Immune System and Blood Pt.1

Question 1

What kind of tissue is blood

Answer 1

Connective tissue

Question 2

What is blood composed of

Answer 2

Cells
1. Erythrocytes (red blood cells) for oxygen transport
2. Thrombocytes (platelets), protein fragments for coagulation (blood clotting)
3. Leukocytes (white blood cells or WBCs) for immune responses
4.Plasma, protein-rich fluid matrix that suspends cells

Question 3

What proteins are in plasma

Answer 3

1. Albumin contributes to plasma colloid osmotic pressure (COP), which holds water in vascular space
2. Globulins are clotting factors, enzymes, and antibodies
   3.Fibrinogen forms fibrin threads essential to blood clotting
   4.Transferrin is for iron transport

Question 4

When you put blood into a centrifuge it separates

Answer 4

Hematocrit

Question 5

What is Hematocrit

Answer 5

The ratio of red blood cells to plasma expressed as a percentage

Question 6

Hematopoiesis

Answer 6

The synthesis of blood cells , precursors formed in bone marrow

Question 7

What is hematopoiesis controlled by

Answer 7

Chemical signalers called cytokines

Question 8

Erythrocutes are formed by

Answer 8

Large, nucleated precursors called erythroblasts

Question 9

Before maturation, nucleus is

Answer 9

Pinched off and phagocytized by immune cells in bone marrow

Question 10

Mature erythrocytes lack

Answer 10

Nucleus and mitochondria

Question 11

Mature erythrocytes are

Answer 11

Biconcave disks supported by cytoskeleton

Question 12

Mature erythrocytes are filled

Answer 12

With enzymes and hemoglobin

Question 13

RBCs live in circulation about

Answer 13

Four months

Question 14

After destruction RBCs

Answer 14

1. Amino acids are recycled
2. Heme remnants converted by spleen/liver to colored pigment called bilirubin
3. Bilirubin incorporated into bile, giving normal color to feces/urine
4. Excess bilirubin in blood causes jaundice, a yellow cast of skin/whites of eyes

Question 15

Respiratory pigments

Answer 15

Proteins animals transport most of their O2 bound to

Question 16

The respiratory pigment of almost all vertebrates and many invertebrates is

Answer 16

Hemoglobin

Question 17

What is hemoglobin composed of? (Plus -)

Answer 17

Four subunits (polypeptide chains), each with an iron-containing heme group
-A single hemoglobin molecule can carry four molecules of O2, one molecule for heme group
-Hemoglobin binds oxygen reversibly, loading it in the lungs and releasing it in other parts of the body

Question 18

Hemoglobin is composed of

Answer 18

Four globin molecules
-Four heme groups
-Several isoforms

Question 19

Heme

Answer 19

A porphyrin ring with an iron (Fe) atom at its center
-Iron comes from diet
-Transported in blood by transferrin
-Iron taken up in bone marrow for developing RBCs
-Excess iron stored in liver by ferritin

Question 20

Hemoglobin binds O2 cooperatively

Answer 20

-When O2 binds one subunit, the others change shape slightly, resulting in their increased affinity for oxygen
-When one subunit releases O2, the others release their bound O2 more readily

Question 21

Cooperativity can be demonstrated by

Answer 21

The dissociation curve for hemoglobin

Question 22

Binding of hemoglobin to O2 is also

Answer 22

pH sensitive

Question 23

Anemia

Answer 23

Is the reduction in the total number of erythrocytes in the circulating blood or in the quality or quantity of hemoglobin.

Question 24

What is anemia caused by?

Answer 24

1. Acute or chronic blood loss
2. Impaired erythrocyte production
   E.g, aplastic anemia from bone marrow damage
3. Increased erythrocyte destruction
   E.g., sickle cell anemia from genetic mutation leading to fragile, abnormally shaped RBCs
4. Nutritional deficiencies
   E.g., iron deficiency anemia

Question 25

Hemostasis

Answer 25

Is the process of stopping bleeding

Question 26

What is hemostasis accomplished by

Answer 26

1. Coagulation (clotting) system –
   -Proteins in the blood
   -Series of zymogens (enzyme precursors) called factors that activate each other
2. Platelets (cell fragments)

Question 27

Platelets

Answer 27

Are cell fragments in the blood important for coagulation (blood clotting)

Question 28

Megakaryocytes (platelets)

Answer 28

Small fragments of precursor cells

Question 29

Platelets characteristics

Answer 29

-No nucleus, but contain mitochondria, smooth endoplasmic reticulum, granules (membrane-bound vesicles containing cytokines & growth factors)
-10 day life span
-Important for stopping blood loss, immunity, and inflammation

Question 30

What are the steps of hemostasis

Answer 30

1. Vasoconstriction is immediate constriction of damaged vessels
2. Platelets adhere to exposed collagen of damaged vessel forming a platelet plug
   3.Tissue factors of the coagulation cascade form a fibrin protein mesh that stabilizes the platelet plug into a clot
3. Plasmin dissolves fibrin as the damaged vessel is repaired

Question 31

What two mechanisms limit the extent of clotting

Answer 31

1. Inhibition of platelet adhesion
   2.Inhibition of the coagulation cascade and fibrin production

Question 32

What is an example of anticoagulant

Answer 32

Heparin
-Activates anti-thrombin (thrombin is a factor of the coagulation system)
-Heparin is endogenous (produced by the body) but can be given as exogenous (outside the body- i.e., drug