Circulation and Respiration Flashcards

This flashcard set covers the anatomy and mechanics of human blood circulation, blood pressure definitions, and the respiratory mechanics of the chest cavity based on lecture diagrams.

Superior and Inferior vena cava

The two veins through which blood returns from the body to the heart.

Right atrium

The heart chamber that receives blood from the Superior and Inferior vena cava.

Tri-cuspid valve

The valve through which blood flows from the Right atrium into the Right ventricle.

Pulmonary arteries

The vessels that carry blood from the heart to the lungs to receive oxygen.

Pulmonary veins

The vessels through which blood travels from the lungs back to the Left atrium of the heart.

Mitral/Bicuspid valves

The valves through which blood moves from the Left atrium into the Left ventricle.

Aortic valve

The valve blood passes through when moving from the Left ventricle into the Aorta.

Aorta

The vessel through which blood flows from the heart to all parts of the body.

Systolic pressure

The pressure in your arteries when the heart has just contracted.

Semilunar valve

A valve that blood passes through when moving to either the Pulmonary Arteries or the Aorta.

Septum

A structural component of the human heart identified for labeling in the heart illustration.

Diaphragm contraction

Represented by Diagram A, this action leads to a decrease in chest cavity pressure as volume increases.

Inhalation

The process represented by Diagram A, occurring when chest cavity pressure decreases.

Exhalation

The process represented by Diagram B, occurring when the rib cage is lowered and chest cavity volume decreases.

Standard lung pressure (Diagram A)

$$760\,mm$$

Condition for air entering the lungs

A state where the pressure inside the lungs is $760\,mm$ and the pressure inside the chest is $754\,mm$.

Exhalation pressure requirement

The pressure behind the push must be greater than the pressure pushing air into the lung in order to push air out.

Diaphragm shapes

The diaphragm can be described in different shapes depending on its contraction or relaxation. During inhalation, it flattens to increase the volume of the chest cavity; during exhalation, it domes up, reducing the volume.

Diaphragm pressure difference

When the diaphragm contracts, it decreases the pressure in the chest cavity relative to the atmospheric pressure, allowing air to flow into the lungs.