Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
41 Cards in this Set
- Front
- Back
|
What are the 3 layers of vessel walls?
|
Intima (innermost)
Media (middle) this is smooth muscle controlling diameter - thick part - most muscular Externa (outermost) |
|
|
What color are veins? Why?
|
Blue - carry deoxygenated blood
|
|
|
What type of membrane does an artery have?
|
Internal/External elastic
|
|
|
Describe the media
|
Thick with smooth muscle and elastic fibers
|
|
|
Describe externa
|
Contains collagen and elastic fibers
|
|
|
What are the 5 characteristics of a typical vein?
|
Usually flattenned with a thin wall
Endothelium is often smooth Internal/External elastic membrane absent Media is thin with smooth muscle and collagen fibers Externa has collagen, elastic fibers and smooth muscle. |
|
|
Characteristics of a continuous capillary: (7 total)
|
Epithelium is complete - No Holes
Permits diffusion of water, small solutes and lipid-soluble materials Located in almost all tissues except cartilage Average diameter 8 micro mm which allows blood cells to go through single file. No Media or Externa No Proteins (ie albumin) |
|
|
The Characteristics of a fenestrated capillary are: (3 total)
|
Capillary walls contain windows (many openings)
Permits rapid exchange of large peptides Choroid plexus of brain - endocrine glands |
|
|
What are sinusoids and what do they do?
|
Gaps between adjacent endothelial cells and basal lamina
Permits free exchange of large proteins Found in Liver, bone marrow, spleen, pituitary and adrenal glands. |
|
|
What is interstitium?
|
The area that holds fluid within a tissue.
|
|
|
What are venous valves?
|
They are found in smaller veins that cannot overcome the force of gravity in order to return blood.
They only allow blood flow in one direction (towards the heart) Muscles act as a blood pump. |
|
|
What is the distribution of blood within the body?
|
30% (1.5 Litres) in heart, arteries & capillaries
70% (3.5 Litres) in the venous system - 1/3 of venous blood can be found in liver, bone marrow and skin |
|
|
What is venous reserve?
|
Amount of extra blood in liver, skin and lungs which can be shifted to general circulation.
|
|
|
What is the primary drive for exchange between blood and interstitium?
|
Capillary pressure
|
|
|
Neural and hormonal regulation controls what? (3)
|
Cardiac output
venous pressure peripheral resistance |
|
|
Describe the relationship of flow with pressure and resistance?
|
Flow is directly related to pressure. If pressure increases flow increases.
Flow is inversely related to resistance. If resistance increases the flow will decrease. |
|
|
What is the relationship of Reistance and radius.
|
They are exponentially related. If radius is increased a little bit - the resistance will go down dramatically and vice versa.
|
|
|
What is the measurement for blood pressure?
|
mmHg
|
|
|
What is the mean arterial blood pressure?
|
It's the average of systolic and diastolic pressure.
|
|
|
What are the blood solutes?
|
Molecules that are dissolved in blood.
ie. albumin, nacl etc... |
|
|
What is hydrostatic pressure?
|
Results from the heart contracting
Water is pushed across the capillary into the interstitium. |
|
|
How do you calculate pulse pressure?
|
Systolic minus diastolic pressure.
|
|
|
How do you calculate Mean Arterial Pressure?
|
1/3 Pulse Pressure + diastolic.
|
|
|
Define diffusion in blood. What diffuses in blood?
|
Diffusion - the movement of molecules from a higher concentration to a lower concentration.
In blood - everything but plasma proteins move. |
|
|
Define Filtration. On which side of the heart does filtration occur?
|
Hydrostatic pressure pushes water, Na, and glucose across capillary membrane into the interstitium.
This occurs on the arterial side. |
|
|
What are the 4 important functions of capillary filtration and resorption.
|
Ensures that plasma and interstitial fluid are in constant communication.
It accelerates the distibution of nutrients, hormones, and dissolved gases throughout tissues. Assists in the transport of insoluble lipids and tissue proteins that cannot enter the bloodstream by crossing the capillary walls. It has a flushing action that carries bacterial toxins and other chemical stimuli to lymphoid tissues and organs responsible for providing immunity to the disease. |
|
|
Define vasodilation and name 4 causes.
|
Vasodilation is the opening of a vessel.
Vasodilators are Lactic acid Decreased tissue oxygen levels elevated local temperature Increased CO2 levels |
|
|
Define vasoconstrictor and what may cause this.
|
Vasoconstriction is the closing of a vessel.
Prostaglandins and thromboxanes released by platelets and white blood cells. |
|
|
Colloid Osmosis is:
|
A concentration of molecules in a fluid.
|
|
|
What are 3 homeostatic mechanisms used in cardiovascular regulation?
|
Autoregulation
Neural Mechanisms Endocrine mechanisms |
|
|
What is a baroreceptor?
|
Baroreceptors in carotid sinuses and aortic sinuses monitor the blood pressure.
|
|
|
What is atrial reflex?
|
The right atrium baroreceoptor monitors right atrial pressure.
It adjusts cardiac output to match venous return. |
|
|
In neural regulation, What is responsible for vasoconstriction?
|
Sympathetic adrenergic secretion
|
|
|
What are chemoreceptors?
|
In carotid bodies, they monitor Oxygen, Carbon dioxide and pH levels.
They are involved in respiratory activities. |
|
|
What hormones stimulate cardiac output and vasoconstriction?
|
Epinephrine and Norepinephrine.
|
|
|
Define Phlebitis
|
Infalmation of a vein
|
|
|
What happens to the descending aorta at or near the belly button?
|
It splits into the right and left common iliac.
|
|
|
What does the superior mesenteric artery feed into?
|
Small intestine.
|
|
|
What does the inferior mesenteric artery feed into?
|
Left side of colon
|
|
|
Where are the intercostal arteries found?
|
They lie along the ribs.
|
|
|
What are the great vessels?
|
Left and Right common catotid and left and right subclavian
|
