things we did not know about the cardiovascular system!

What are the main components of the cardiovascular system?

• Heart, Blood, Lungs

• Heart, Blood, vessels

• Hormones, Vessels, Lungs

• Lungs, Hormones, Blood

What are the two layers of the serous pericardium?

• Fibrous and tunica intima

• Epineurium and perineurium

• Endomysium and tunica intima

• Parietal and visceral

What type of muscle is used to form the posterior ridges of the right atrium?

• smooth

• areolar

• pectinate

• skeletal

What structure is not apart of the heart?

• interatrial sulcus

• interatrial septum

• interventricular septum

• interventricular sulcus

which of the following statements is true?

• semilunar valves have two cups

• the mitral valve is the only valve in the heart that has two cups

• the tricuspid valve is another name for the semilunar valve

• atrioventricular valves prevent backflow into the ventricles

Chordae Tendinea connects ______ to the _______.

• pulmonary trunk, right ventricle

• aorta, left ventricle

• semilunar valve cups, papillary muscles

• atrioventricular valve cusps; papillary muscles

what structure is not used to connect cardiomyocytes to another?

• gap junctions

• desmosomes

• pericardium

• intercalated discs

How many millivolts does it take for a pacemaker cells to depolarize?

• +30 mV

• -40mV

• -55mV

• -70mV

What causes the atrioventricular node impulse delay when it is stimulated?

• Node fibers have a smaller diameter and have fewer gap junctions

• calcium and potassium channels does not open up properly to trigger action potential

• sinoatrial node briefly blocks impulse from traveling to atrioventricular node

• there is no delay

What happens to cardiac action potential when there are low levels of potassium?

• widens the resting membrane potential and threshold potential difference which results in low chances of the action potential firing

• shorten the resting membrane potential difference, which results in an action potential firing

• widens the resting membrane potential and threshold potential difference, which results in an action potential firing

• there is no change