The endothelium is found in the ________.
- tunica intima
- tunica media
- tunica externa
- lumen
Nervi vasorum control ________.
- vasoconstriction
- vasodilation
- capillary permeability
- both vasoconstriction and vasodilation
Closer to the heart, arteries would be expected to have a higher percentage of ________.
- endothelium
- smooth muscle fibers
- elastic fibers
- collagenous fibers
Which of the following best describes veins?
- thick walled, small lumens, low pressure, lack valves
- thin walled, large lumens, low pressure, have valves
- thin walled, small lumens, high pressure, have valves
- thick walled, large lumens, high pressure, lack valves
An especially leaky type of capillary found in the liver and certain other tissues is called a ________.
- capillary bed
- fenestrated capillary
- sinusoid capillary
- metarteriole
In a blood pressure measurement of 110/70, the number 70 is the ________.
- systolic pressure
- diastolic pressure
- pulse pressure
- mean arterial pressure
A healthy elastic artery ________.
- is compliant
- reduces blood flow
- is a resistance artery
- has a thin wall and irregular lumen
Which of the following statements is true?
- The longer the vessel, the lower the resistance and the greater the flow.
- As blood volume decreases, blood pressure and blood flow also decrease.
- Increased viscosity increases blood flow.
- All of the above are true.
Slight vasodilation in an arteriole prompts a ________.
- slight increase in resistance
- huge increase in resistance
- slight decrease in resistance
- huge decrease in resistance
Venoconstriction increases which of the following?
- blood pressure within the vein
- blood flow within the vein
- return of blood to the heart
- all of the above
Hydrostatic pressure is ________.
- greater than colloid osmotic pressure at the venous end of the capillary bed
- the pressure exerted by fluid in an enclosed space
- about zero at the midpoint of a capillary bed
- all of the above
Net filtration pressure is calculated by ________.
- adding the capillary hydrostatic pressure to the interstitial fluid hydrostatic pressure
- subtracting the fluid drained by the lymphatic vessels from the total fluid in the interstitial fluid
- adding the blood colloid osmotic pressure to the capillary hydrostatic pressure
- subtracting the blood colloid osmotic pressure from the capillary hydrostatic pressure
Which of the following statements is true?
- In one day, more fluid exits the capillary through filtration than enters through reabsorption.
- In one day, approximately 35 mm of blood are filtered and 7 mm are reabsorbed.
- In one day, the capillaries of the lymphatic system absorb about 20.4 liters of fluid.
- None of the above are true.
Clusters of neurons in the medulla oblongata that regulate blood pressure are known collectively as ________.
- baroreceptors
- angioreceptors
- the cardiomotor mechanism
- the cardiovascular center
In the renin-angiotensin-aldosterone mechanism, ________.
- decreased blood pressure prompts the release of renin from the liver
- aldosterone prompts increased urine output
- aldosterone prompts the kidneys to reabsorb sodium
- all of the above
In the myogenic response, ________.
- muscle contraction promotes venous return to the heart
- ventricular contraction strength is decreased
- vascular smooth muscle responds to stretch
- endothelins dilate muscular arteries
A form of circulatory shock common in young children with severe diarrhea or vomiting is ________.
- hypovolemic shock
- anaphylactic shock
- obstructive shock
- hemorrhagic shock
The coronary arteries branch off of the ________.
- aortic valve
- ascending aorta
- aortic arch
- thoracic aorta
Which of the following statements is true?
- The left and right common carotid arteries both branch off of the brachiocephalic trunk.
- The brachial artery is the distal branch of the axillary artery.
- The radial and ulnar arteries join to form the palmar arch.
- All of the above are true.
Arteries serving the stomach, pancreas, and liver all branch from the ________.
- superior mesenteric artery
- inferior mesenteric artery
- celiac trunk
- splenic artery
The right and left brachiocephalic veins ________.
- drain blood from the right and left internal jugular veins
- drain blood from the right and left subclavian veins
- drain into the superior vena cava
- all of the above are true
The hepatic portal system delivers blood from the digestive organs to the ________.
- liver
- hypothalamus
- spleen
- left atrium
Blood islands are ________.
- clusters of blood-filtering cells in the placenta
- masses of pluripotent stem cells scattered throughout the fetal bone marrow
- vascular tubes that give rise to the embryonic tubular heart
- masses of developing blood vessels and formed elements scattered throughout the embryonic disc
Which of the following statements is true?
- Two umbilical veins carry oxygen-depleted blood from the fetal circulation to the placenta.
- One umbilical vein carries oxygen-rich blood from the placenta to the fetal heart.
- Two umbilical arteries carry oxygen-depleted blood to the fetal lungs.
- None of the above are true.
The ductus venosus is a shunt that allows ________.
- fetal blood to flow from the right atrium to the left atrium
- fetal blood to flow from the right ventricle to the left ventricle
- most freshly oxygenated blood to flow into the fetal heart
- most oxygen-depleted fetal blood to flow directly into the fetal pulmonary trunk