cardiovascular system lecture

Arteries

Carry blood away from the heart

Capillaries

Site of exchange and diffusion

Veins

Return blood to the heart

Blood functions

Transports gases nutrients hormones and wastes assists temperature regulation aids defense against disease

Average blood volume male

Five to six liters

Average blood volume female

Four to five liters

Blood pH

Seven point three five to seven point four five

Red blood cells erythrocytes

Carry oxygen and carbon dioxide rich in hemoglobin lack nucleus ER and mitochondria

Source of deoxygenated blood

Body tissues

B lymphocytes function

Produce antibodies

T lymphocytes function

Regulate immune response

Erythropoietin

Kidney hormone released during low oxygen that stimulates red blood cell production in red bone marrow

Atrioventricular valves

Bicuspid valve and tricuspid valve

Reason blood does not flow backward in heart

Valves ensure one way flow

Semilunar valves

Aortic valve and pulmonary valve

Cardiac muscle gap junctions

Allow ions and electrical signals to pass directly between cells

Cardiac output

Amount of blood pumped by left ventricle per minute

Cardiac output depends on

Heart rate and stroke volume

Cause of plateau phase

Calcium enters while sodium exits

Absolute refractory period

Ensures cardiac muscle relaxation before next contraction

Tunica intima

Innermost vessel layer made of endothelial cells

Tunica media

Middle vessel layer made of smooth muscle cells

Tunica externa

Outer vessel layer made of fibroblasts

Tunica externa arteries vs veins

Not bigger in arteries

Tunica externa vs tunica media in veins

Tunica externa is thicker

Elastic arteries

Large arteries near heart including aorta and pulmonary trunk

Tetanus in cardiac muscle

Yes

Endothelial cells complete lining

True

Fenestrated capillaries

Porous capillaries for filtration in kidneys

Sinusoid capillaries

Large gaps allow passage of large molecules

Arteriosclerosis

Hardening and loss of elasticity of arteries

Myocardial infarction

Heart attack caused by blocked coronary blood flow

Each of the following is a way that blood transports materials around the body except A) nutrients from the digestive tract to the body B) hormones from endocrine glands to target cells C) carbon dioxide from the lungs to the tissues D) wastes from the cells to the kidneys

Carbon dioxide from the lungs to the tissues

The combination of plasma and formed elements is called A) serum B) lymph C) whole blood D) extracellular fluid

Whole blood

The percent fraction of formed elements relative to whole blood is the A) hematocrit B) specific gravity C) viscosity

Hematocrit

Platelets are A) red cells that lack a nucleus B) blue cells that have a nucleus C) cytoplasmic fragments of large cells D) tiny cells with a polynucleus

Cytoplasmic fragments of large cells

Which of these is not one of the formed elements of blood A) RBCs B) platelets C) antibodies D) lymphocytes

Antibodies

The superior portion of the heart where major blood vessels enter and exit is the A) base B) apex C) right border D) left border

Base

Intercalated discs between cardiac muscle cells serve to transfer from cell to cell A) ionic currents B) action potentials C) the force of contraction D) all of the answers are correct

All of the answers are correct

Blood is supplied to the myocardium by A) the coronary arteries B) contact with blood in the pumping chambers C) arteries that branch from the pulmonary arteries D) none of the answers are correct

The coronary arteries

Blood returning to the heart from the pulmonary circuit first enters the A) right atrium B) right ventricle C) left atrium D) left ventricle

Left atrium

The right ventricle pumps blood to the A) right and left lungs B) left ventricle C) left atrium D) aorta

Right and left lungs

In cardiac muscle the fast depolarization phase of the action potential is the result of membrane permeability to ions A) increased sodium B) increased potassium C) decreased calcium

Increased membrane permeability to sodium

The long plateau phase of the cardiac muscle action potential is due to A) movement of fewer sodium ions into the cell B) calcium channels remaining open C) decrease in calcium diffusion across the membrane

Calcium channels remaining open

The has a greater workload than the A) left ventricle right ventricle B) right ventricle left ventricle

Left ventricle has a greater workload than the right ventricle

The inferior point of the heart is called the A) base B) apex C) right border D) left border

Apex

Conducting system sequence 1 Purkinje fibers 2 AV node 3 SA node 4 bundle branches A) 1 3 2 4 B) 2 3 4 1 C) 2 4 3 1 D) 3 2 4 1

SA node AV node bundle branches Purkinje fibers

Arrange the structures in order blood will encounter them from the heart back to the heart 1 venules 2 arterioles 3 capillaries 4 elastic arteries 5 medium veins 6 large veins 7 muscular arteries A) 4 7 2 3 1 5 6 B) 6 5 1 3 2 7 4 C) 5 6 1 3 2 7 4 D) 2 7 6 3 1 5 4

Elastic arteries muscular arteries arterioles capillaries venules medium veins large veins

Which of the following are the smallest venous vessels A) large veins B) venules C) medium veins D) capillaries

Venules

Which of the following is the innermost layer of a blood vessel A) tunica intima B) external elastic membrane C) tunica media D) tunica externa

Tunica intima

Exchange substances between blood and tissues happens in arteries veins or capillaries

Capillaries

Capillaries with a perforated lining are called A) continuous capillaries B) fenestrated capillaries C) sinusoidal capillaries D) sinusoids

Fenestrated capillaries