LECTURE 13

Question 1

ARTERIES/ARTERIOLES

Answer 1

large diameter (endothelium/smoothmuscle/connective tissue); thick muscle walls (very strong and elastic); high pressure to permit rapid transport (elastic fibers and collagens); lead blood away from heart

Question 2

CAPILLARIES

Answer 2

small diameter (only 1 cell can pass through at a time); contact mostly body cells (about 7billion in a body); thin walls to allow molecules to cross (endothelium)

Question 3

VEINS/VENULES

Answer 3

large diameter (endothelium, smooth muscle, connective tissue); thinner muscle walls (1/3 thickness of artery, not very elastic); low pressure (slow transport), contain valves to direct flow back to heart

Question 4

ENDOTHELIUM

Answer 4

a single layer of flattened cells, providing a smooth surface that minimize resistance to the flow of blood

Question 5

VALVES

Answer 5

flaps of connective tissue which open when pushed from one side and close when pushed from the other

Question 6

REABSORPTION

Answer 6

higher pressure in the IF (venous end), about 85% recovery (the remaining 15% retuned to the blood by the lymphatic system)

Question 7

PRECAPPILLARY SPHINCTER

Answer 7

rings of smooth muscle at the capillary bed entrance, open and close to regulate BP

Question 8

VASOCONSTRICTION/VASODILATION

Answer 8

contraction/relaxation of the smooth muscles in the arteriole to increase or decrease BP (respectively)

Question 9

THOROUGHFARE CHANNEL

Answer 9

the capillaries that allow blood flow directly from arteriole to venule (always open)

Question 10

LYMPH

Answer 10

the colorless fluid, derived from IF, in the lymphatic system of vertebrates; leaks out from capillary beds

Question 11

LYMPHATIC VESSELS

Answer 11

valves in the lymph vessels prevent the backflow of fluid

Question 12

LYMPHATIC NODES

Answer 12

organs that filter lymph and play an important part in the body’s defense; infection causes the leukocytes in the lymph nodes to multiply rapidly, causing swelling and tenderness

Question 13

EDEMA

Answer 13

swelling caused by disruptions in the flow of lymph and excessive accumulation of the fluid in tissues

Question 14

SYSTOLIC PRESSURE

Answer 14

the contraction phase of the cardiac cycle; pressure at the time of ventricular contraction

Question 15

DIASTOLIC PRESSURE

Answer 15

the relaxation phase of the cardiac cycle; lower than systolic (the remaining pressure in the artery when the heart is relaxed)

Question 16

BARORECEPTOR

Answer 16

sensory neurons located in large artery walls; monitor blood pressure and relay to the medulla

Question 17

ENDOTHELIN

Answer 17

a powerful vasoconstrictor peptide produced by the endothelium, which constrict blood vessels and raise BP

Question 18

FAINTING

Answer 18

when the BP in the brain is too low to provide adequate blood flow; by causing your body to collapse, fainting effectively places your head at the same level of your heart to increase blood flow to your brain

Question 19

HYPERTENSION

Answer 19

elevated BP in the arteries (>140/90); chronic damages the endothelium that lines the arteries, promoting plaque formation

Question 20

PLAQUE

Answer 20

?

Question 21

PLASMA

Answer 21

is about 90% water at pH 7.4; solutes are inorganic salts in the form of dissolved ions, (blood electrolytes); plasma proteins influence blood pH, osmotic pressure, and viscosity; has higher protein composition than IF

Question 22

ERYTHROCYTES

Answer 22

the most numerous blood cells; bioconcave disk, lacking nuclei (in human) and mitochondria (to pack maximum Hb); very small to increase surface area to volume ratio; Hb: O2-carrying protein containing ion

Question 23

LEUKOCYTES

Answer 23

white blood cells that function in defense

Question 24

ERYTHROPOIETIN

Answer 24

a protein hormone, secreted by the kidneys to trigger erythropoiesis (misused for blood dopping)

Question 25

RED BONE MARROW

Answer 25

stem cells are located here that produce RBCs and platelets

Question 26

THROMBIN

Answer 26

an enzyme that catalyzes the formation of fibrin from fibrinogen; it also activates a factor that catalyzes thrombin formation (positive feedback mechanism)

Question 27

FIBRINOGEN

Answer 27

an inactive form of the coagulant or sealant, circulated int the blood

Question 28

FIBRIN

Answer 28

a blood coagulant aggregates into threads that form the framework of the clot

Question 29

HEMOPHILIA

Answer 29

caused by genetic mutations that blocks a step in the clotting process. minor cutes or bumps can cause excessive bleeding and bruising

Question 30

COAGULATION

Answer 30

the formation of a solid clot from liquid blood ; a cascade of complex reactions converts inactive fibrinogen to fibrin, which forms the framework of a clot

Question 31

ANITCOAGULANTS

Answer 31

molecules that work to prevent the coagulation of blood; anti-clotting factors in the blood normally to prevent spontaneous clotting in the absence of injury [asprin has an anti-platelet effect by decreasing platelet aggregation]