Chapter 13 - Blood, Heart, and Circulation - Chapter 13

These flashcards cover key terms and concepts from Chapter 13 on Blood, Heart, and Circulation.

Circulatory System

Organ system that transports molecules and other substances rapidly over long distances, between cells, tissues, and organs.

Cardiovascular System

Includes the heart (pump) and blood vessels (pipes) in the circulatory system.

Plasma

The fluid portion of blood that includes water, ions, proteins, nutrients, gases, hormones, and wastes.

Hematocrit

Rapid assessment of blood composition, indicating the percent of blood volume that is composed of red blood cells.

Hemoglobin

Protein in red blood cells that carries oxygen to tissues and carbon dioxide away from tissues.

Atria

Chambers of the heart that receive venous blood returning to the heart.

Ventricles

Chambers of the heart that pump blood into arteries.

Pulmonary Circulation

The circuit through which partially oxygenated blood travels from the right ventricle to the lungs and back to the left atrium.

Systemic Circulation

The circuit through which oxygenated blood travels from the left ventricle through the organ systems.

AV Valves

Valves located between atria and ventricles; include tricuspid and bicuspid (mitral) valves.

Cardiac Cycle

The alternating contractions and relaxations of the atria and ventricles; consists of systole (contraction) and diastole (relaxation).

Heart Sounds

The sounds produced by the closure of heart valves; 'lub' is the first sound (AV valve closure) and 'dub' is the second sound (SL valve closure).

Electrocardiogram (ECG)

A test that detects electrical activity in the heart and records the electrical impulses as waves.

Capillaries

Smallest blood vessels that mediate the exchange of substances between blood and interstitial fluid.

Atherosclerosis

A condition characterized by the thickening of arterial walls with plaques that include cholesterol and fat deposits. (buildup of plaques. narrows arteries, reducing blood flow)

Lymphatic System

System that transports excess interstitial fluid back to the blood and defends against disease-causing agents.

Right Ventricle (RV)

Pumps blood to the lungs through pulmonary arteries

Left Ventricle (LV)

Pumps oxygenated blood to the rest of the body (tissues+organs) through the aorta

Pulmonary Circulation

What circulation does the RV go through?

Systemic Circulation

What circulation does the LV go through?

Interventricular Septum

Divides the 2 ventricles

Right Atrium

Receives oxygen-poor blood from the body and the blood comes through the vena cava

Left Atrium

Receives oxygen-rich blood from the lungs and blood comes through the pulmonary veins

Fibrous Skeleton

Separates the atria and ventricles - It helps keep the structure strong and keeps the electrical signals flowing in the right direction.

Tricuspid and Bicuspid valves

The 2 AV Valves

Tricuspid Valve

Valve in between right atrium and right ventricle

Bicuspid Valve

Valve in between left atrium and left ventricle

Pulmonary and aortic valves

2 Semilunar Valves

Pulmonary Valve

Valve between the left ventricle and pulmonary trunk (leads to the lungs)

Aortic Valve

Valve between right ventricle and aorta (leads to the rest of the body)

0.8 seconds

The duration of alternating contractions and relaxations of atria and ventricles.

Systole

When the ventricles contract. This pushes blood out of the heart and heart pressure increases.

Diastole

When the ventricles relax. This allows them to fill with blood and heart pressure drops.

0.3 seconds

Systole duration

0.5 seconds

Diastole duration

AV valve (atrioventricular valve)

What valve closes during “lub”?

SL valve (semilunar valve)

What valve closes during “dub”?

Isovolumetric contraction

When pressure in ventricles increases as ventricles begin contraction, causing AV valves to close

120 mm Hg

Systolic blood pressure

Stroke volume

The amount of blood pumped out. Around 2/3 of the blood in the ventricles.

80 mm Hg

Diastolic blood pressure

End-diastolic volume

Amount of blood in the ventricles at the end of diastole

SA Node

Pacemaker of the heart

Bundle of His

Carries the signal from the AV node to the ventricles. This causes the ventricles to contract after the atria

P wave

Results from the spread of atrial depolarization.

QRS wave

Results from spread of depolarization into the ventricles.

T wave

Results from repolarization of the ventricles.

connective tissue, epithelial tissue, smooth muscle

Blood vessels are made of

Arteries

Carry blood away from the heart

Veins

Carry blood back to the heart

Arteries (characteristic)

Have strong, thick, elastic walls that resist flow. → High Pressure/Low Volume

Veins (characteristic)

Have weaker walls and a wider lumen and fill

more easily. → Low Pressure/High Volume

Arterioles

Small arteries where the biggest drop in blood pressure happens. Control how much blood flows into the capillaries

Vasoconstriction

Narrowing the vessel by tightening muscles → less blood flows

Vasodilation

Widening the vessel by relaxing muscles → more blood flows

Capillaries

Smallest blood vessels in the body. Found in every tissue except the cornea. Made of one thin layer of cells

Skeletal muscle pump

Muscles squeeze veins during movement

One-way venous valves

Keep blood flowing toward the heart

Coronary Artery Disease (CAD)

Less blood flow to the heart (ischemia). This can lead to a heart attack (aka myocardial infarction).

Lymph Nodes

Filter lymph to remove pathogens before the fluid is returned to the blood.