A&P chapter 19

aldosterone

"increases Na re absorption at expense of K secretion"

arterioles

* smallest arteries *range in size from 0.3 mm down to 10 um *tunic media is the chief smooth muscle with a few scattered elastic fibers

capillaries

* smallest blood vessels *, A tiny blood vessel that allows an exchange of oxygen, carbon dioxide, and nutrients between blood and cells in tissue

pulse pressure

*PULSE PRESSURE=diastolic-systolic the difference between diastolic and systolic pressure

Venous system

*Veins carry blood toward hart

vascular anastomoses

*around joints and supply's to joints organs receive blood from more than one arterial branch and arteries supply

capillaries

*deliver oxygen and nutrient to cell tissue * rid carbon dioxide and waste *go to every cell and tissue

venous valves

*found in lower limbs (legs) *tortuous and dilated because of incompetent (leaky) valves

arterial tunic

*main site for histological specialization in arteries *made of smooth muscle and elastic connective tissue *smallest capillary

sinusoid capillaries

*massive pores *Found in the liver, bone marrow, spleen, and medulla high permeability *allow large molecules and even blood cells to pass blood and tissue *produce or eliminate red blood cells

baroreceptor reflexes

*more blood vessels stretched the faster they go *blood pressure rises *located in the carotid sinuses *provide major blood supply to brain

fenestrated capillaries

*oval pores large holes * permeable to fluid and small solutes then continues capillary are

blood viscosity

*resistance from flow of blood The internal resistance to flow that exists in all fluids and is related to the thickness or "stickiness" of a fluid.

chemoreceptor reflexes

*sends messages to the medulla of how many chemicals are in the blood (harder/faster) *carbon dioxide rises and PH falls or oxygen contents of the blood drop sharply *in aortic arch and large arteries that send impulses to the cardioaccerertory center * blood pressure rises and speed the blood to the hart and lungs

blood brain barrier

*small capillary in the brain that keep out everything except oxygen and nutrience *protect the brain

total blood vessel length

*smaller the vessel more blood pressure rises the longer the vessel, the greater the resistance to flow

tunic media

*smooth muscle cells and sheets of elastin

Assume a person is experiencing a hemorrhage and the HPc has dropped to 23 mm Hg at the arteriole end of the capillary. Calculate net filtration pressure (NFP) at the arteriole end of the capillary.

-2 mm Hg

venous sinuses

-flattened, dilated veins that serve as a channel for blood, lymph or CS *around the brain acts as a reserve and maintains blood pressure *supported by tissue that surrounds them *blood draining from the brain tough dura

angiotensin II

1. stimulates the secretion of aldosterone and ADH *increase in blood pressure

What is the value for the net filtration pressure (NFP) at the arteriolar end of the capillary?

10 mm Hg

Which of the following would reflect the typical net hydrostatic pressure (HP) at the arterial end of the capillary?

34 mm Hg

Calculate mean arterial pressure (MAP) if systolic blood pressure is 120 mm Hg and diastolic blood pressure is 70 mm Hg.

87 mm Hg

vasa vasorum

A network of small blood vessels that supply large blood vessels

vasodilation

A widening of the diameter of a blood vessel.

antiduretic hormones

ADH *stimulate water conservation by the kidneys

aterial natriuretic peptide

ANP *released in atria * drop in blood pressure

varicose veins

Abnormally swollen veins that lost elasticity & cause decrease blood flow

muscular arteries

Also called distribution arteries *delivers blood to specific body organs *toward capularys has less elasticity * supply's blood to hart and brain

respiratory alkalosis

Always due to hyperventilation, Deficiency is respiration such as slow or irregular shallow respirations can lead to an excessive accumulation of carbon dioxide in the blood which results in a condition called..

elastic arteries

Arteries closest to the heart *Largest in diameter ranging in 2.5 cm to 1 cm * present in all three tunics but the most in tunic media * help hart pump blood

Why is it important that blood pressure drop to lower levels as it reaches the capillary beds?

Because capillaries are fragile and extremely permeable

diastolic pressure

Blood pressure that remains between heart contractions. *hart is relaxed

hyperventilation

Breathing faster and deeper than necessary reduces carbon dioxide concentration resulting in respiratory alkalosis

venules

Capillaries merged together *range from 8-100 in diameter *carry blood to the hart

Which capillaries are the most common in the body?

Continuous capillary

vasoconstriction

Decrease in the diameter of blood vessels

respiratory acidosis

Decreased hydrogen (in PH) and below normal carbon dioxide (PCO2) level

tunica intima

Endolthelium * internal elastic membrain

blood pressure

Force exerted by blood in the arteries

Which vein is the longest in the body and empties into the femoral vein?

Great Saphenous vein.

respiratory pump

Helps move blood back to heart, Pressure changes from breathing squeeze veins, move blood towards heart

Blood from the lower limbs is returned to the heart via the _______

Inferior Vena Cava

capillary beds

Interwoven networks of capillaries form the microcirculation between arterioles and venules

Mean arterial pressure

MAP *diastolic usually last longer than systole MAP=diastolic pressure+(pulse pressure/3)

continuous capillaries

Most common - skin, muscle

capillary blood pressure

Most very permeable, so low pressure forces filtrate into interstitial spaces

aortic bodies

Name the stretch receptors located in the aortic arch:

systolic pressure

Pressure in artery blood flow * pressure in the aorta is higher than the pressure in the more distal vessels

sympathetic venoconstriction

Reduces the volume of blood in the veins layer of smooth muscle around the veins constrict under sympathetic control

The adjustment of blood flow to each tissue in proportion to its requirements at any point in time is termed autoregulation.

True

direct renal mechanism

alters blood volume independently of hormones

What blood vessel experiences the steepest drop in blood pressure?

arterioles

Which net pressure draws fluid into the capillary?

b. net osmotic pressure

sphincter closed

blood flows through metarteriole-thoroughfare channel and bypasses true capillaries

sphincter open

blood flows through true capillaries

In the capillaries, hydrostatic pressure (HP) is exerted by __________.

blood pressure

indirect renal mechanism

blood pressure drops from hemerage *regulated by kidneys *kidneys release renin into blood *liver converts angiotensin I > ACE converts to angiotensin II (stablives blood)

From what artery does the right common carotid artery arise?

brachiocephalic trunk

veins are called

capacitance vessels blood reserviors

The net hydrostatic pressure (HP) is the hydrostatic pressure in the __________ minus hydrostatic pressure in the __________.

capillary, interstitial fluid

arterial system

carries blood away from the heart

blood vessel diameter

changes frequently and significantly alters peripheral resistance, fluid close to wall flow slower than fluid in the center

venous blood pressure

changes little during cardiac cycle, small pressure gradient about 15 mm Hg, low pressure due to cumulative effects of peripheral resistance

three types of capillaries

continuous, fenestrated, sinusoidal

basil dilation

contract

muscular pump

contraction of skeletal muscles "milk" blood toward the heart and valves prevent backflow

tunic externa

elastic and collagen fiber covering, contains nerves(sympathetic ans)

The aorta is an example of a(n) __________.

elastic artery

What type of tissue is found in the walls of the arteries but not in the walls of capillaries and venules?

elastic tissue

cardiac centers

found in the medulla (brain stem) * controls hart rate and motor centers control blood pressure

intercellular clefts

gaps of unjoined membrane *small holes most permeable

hemorrihoids

inflamation of the anus; caused by pregnancy, aging and intercourse

cardiovascular center

medulla oblongata helps regulate heart rate and stroke volume

three functional adaptations critically important to venous return

muscular pump respiratory pump sympathetic venoconstriction

adrenal medulla hormones

norepinephrine and epinephrine increase blood pressure

resistance

opposition to flow and is a measure of the amount of friction blood encounters as it passes through vessels

Which artery branches off the subclavian arteries? Select from letters A-D.

posterior auricular vein

The colloid osmotic pressure in the capillary is caused by __________.

proteins in the blood

Which vessel leaves the right ventricle of the heart to take oxygen-poor, dark red blood into pulmonary circulation?

pulmonary trunk

Which vessel(s) return(s) oxygenated blood to the left atrium of the heart to complete the pulmonary circuit?

pulmonary vein

Which vessel(s) of the pulmonary circuit transport(s) oxygen-rich blood?

pulmonary veins

caratid

pulse location that can be taken on neck

postcapillary venules

smallest venules, composed of endothelium and a few pericytes

blood reserviors

systemic veins that serve as storage depots for blood that can be moved to other parts of the body if needed *35% blood in arteries

The pulse pressure is ________.

systolic pressure minus diastolic pressure

arterial blood pressure

the measure of the pressure exerted by the blood as it pulsates through the arteries *how much elastic arteries close to the hart strech * volume of blood force into them at any time

capacitance vessels

the term for veins because they have the ability to stretch. they have a large diameter and are more distensible to hold more blood. this reduces stress on the heart.

blood flow

the volume of blood flowing through a vessel , an organ, or the entire circulation *picks up oxygen

Which of the following is NOT an important source of resistance to blood flow?

total blood volume

What is the outermost layer of the blood vessel wall for an artery or vein?

tunica externa

Which layer of the typical blood vessel is constructed from simple squamous epithelium?

tunica intima

3 layers of arteries, veins, and capillaries

tunica intima tunic media tunic externa

Which layer of the typical vessel can be regulated via vasoconstriction or vasodilation?

tunica media

Factors that aid venous return include all except ________.

urinary outpu

Reabsorption of fluid into the capillary takes place at the arterial end or venous end of the capillary?

venous