lab 7

cardiovascular system anatomy

what is the difference between atria (atrium) and ventricles?

atria: upper chambers of the heart, receive blood, right atrium receives blood from the superior and inferior vena cava, left atrium receives blood from the pulmonary veins

ventricles: lower chambers of the heart, pumps blood out of the heart, right ventricle sends blood to the pulmonary trunk and pulmonary arteries, left ventricle sends blood to the aorta

what is the flow of a red blood cell? (pathway of blood through the heart)

right atrium, tricuspid valve, right ventricle, pulmonary valve, pulmonary artery, lungs, pulmonary veins, left atrium, mitral valve, left ventricle, aortic valve, aorta

why is it important for arteries to be elastic and contractible?

elasticity: allows arteries to stretch when the heart pumps and maintains blood flow

recoil: pushes blood forward even when the heart relaxes

contractility: smooth muscle controls blood pressure and blood flow (vasoconstriction/vasodilation)

describe blood flow to the right ankle and back to the heart

to ankle: aortic arch, descending aorta, abdominal aorta, common iliac artery, external iliac artery, femoral artery, smaller arteries, capillaries

back to heart: capillaries, venules, veins, femoral vein, external iliac vein, common iliac vein, inferior vena cava, right atrium

how does blood return from the body back to the heart? (the mechanisms)

• skeletal muscle pump (muscle contraction pushes blood)

• valves in veins (prevents backflow)

• breathing movements (help pull blood upwards)

why should you cool down after exercise?

• prevents blood pooling in the legs

• prevents dizziness and fainting

• maintains blood pressure

where is the heart located?

• behind the sternum

• in the mediastinum (between lungs)

• slightly left of midline

• located in the thoracic cavity

why is the left ventricle wall thicker?

• pumps blood to the entire body under high pressure

• right ventricle only pumps blood to the lungs under low pressure

• needs more muscle so it has a thicker wall

why are heart valves so important?

• ensures one-way flow

• prevents backflow

what would happen if your heart had leaky valves?

• heart can still function, but less efficiently

• can lead to heart enlargement, fatigue, or failure