Quiz 11 - Blood

Question 1

composition and functions of blood

Answer 1

blood acts as transport medium to distribute substances to and from body tissues

Question 2

basis functions of blood

Answer 2

distribution
regulation
protection

Question 3

distribution by blood

Answer 3

transports:

• O2 from lungs and nutrients from GI tract to cells
• metabolic wastes from cells to lungs and kidneys for elimination
• hormones from endocrine glands to target organs

Question 4

regulation by blood

Answer 4

maintains:

• body temperature by absorbing and distributing heat
• pH in body tissues using buffer systems
• fluid volume in circulatory system

Question 5

protection by blood

Answer 5

prevents:

• blood loss by initiating clot formation when a vessel is broken
• infections by synthesizing and utilizing antibodies and white blood cells against pathogens

Question 6

components of blood

Answer 6

plasma plus formed elements and hematocrit (Hct)

Question 7

hematocrit

Answer 7

% of RBCs in centrifuged blood sample

- when centrifuged, blood separates into heavier formed elements on bottom and lighter plasma on top

Question 8

average Hct for men and women

Answer 8

men ~46%

women ~ 42%

Question 9

physical characteristics of blood

Answer 9

• more dense than water (viscous)
• alkaline pH = 7.4
• temp = 38C
• accounts for ~7% of body weight
• avg volume: males ~5L, women ~4L

Question 10

components of plasma

Answer 10

water (90% of plasma)
plasma proteins (8%)

Question 11

types of plasma proteins

Answer 11

albumin
fibrinogen
globulins

Question 12

albumin

Answer 12

regulates osmotic pressure (water balance)

Question 13

fibrinogen

Answer 13

clotting proteins

Question 14

globulins

Answer 14

transport lipids and antibodies

Question 15

substances transported by blood

Answer 15

respiratory gasses
nutrients
hormones
electrolytes

Question 16

formed elements

Answer 16

erythrocytes
leukocytes
platelets

Question 17

structure of erythrocytes

Answer 17

• biconcave shape (increases surface area, stackable, flexible)
• no nucleus (unable to divide, grow, or synthesize proteins)
• > 97% hemoglobins
• no mitochondria (ATP is generated anaerobically)

Question 18

function of erythrocytes

Answer 18

carry O2 from lungs to tissue and carry CO2 from tissues to lungs

Question 19

hemoglobin

Answer 19

major protein of RBCs that carries oxygen

• reg pigment: oxygenated (red), deoxygenated (dark red)
• 4 heme molecules: each with an iron that can bind one oxygen

Question 20

erythropoietin

Answer 20

hormone released by kidneys which stimulates red blood cell production

Question 21

release of erythropoietin is triggered by…

Answer 21

• hypoxia due to decreased RBCs
• decreases in oxygen availability
• increase tissue demand for oxygen

Question 22

fate and destruction of erythrocytes

Answer 22

• life span of a RBC = 100-120 days
• dying and damaging RBCs are engulfed by macrophages in spleen or liver
• heme and global are separated and the iron recycled

Question 23

leukocytes

Answer 23

• important in body’s defense against foreign invaders
• less numerous than RBCs
• make up 1% of total blood volume

Question 24

types of leukocytes

Answer 24

neutrophils
eosinophil
basophil
lymphocyte
monocyte

Question 25

neutrophils

Answer 25

• multi-lobed nuclei
• most abundant of WBCs
• phagocytize bacteria
• 1st of the WBCs to arrive at injury site during inflammation

Question 26

eosinophil

Answer 26

• bi-lobed nuclei
• 1-4% of WBCs
• release enzymes that digest large parasites
• lessen severity of allergies

Question 27

basophil

Answer 27

• most rare of WBCs

-

Question 28

lymphocyte

Answer 28

• > 25% of WBCs
• primary cells of lymphatic system found mostly in lymphoid tissues (some circulate in blood)
• become B and T cells, important in immune system

Question 29

monocyte

Answer 29

• 4-*% of WBCs
• largest of leukocytes
• arrive at injury site shortly after neutrophils, entering tissue and become macrophages

Question 30

platelets

Answer 30

cell fragments

• structure: small fragments broken off from megakaryocytic in bone marrow
• function: forms platelet plug that seals injured blood vessel wall