Brain Vessels

Question 1

What is the difference between veins, arteries and capillaries?

Answer 1

Veins = low blood pressure, carry blood toward the heart; join, merge, and converge

Arteries = thick, high blood pressure, more structured, carry blood Away from the heart branch, diverge, and fork

Capillaries = smallest blood vessels. The site of exchange of molecules between blood and tissue fluid

Question 2

The three vessel layers

Answer 2

Tuncia intima = composed of simple squamous epithelium

Tunica media = sheets of smooth muscle
-contraction —vasoconstriction
-Relaxation —vasodilation

Tunica externa = composed of connective tissue

Question 3

Lumen?

Answer 3

Central blood-filled space of a vessel

Question 4

Elastic Arteries

Answer 4

Includes the aorta and it’s major branches
-High elastin content dampe surge of blood pressure

Question 5

Muscular arteries

Answer 5

-Lies distal to elastic
-Túnicas media is thick squeeze (distributing)

Question 6

Arterioles

Answer 6

-Smallest artery
-Large arteries posses all three túnicas
-Controlled by hormones

Question 7

Capillary functions

Answer 7

Smallest blood vessel
-Diffusion and filtration

Question 8

Continuous capillaries (3)

Answer 8

-Uninterrupted lining
-Found in all tissues EXCEPT epithelial & cartilage
-Permits diffusion of water, small solutes, lipid-soluble materials etc.
-Most selective

Question 9

Fenestrated Capillaries

Answer 9

-Many fenestrations/pores (openings)
-Permit rapid exchange between plasma and interstitial fluid of water and larger solutes
-Material exchange
-Absorption & filtration
-Endocrine system

Question 10

Sinusoidal cappilaries

Answer 10

-Swisssss cheese
Large fenestrations and intercellular clefts
-Incomplete basement membrane
-Permit free exchange of water and large plasma prot
-Bone marrow (makes cells)
-Phagocytic cells monitoring blood

Question 11

Blood-Brain Barrier
(BBB)
(4 functions)

Answer 11

1. Has a tight junction
2. No intercellular clefts present
3. Selective
4. Ineffective/not a barrier against oxygen, carbon dioxide, fats, and some anesthetics

Question 12

Four vessels of the brain

Answer 12

1. Anterior cerebral
2. Middle cerebral
3. Posterior cerebral
4. Basilar

Question 13

Aneurysm

Answer 13

Widening of a blood vessel

Question 14

Three types of aneurysm

Answer 14

1. Saccular = Bulges/ballon’s on one side
2. Fusiform = Bulges/ballon’s on both sides of the vessel
3. Ruptures/hemorrhage = Blood bursting

Question 15

Three steps in hemostasis

Answer 15

1. Vascular splash: vasoconstriction of damaged blood vessels
2. Platelet plug formation
3. Coagulation or blood clotting (processes liquid)

Question 16

Hemorrhage

Answer 16

Rupture
-Blood bursting forth
-Starts to fill inside the brain

Question 17

Def of hemosasis

Answer 17

Balance
-to stop blood & have control

Question 18

Some of the possible causes of aneurysm’s

Answer 18

1. Inheritance
2. Connective tissue disorder
3. Sickle cell anemia
4. Infections
5. Trauma
6. Cigarette smoking
   7.drug & alcohol use