The main difference between human respiration and fish respiration is that humans breathe air through their lungs, while fish breathe water through their gills.
Humans and fish breathe in a very similar way. We both take in oxygen. The oxygen is taken in and circulated.
But while humans are air-breathers, fish are water-breathers. So how exactly do fish breathe? Let us find out how these cold-blooded vertebrates breathe under water.
Why Do Fish Need Oxygen In Water?
Fish need to breathe in order to live. They take in oxygen through their gills, which allows them to use their aerobic respiration system and generate energy, allowing them to swim, hunt for food, and survive.
Without oxygen, fish would not be able to move around or survive for very long at all. Fish breathe to live. They take in oxygen and release carbon dioxide, just like humans do.
How Do Fish Breathe?
Fish use their gills to breathe, which is how they extract oxygen from the water. The gills are a special organ that contains thin filaments covered in blood vessels.
When water flows over these filaments, dissolved oxygen is absorbed from the water into the bloodstream of fish. At the same time carbon di-oxide is let out.
Fish have a heart that pumps blood through their bodies. The blood also carries nutrients around the fish’s body, allowing it to grow and develop normally.
What Are Gills?
Gills are a respiratory organ that help fish breathe. The gills’ feathery filaments are rich in blood vessels, so they are able to exchange oxygen and carbon dioxide efficiently.
They contain blood vessels, capillaries and lamellae. The lamellae are fleshy flaps that contain many blood capillaries.
Their purpose is to extract oxygen from water through a process called diffusion—the movement of molecules from an area of higher concentration to an area of lower concentration across a barrier (often a membrane). This is called osmosis.
Fish also have swim bladders, which are internal organs that help them stay buoyant in the water.
What Is The Structure Of The Gills?
The gills of fish are a structure made up of filaments, which are covered by lamellae. The lamellae are thin, plate-like structures that cover the filaments.
In between the filaments and lamellae is a capillary blood network that absorbs oxygen from the water. The lamellae are in layers, which allows for maximum surface area for diffusion of oxygen into the capillaries.
The protein molecules found inside the lamellae maximize the amount of oxygen extracted from water.
The purpose of the lamellae is to maximize the amount of oxygen extracted from water by maximizing the surface area through which the oxygen diffuses into capillaries.
The protein molecules in these structures are optimized to maximize this diffusion.
What Functions Do The Gills Perform?
The gills perform a number of functions, including:
1. Oxygen is absorbed by the blood in the capillaries that line the gills.
2. Carbon dioxide is expelled from the body through diffusion across the thin membrane that separates each gill and its associated blood vessel.
3. 75% of ammonia is excreted through gills. The remaining ammonia is excreted through the excretory system.
4. Osmoregulation: The osmoregulation process balances the amount of salt in your fish’s environment with how much salt is already in their tissues. A healthy fish has a stable balance between these two factors, (salts and minerals) but if something upsets this balance it can cause problems for the fish’s health and well-being.
5. Filter dirt from entering: As water flows over the surface of the fish’s gills, small debris such or algae may pass. The gills perform the function of ensuring that these do not enter the body or blood stream.
What Is Osmoregulation?
Osmoregulation is the process of regulation of electrolytes and water pressure within fish.
There are two main types of osmoregulation: passive and active.
In passive osmoregulation, the body maintains a constant internal environment by preventing water loss and retaining salt, even when external conditions change.
In active osmoregulation, the body actively regulates its internal fluid balance by changing its osmotic pressure or using special mechanisms to remove salts from its blood stream.
Did You Know?
Breathing is harder for fish: Breathing is harder in fish because oxygen percentage in water is higher than air.
Fish must take in a greater amount of water with each breath than humans do to get the same amount of oxygen. This is because water and air have different densities, so the amount of oxygen that can be stored in a given volume of each substance is different.
Skin On The Gills Is Thin:
A thin skin on the gills of fish is a necessary adaptation to increase the surface area of the gills, which allows fish to breathe. The greater the surface area of the gills, the more oxygen can be taken in and released from water into the blood stream. This is especially important for larger fish, since they require more oxygen than smaller ones.
Blood passes in the opposite direction of the water in fish:
The blood passing through the gills is going in the opposite direction of the water. This happens to ensure that the water passes through, and the oxygen is absorbed more effectively than if the reverse is happening.
Some fish breathe through their skin also:
When it comes to breathing, fish have a few different options. For example, some fish breathe through their gills, which are located on both sides of the head. However, some fish don’t develop gills until they are older. These fish have an option to breathe through their skin instead of their gills while they wait for their gills to develop.
There you have it, a short overview of how fish breathe.
Gills are one of the most remarkable organs in the animal kingdom, and they are truly fascinating. Have you ever wondered how it feels to breathe underwater? Perhaps you’ve been wondering how they work! Well, now you know!
It’s important to remember that each fish species has their own unique adaptations that allow them to make use of the environment around them.