Class Notes (835,868)
United States (324,281)
Biology (713)
CAS BI 106 (88)
Lecture 23

CAS BI 106 Lecture 23: Anatomy Lecture 23

2 Pages
Unlock Document

CAS BI 106
Dale Pasino

Lecture 23 4517 Atherosclerosis Atherosclerosis: a progressive hardening and blocking of the arteries Arteries are blocked by plaques that develop in early adulthood and progressively get larger The individual does not know they have plagues until they get really big Who gets it: o More males than females o Those with high cholesterol o Those with high blood pressure o Smokers Minor damage to vessel wall Patch with cholesterol until healed If too much cholesterol in blood, more will stick to wound Builds up over time Begins in 20s Conduction system Remember that cardiac muscle cells have a special feature: intercalated discs o Tie the cardiac muscle cells together physically o And contain gap junctions that allow electrical signals to pass through o Therefore muscle impulses can pass from one cell to the next instantly o Cardiac muscle is forked. A signal received on one end is passed onto two cells o Desmosomes are there to keep cell membranes together and let particles flow from one cell to another . A mixture of gap junctions and desmosomes are called intercalated discs Heart beats Heart autorhythmicity (heart itself, not external nerves initiates muscle impulses) o Your heart would continue to beat if you cut the cord that connects the heart and the brain Specialized heart muscle cells initiate muscle impulses, the rest of the muscle cells just pass along the impulse The initiation cells make up the conduction system o The conduction system is a network of fibers within the heart that generate the initial impulse and spread it throughout the tissues of the heart. That signal can then pass through the gap junctions The conduction system cells initiate electric muscle impulses that travel throughout the cardiac muscle tissue by way of the intercalated discs Muscle impulses are started at the (wall of the right atria) sinoatrial (SA) node in the posterior of the right atrial (pacemaker) The impulse is carried to a mode at the inferior border of the right atria called the atrioventricular (AV) node The impulse is carried from this node down a bundle called the bundle of His, the branches of this bundle, called purkinje fibers, carry the impulse throughout the walls of the ventricles Cardiac Arrhythmias
More Less

Related notes for CAS BI 106

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.