Explain what is meant by counter current exchange in fish? Describe how it works and what adaptations the gills have to assist it.

Counter current exchange is the mechanism in which oxygen enters the blood in fish. Blood flows in the opposite direction to the water that flows over the fish's gills. Fish gills have gill filaments and these filaments have protrusions called lamellae which the water flows over. The lamellae increase the surface area of the gills meaning that there is a larger area for the oxygen to diffuse over. With the counter current exchange system the water is always richer in oxygen than in the blood therefore maintaining the concentration gradient. The oxygen then diffuses into the blood capillaries of the fish.

KF
Answered by Katie F. Biology tutor

58256 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

Describe how negative feedback is used to control blood glucose concentration


An extract of DNA contains 4000 base pairs. The extract is identified to contain 300 guanine bases. How many adenine bases can be found in the DNA extract?.


How does does changing the pH affect the activity of an enzyme?


What is the basic biochemistry of carbohydrates?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences