What kinds of valves are found in the human circulatory system and how do they differ?

The three main kinds of valves in the human circulatory system are atrioventricular valves, semi-lunar valves and pocket valves. Atrioventricular valves are found in the heart and separate the atria and ventricles. During ventricular systole (contraction), the pressure is higher in the ventricles compared to the atria, so AV valves prevent back-flow of blood into the atria. Semi-lunar valves are found in the aorta and pulmonary artery. During diastole, the ventricular walls relax and the elastic walls of the vessels recoil, so the pressure is higher in the vessels and semi-lunar valves prevent back-flow into the ventricles. Pocket valves are found in veins throughout the venous system. They ensure one-way flow of blood towards the heart.

Answered by Elanor B. Biology tutor

4097 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

What's the difference between allopatric and sympatric speciation? What are some evolutionary implications of this?


Briefly describe how the autonomic nervous system returns internal body temperature to normal following a rise in body temperature


What's the difference between genetic code, genetic material and genetic information?


How are enzymes inhibited?


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