ATI TEAS Cardiovascular System

Cardiovascular system

System that circulates blood to transport nutrients, gases, hormones, and wastes

What is the main function of the cardiovascular system?

To move blood throughout the body for nutrient delivery and waste removal

Heart

Muscular organ that pumps blood through the body

Cardiac muscle

Specialized muscle tissue that makes up the heart and allows it to contract

Atria

Upper chambers of the heart that receive blood

Ventricles

Lower chambers of the heart that pump blood out of the heart

How many chambers does the heart have?

Four (two atria and two ventricles)

What is the function of heart valves?

To ensure one-way flow of blood

Arteries

Blood vessels that carry blood away from the heart

Veins

Blood vessels that carry blood toward the heart

Capillaries

Small vessels where exchange of gases and nutrients occurs

Why do arteries have thick walls?

To withstand high pressure from blood pumped by the heart

Why do veins have thinner walls?

Blood pressure is lower and they return blood to the heart

Closed circulatory system

System where blood remains within vessels at all times

Pulmonary circulation

Movement of deoxygenated blood from heart to lungs and back

Systemic circulation

Movement of oxygenated blood from heart to body and back

What happens in pulmonary circulation?

Blood goes to lungs to gain oxygen and release carbon dioxide

What happens in systemic circulation?

Oxygenated blood is delivered to tissues and returns deoxygenated

Systole

Phase when the heart contracts and pumps blood

Diastole

Phase when the heart relaxes and fills with blood

What causes the "lub-dub" sound of the heart?

Closing of heart valves during the cardiac cycle

Sinoatrial node

Natural pacemaker that controls heart rhythm

What is the role of the sinoatrial node?

It sends electrical signals to regulate heartbeat

Plasma

Liquid portion of blood containing nutrients, hormones, and proteins

Red blood cells

Cells that transport oxygen using hemoglobin

Hemoglobin

Protein in red blood cells that binds oxygen

White blood cells

Cells that defend the body against pathogens

Platelets

Cell fragments that help blood clot

What is the function of red blood cells?

To carry oxygen to tissues and carbon dioxide to lungs

What is the function of white blood cells?

To fight infection

What is the function of platelets?

To stop bleeding by forming clots

How is most carbon dioxide transported in blood?

As bicarbonate to help maintain pH balance

Buffer system

System that helps maintain stable blood pH

Lymphatic system

System that drains fluid and supports immune defense

Lymph

Fluid containing immune cells that returns to bloodstream

Lymph nodes

Structures that filter lymph and house immune cells

What is the function of the lymphatic system?

To return fluid to blood and help fight infection

Blood flow cycle

Continuous movement of blood through heart, lungs, and body

Where does oxygenated blood start in the heart?

Left ventricle

What happens after blood leaves the left ventricle?

It travels to the body through arteries

What happens in capillaries of body tissues?

Oxygen is delivered and carbon dioxide is picked up

Where does deoxygenated blood return?

Right atrium

What happens after blood enters the right atrium?

It moves to the right ventricle

What does the right ventricle do?

Pumps blood to the lungs

What happens in the lungs?

Blood gains oxygen and releases carbon dioxide

Where does oxygenated blood return?

Left atrium

Which chamber pumps blood to the lungs?

Right ventricle

Which chamber pumps blood to the body?

Left ventricle

Why are ventricular walls thicker than atrial walls?

They must pump blood with greater force

Which ventricle has the thickest wall and why?

Left ventricle because it pumps blood to the entire body

Atherosclerosis

Buildup of plaque in arteries that restricts blood flow

Hypertension

High blood pressure

Heart attack

Blockage of blood flow to heart muscle

Stroke

Disruption of blood flow to the brain

Aneurysm

Weakening and bulging of a blood vessel

Arrhythmia

Irregular heartbeat

Why is continuous blood flow important?

It ensures oxygen and nutrients reach all cells

How do the respiratory and cardiovascular systems work together?

Lungs oxygenate blood and heart distributes it throughout the body