Describe the control of heart rate

1.) First starts in the sino-atrial node. 2.) Sino-atrial node sends out regular waves of electricity to the atrial walls in order to initiate heart beat.3.) This leads to contraction of right and left atria.4.) A non-conducting band of collagen stops the electrical waves passing straight to the ventricles.5.) Some of these waves reach the atrioventricular node (AVN). This then passes waves of electricity down the bundle of His.6.) However, there is a delay before the AVN sends out its activity in order to allow the atria to fully empty. After the delay, the electrical waves pass down the bundle of His.7.)Bundle of His splits into thinner fibres splitting left and right. These are the Purkinje fibres.8.) The Purkinje fibres carry the electrical waves into muscular walls of the two ventricles leading them to contract simultaneously from the bottom up.

Answered by Cian T. Biology tutor

836 Views

See similar Biology A Level tutors
Illustration of a video tutorial

Need help with Biology?

One to one online tuition can be a great way to brush up on your Biology knowledge.

Have a Free Meeting with one of our hand picked tutors from the UK’s top universities

Find a tutor

Related Biology A Level answers

All answers ▸

What is the difference between the leading and the lagging strand in DNA replication?


Frequent treatment with antibiotics can result in resistant strains of bacteria, explain how.


What is a mutation and what are they caused by?


Explain the process of transcription in living cells


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 2013–2022

Terms & Conditions|Privacy Policy