotelic i.e they secrete ammonia as the main excretory product. Urea, uric acid, and ammonia are the nitrogenous waste substances that are produced during the process of nucleic acid and protein metabolism. The most toxic nitrogenous wastes are found to be Ammonia. To remove or excrete ammonia from the body, organisms require a large amount of water first to make it dilute.
- To maintain their water balance the kidneys are adapted to excrete large amounts of dilute urine. The glomerulus and capillaries are large and well developed for the process of filtration of the blood which later produces urine.
- The skin, mouth, and gills are responsible for the transfer of salts within the body and outside the body to maintain osmoregulation.
- The water enters constantly through the gills and the mouth.
- By the process of diffusion their body loses salts. This helps in the maintenance of osmoregulation as the special gill cells are evolved that help in the transportation of salts from the salty water to the body.
- The gills need mitochondria-rich cells to perform their function of salt uptake.

Note:
The fishes have highly sensitive sense organs that can detect their prey even from a mile. It is observed that their body is colored to the background of their surrounding so that they can blend within their surrounding and help in the process of camouflage.