Class Notes (1,100,000)
CA (630,000)
Western (60,000)
PHYSIO (1,000)
Lecture

Physiology 2130 Lecture Notes - Heart Valve, Tricuspid Valve, Aortic Valve


Department
Physiology
Course Code
PHYSIO 2130
Professor
Anita Woods

This preview shows pages 1-3. to view the full 18 pages of the document.
Module 8
Circulatory system I: The Heart
Introduction
Heart sites in your chest cavity between your lungs
The four principle functions of the cardiovascular system are:
o It transports oxygen and nutrients to all the cells of the body
o It transports carbon dioxide and waste from all cells
o It helps maintain body temperature and pH
o It transports and distributed hormones and other substances within the body
Anatomy The heart
The heart essentially consists of two side-by-side pumps:
o The right atrium and ventricle, which pumps blood to the lungs,
o The left atrium and ventricle, which pumps blood to the rest of the body
The wall of the left ventricle is much thicker than the wall of the right ventricle.
o The left ventricle, which delivers blood to the entire body, must contract more forcefully
to propel the blood through the entire systemic circulation.
o The right ventricle, on the other hand, only propels the blood to the nearby lungs and,
therefore, does not need to contract as forcefully.
The valves in the heart, which ensure the one-way flow of blood through the heart, may have
several different names.
o The right atrioventricular (AV) valve is also called the tricuspid valve
o The left atrioventricular (AV) valve is also known as the bicuspid or mitral valve.
Anterior View and Posterior view
Superior vena cava: delivers blood to the heart from the head and upper limbs
Pulmonary artery: blood leaving the right ventricle travels to the lungs through the pulmonary
artery
Aorta: blood leaving the left ventricle travels through the aorta and is distributed to the entire
body

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Right atrium: receives blood from the entire body. This blood is low in oxygen and high in
carbon dioxide. The right atrium will then pump the blood into the right ventricle through the
right atrial-ventricular (AV or tricuspid) valve
Left atrium: receives blood coming from the lungs. This blood is rich in oxygen and low in carbon
dioxide. The left atrium will then pump the blood into the left ventricle through the left atrial-
ventricular (AV or bicuspid) valve
Right ventricle: pumps blood into the pulmonary artery. The pulmonary artery then delivers this
blood to the lungs for gas exchange
Left ventricle: pumps blood into the aorta which then distributed the blood to the entire body
Anterior cutaway
Right AV (tricuspid) valve: ensure that the blood travels in only one direction from the right
atrium to the right ventricle and prevents blood from backing up into the atrium when the
ventricles contract
Left AV (bicuspid) valve: ensures that the blood travels only in one direction from left atrium
to left ventricle and prevents blood from backing up into the atrium when ventricle contract
Pulmonary semilunar valve: ensures that the blood travels in one direction from right
ventricle to pulmonary artery and prevents the blood form backing up into the ventricle when
it relaxes
Aortic semilunar valve: ensures that blood travels only from the left ventricle to aorta and
prevents it from backing up into the left ventricle when it relaxes
Chordae tendineae: are cords of collagen that attach to the valves at one end to papillary
muscles at the other. These structures prevent AV valves from being pushed into the atria when
the pressure in ventricles is high
Papillary muscles: are extensions of the ventricular muscles and are attached to the chordae
tendineae. When the ventricles contract so do the papillary muscles and the AV valves are held
in place and don’t fold backward into the atria

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Circulation through the heart
You're Reading a Preview

Unlock to view full version