Internal Landmarks - Chambers and Valves

Question 1

Which 3 veins drain into the right atrium?

Answer 1

coronary sinus
SVC
IVC

Question 2

what happens when the AV valve open

Answer 2

A-V valves open and allow blood to flow from atria into ventricles when ventricular pressure is lower than atrial pressure
– occurs when ventricles are relaxed, chordae tendineae are slack and papillary muscles are relaxed

Question 3

what happens when the AV valves close

Answer 3

A-V valves close preventing backflow of blood into atria
– occurs when ventricles contract, pushing valve cusps closed, chordae tendinae are pulled taut and papillary muscles contract to pull cords and prevent cusps from everting

Question 4

what does the skeleton of the heart do

Answer 4

• Separates atria and ventricles
• Provides attachment for muscle fibres
• Supports valves and prevents valves from stretching
• Forms the basis of electrical discontinuity between atria and ventricle