• Describe the margins and surfaces of the heart

surfaces include

anterior - sternocostal surface

inferior - diaphragmatic

posterior - Base

apex

• Describe the morphological features of the cardiac valves

atrial ventricular valves -between atrium and ventricles these valve types are more flimsy and contain chordae tendinie (these connect the papillary muscles to the cusps of the atrial ventricular valves these papillary muscles contract just before ventricular contraction which means that the valve wont blow back in on itself into the atrium

include tricuspid - located between the right atrium and ventricle.

mitral valve found between left ventricle and atrium

the difference between mitral and tricuspid is that the mitral valve has 2 cusps but tricuspid has 3

semilunar valves - between ventricles and great vessels do not contain chordae tendinea both are tricuspid

they close due to blood falling back into them (due to gravity) as not all blood can go up the aorta (common misconception is that ALL blood foes out of heart per pump but actually it takes a few pumps)

these valves are much more sustainable