Cardiovascular System – Unit 4 Review

Fill-in-the-blank flashcards covering core terminology, mechanisms, and regulatory principles of the cardiovascular system, blood physiology, and haemostasis from Unit 4 notes.

The cardiovascular system transports materials through the body by __ rather than diffusion.

bulk flow

__ is the major material transported because many cells absolutely require it to survive.

Oxygen

Interrupting blood flow to the brain for 5–10 seconds causes __.

loss of consciousness

The heart has __ pumps in series to overcome pressure drops across capillary beds.

two

The tough membranous sac surrounding the heart is called the __.

pericardium

Inflammation of the pericardium is known as __.

pericarditis

Specialized autorhythmic cells located in the right atrium form the __ node.

sinoatrial (SA)

Pacemaker cells drift upward from a starting membrane potential of about __ mV.

–60

“Funny” (If) channels are permeable to both and ions.

Na⁺; K⁺

During early pacemaker depolarization, net __ influx predominates.

Na⁺

Sympathetic stimulation releases __ that binds to β₁-adrenergic receptors to speed the heart.

norepinephrine (or epinephrine)

Parasympathetic stimulation slows the heart via release of __.

acetylcholine

Action potentials spread between cardiac cells through low-resistance connections called __.

gap junctions

The pathway connecting the SA node to the AV node is the __ pathway.

internodal

Impulses leave the AV node through the __ of His.

bundle

Right and left bundle branches terminate as __ fibres in the ventricular walls.

Purkinje

On an ECG, the __ wave represents atrial depolarization.

P

On an ECG, the __ complex corresponds to ventricular depolarization.

QRS

The "lub" heart sound is produced by closure of the __ valves.

atrioventricular (AV)

Stroke volume equals end-diastolic volume minus __.

end-systolic volume

Cardiac output equals heart rate multiplied by __.

stroke volume

According to the Frank-Starling law, increasing __ increases stroke volume.

end-diastolic volume (EDV)

Flow of blood is directly proportional to the __ gradient.

pressure

Vascular __ is the vessel characteristic that most strongly affects resistance.

radius

Mean arterial pressure ≈ diastolic pressure + __ of pulse pressure.

one third

Baroreceptors located in the carotid arteries and the __ monitor arterial pressure.

aorta

An increase in blood pressure causes baroreceptors to fire more and __ sympathetic output.

decrease

Parasympathetic fibres reach the heart mainly through the __ nerve.

vagus

Blood pressure is commonly measured with a device called a __.

sphygmomanometer

The formation of red blood cells is called __.

erythropoiesis

The kidney-derived hormone __ stimulates red blood cell production.

erythropoietin (EPO)

Haemoglobin consists of four protein __, each surrounding a heme group.

globin chains

Approximately __ % of the body's iron is contained in haemoglobin.

70

Platelets are fragments of large bone-marrow cells called __.

megakaryocytes

Production of platelets is regulated by the cytokine __.

thrombopoietin (TPO)

White blood cell formation (leukopoiesis) is stimulated by __-stimulating factors.

colony

Haemostasis involves vascular spasm, platelet plug formation, and __.

blood clotting (coagulation)

In the intrinsic coagulation pathway, exposure to collagen activates factor __.

XII

Thrombin converts fibrinogen into insoluble __.

fibrin

Fibrin strands are cross-linked by activated factor __.

XIII

Breakdown of a clot is called __.

fibrinolysis

The enzyme that digests fibrin during clot removal is __.

plasmin

According to the flow equation, Flow ∝ ΔP divided by __.

resistance

Circulating epinephrine binding to β₂ receptors in certain vessels causes __.

vasodilation

A resting heart rate below 60 bpm is termed __.

bradycardia

A resting heart rate above 100 bpm is termed __.

tachycardia

High blood pressure can result from increased cardiac output, blood volume, or elevated __ resistance.

peripheral

The minimum ventricular volume at the end of contraction is the __.

end-systolic volume (ESV)

The unstable rising membrane potential of pacemaker cells is called the __ potential.

pacemaker

Pressure generated during ventricular contraction is known as __ pressure.

systolic

Specialized junctions between cardiac muscle cells containing desmosomes and gap junctions are called __.

intercalated discs

A clot that forms and remains in an intact blood vessel is a __.

thrombus