Circulatory System Flashcards

Flashcards reviewing the circulatory system, blood, and the heart.

Cardiac System Function

Transports nutrients and gases around the body. Transports waste to the lungs and kidneys for removal.

Major Organs of the Cardiac System

Blood, Blood Vessels (Arteries, Veins, Capillaries), Heart

Average adult blood volume

Approximately 5 liters.

Blood viscosity

About 3x more viscous (thicker) than water.

Normal blood pH range

7.35 to 7.45.

Blood Transports

Oxygen, nutrients, waste, and hormones.

Blood Regulates

Body temperature, pH, and fluid volume.

Blood Prevents

Infection and blood loss.

Composition of Blood

55% plasma, 1% white blood cells and platelets, 44% red blood cells.

Plasma Composition

90% water, 10% dissolved gases, salts, minerals, nutrients, enzymes, hormones, waste, and proteins.

Albumin

Regulates osmosis between blood and tissues.

Globulins

Transport substances or fight infection.

Fibrinogen

Used in blood clotting.

3 Formed Elements

Erythrocytes, Leukocytes, Platelets

Erythrocytes

Red Blood “Cells”

Erythrocytes Characteristics

About 5 million in each milliliter of blood, produced in red bone marrow, lack nuclei.

Oxygen property in blood

Nonpolar, so it is not soluble in blood.

Erythrocytes get their red color from

Hemoglobin, the oxygen-carrying molecule.

Hemoglobin is

A protein composed of 4 chains - globins.

Globin description

Each globin contains a flat molecule called a heme, which holds an iron atom. Each iron atom can bind to one O2 molecule.

One Hemoglobin Can Hold

4 oxygen molecules.

1 RBC carries how many hemoglobin?

Approximately 270 Million.

Leukocytes

WBCs are called

Job of leukocytes

Protect the body from foreign cells or substances.

Granulocytes

Neutrophils, Basophils, & Eosinophils

Agranulocytes

Lymphocytes & Monocytes

Neutrophils

Engulf and destroy foreign bacteria; most common leukocyte.

Eosinophils

Kill parasitic worms ingested in food; active during allergic reactions.

Basophils

Release histamines, which dilate blood vessels so other leukocytes can rush to an infection or allergen.

3 types of lymphocytes

T-cells, B-cells, NK Cells.

Macrophages

Attack and engulf viruses, parasites, and bacterial infections.

Thrombocytes

Platelets

Platelets Description

Lack a nucleus and are much smaller than red blood cells, made of tiny fragments of other cells.

Platelets are responsible for

Clotting in the blood.

When a blood vessel is injured, the epithelial tissue releases

Thromboplastin, a chemical that makes the platelets stick to the opening, plugging the hole.

Formation of a blood clot

Coagulation

Coagulation is important for

Restricting blood loss after a cut or bruise.

Hemostasis

The stopping or slowing down of blood flow.

An abnormal clot forms within a blood vessel

A thrombus.

Thrombus dislodges and floats through the blood

An embolus.

Blood types are

Determined by the presence of antigens on red blood cells.

Type A has

A antigens.

Type B has

B antigens.

Type AB has

Both A and B antigens.

Type O has

Neither A nor B antigens.

Blood types produce antibodies that

Attack foreign blood cells. They do not produce antibodies for antigens they already have.

The presence of antibodies in the blood

Makes blood typing essential before a blood transfusion.

Universal Donor

O

Universal Recipient

AB

Rh Factor (Rhesus Factor)

An inherited protein that is found on the surface of RBCs.

Taking into account Rh factor

O - is the Ultimate Universal donor. AB + is the Ultimate Universal receiver.

2 loops that circulate blood back to the heart

Pulmonary Circuit and Systemic Circuit

Pulmonary Circuit

Carries blood from the heart to the lungs and back. Picks up O2 and releases CO2.

Systemic Circuit

Carries blood from the heart to the body tissues and back. Drops off O2 and picks up CO2.

3 types of blood vessels

Arteries, Veins, Capillaries

Arteries

Carry blood away from the heart.

Veins

Carry blood towards the heart.

Capillaries

Connect arteries to veins and are responsible for exchanging gases with the body tissues (thinnest blood vessels)

Blood vessels Functions

Transport O2 and nutrients to the body’s tissues, Transport CO2 and other waste away from the body’s tissues, Help regulate blood pressure.

Arteries have

Thick, muscular walls.

Veins have

Thinner walls and often valves to prevent backwards blood flow.

the heart is

Located between the lungs.

Contracts

About 72 times per minute.

The surface of the heart is covered with a protective layer of tissue called

The epicardium.

Pericardium function

To reduce friction from surrounding organs during pumping.

Epicardium

Outer layer.

Myocardium

Middle layer.

Endocardium

Inner layer.

2 atria

Right Atrium, Left Atrium

2 Ventricles

Right Ventricle, Left Ventricle

Valves

Flaps of tissue that prevent blood from flowing backwards

Atrioventricular (AV) valves

Right side- tricuspid valve (3 flaps of tissue), Left side- bicuspid valve/mitral valve (2 flaps of tissue)

Semilunar valves

Right side- pulmonary valve, Left side- aortic valve

Deoxygenated blood flow from body tissues

superior vena cava and inferior vena cava -> right atrium -> right ventricle -> pulmonary arteries -> lungs

Oxygenated blood

pulmonary veins à left atrium à left ventricle à aorta

Heartbeat components

Systole = contraction of heart, Diastole = relaxation of heart & filling with blood

Heartbeat begins at

The sinoatrial (SA) node.

The SA node begins the impulse, which causes the contraction of the atria. Next, the impulse pauses

0.1 sec to the atrioventricular node (AV node)

The SA node is also called the

Natural cardiac pacemaker.

Purkinje Fibers

Extensions of the Bundle of His that are located in inferior aspect of the ventricles

Purkinje Fibers allows for the electrical impulse

To stimulate the inferior aspect of the Ventricles, causing the depolarization and contraction of the ventricles in an inferior to superior direction

Alternate name for heartbeat

Cardiac Cycle

5 pulse locations

Brachial Artery, Carotid Artery, Radial Artery, Femoral Artery, Dorsalis Pedis Artery

Normal pulse range for Adults

60 to 100 bpm.

Most common artery to palpate?

Radial Artery

Target Heart Rate During Exercise

Calculate: Maximum HR (220 bpm – your age) x Target Exercise intensity (50 to 85%)

Max HR

220 bpm – your age.

Your blood pressure is recorded as two numbers:

Systolic blood pressure (the first number) and Diastolic blood pressure (the second number)

Systolic blood pressure

Indicates how much pressure your blood is exerting against your artery walls when the heart beats.

Diastolic blood pressure

Indicates how much pressure your blood is exerting against your artery walls while the heart is resting between beats.