A&P2 Chapter 19: Circulation & Blood Pressure
Which vessel types may be porous enough to allow diapedesis?
- Capillaries - Venules
Which of the following is an accurate description of the tunica media?
- Circularly arranged smooth muscle cells. - The layer responsible for changing the diameter of the blood vessel
Which blood vessels carry oxygenated blood?
- Pulmonary Veins - Systemic Arteries
Peripheral resistance is:
- directly proportional to vessel length - directly proportional to blood viscosity
Sort these vessel types in the order of blood flow, starting with those that first carry blood away from the heart and finishing with those that eventually return blood to the heart.
1. Arteries 2. Arterioles 3. Capillaries 4. Venules 5. Veins
Arrange the capillary types in order of most to least permeable.
1. Sinusoid capillaries 2. Fenestrated capillaries 3. Continuous capillaries
Arrange the layers of a blood vessel wall, from superficial to deep.
1. Tunica Externa 2. Tunica Media 3. Tunica Intima
If your systolic blood pressure is 140 mm Hg and your pulse pressure is 60 mm Hg. What is your mean arterial pressure?
100 mm Hg
If your systolic blood pressure is 118 mm Hg and your diastolic blood pressure is 76 mm Hg. What is your pulse pressure?
42
Which of the following is true about afterload?
Afterload is the amount of fluid pressure generated by the ventricle during isotonic emptying
Which arteries are most directly responsible for controlling the amount of blood entering individual capillary beds?
Arterioles
Match each blood vessel type to its description.
Artery - distributes blood Veins - carries blood toward heart Capillaries - carry blood within tissues to allow for exchange
Which of the following statements most accurately describes the movement of individual red blood cells through a capillary vessel?
Capillary vessels are sometimes smaller in diameter than red blood cells, forcing the cells to squeeze through. If the vessel is larger, red blood cells must still travel through it in single file.
Which of the following is the most common capillary type in the human body?
Continuous
Match each capillary type to a location in which it is found.
Continuous - skin Fenestrated - small intestine Sinusoid - bone marrow
What would cause decreased venous return?
Decreased breathing rate
Match each of the following to its described impact on blood pressure.
Decreased heart rate - decreased blood pressure (BP) due to decreased cardiac output (CO) Increased stroke volume - increased BP due to increased CO Increased blood vessel diameter - decreased BP due to decreased radius of vessel
Fick's law states that the flow of blood through a vessel is...
Decreased if the resistance is increased.
Match each artery type to its description.
Elastic arteries - close to the heart & have relatively larger lumens Muscular arteries - thickest tunica media Arterioles - can be so small that their wall is only an endothelium and a thin layer of smooth muscle fibers
Match each region of the vasculature to the percentage of total blood volume it contains at rest.
Heart - 7% Pulmonary circulation - 9% Systemic capillaries - 7% Systemic arteries - 13% Systemic veins - 64%
Caffeine acts to _______ cardiac muscle by ________.
Increase; activation of sarcoplasmic reticulum ryanodine receptors and increased calcium release
Which feature of the capillary wall results from incomplete tight junctions?
Intercellular clefts
Excessive interstitial fluid enters blind-ended lymphatic capillaries because...
Lymphatic capillaries are at a lower fluid pressure than the interstitial space
Which type of arteries are often referred to as distributing arteries?
Muscular arteries
Which of the following is true about preload?
Preload is affected by venous return to the heart.
If I increase the cross-sectional area of a blood vessel by a factor of 2, I would expect the pressure within that blood vessel to ________ if everything else were unchanged.
Quarter
Which of the following statements regarding resistance to blood flow is correct?
Resistance to flow increases with increased blood viscosity.
Match each layer of the blood vessel wall to a description of its tissue content.
Tunica intima - simple squamous endothelium Tunica media - smooth muscle and elastic connective tissue Tunica externa - collagenous connective tissue
What is the name given to the network of smaller blood vessels providing nutrition to the walls of larger blood vessels?
Vasa vasorum
Match each component of the cardiovascular center to the description of the outcome of its activation.
Vasomotor Center - vasoconstriction of arterioles Cardioinhibitory Center - decreased heart rate and contractility Cardioacceleratory Center - increased heart rate and contracility
Distributive shock:
caused by the loss of blood vessel tone, enlargement of the blood vessels, and more
Vasomotor center:
controls the contractile activity of the smooth muscle in the tunica media
Hypovolemic shock is characterized by:
external or internal blood loss of 15% to 20%, and a loss of plasma into interstitial spaces - caused by intestinal obstructions or burns, increased blood viscosity, and more
Cardioacceleratory center and the cardioinhibitory center:
innervate the SA node, the AV node, and heart muscle via sympathetic and parasympathetic neurons, respectively.
Medullary cardiovascular center (MCC):
manages the homeostatic control mechanisms that are responsible for the short-term, nervous regulation of blood pressure
Obstructive shock:
mechanical obstruction of blood flow through the circulatory system - caused by brain damage to vasomotor center, septic or anaphylactic shock, and more
Baroreceptors:
specialized type of mechanoreceptor that respond to the amount of stretch created by pressure