Erthrocyte Physiology

Question 1

Functions of blood

Answer 1

1. Deliver nutrients and O2
2. Remove waste
3. Maintain homeostasis
4. Circulation
5. Thermoregulation
6. Immune response

Question 2

What is the hematocrit formula

Answer 2

Height of RBC’s/ total height

Question 3

Normal hematocrit range

Answer 3

40%-45% adult

55% for newborn

Question 4

RBC function

Answer 4

1. Carry O2 to body
2. Carry CO2 to lungs
3. Acid/base buffering

Question 5

Globulins are not made in

Answer 5

The liver

Question 6

What is cyanosis

Answer 6

Blue color in lips and skin

-from decreased oxygen in hb

Question 7

Hematocrit is

Answer 7

% of blood that is cells

Question 8

Where does erythropoiesis occur

Answer 8

Bone marrow

Question 9

Will damage to the kidney cause anemia

Answer 9

Yes

*bodies use oxygen levels in kidneys to determine how many RBC’s we need

Question 10

What is the function of hypoxia inducible factor (HIF)

Answer 10

*regulates amount of oxygen in body by interaction with kidney

• if O2 is adequate then it is ubqinuated and destroyed
• if O2 is low then it accumulates and acts as an transcription factor to increase erythropoietin gene to make RBC and transferrin to get more iron

Question 11

Where is erythropoietin produced? Released to ? And brought for action?

Answer 11

Kidneys

Liver

Bone marrow

Question 12

What does erythropoietin do ?

Answer 12

*JAK2/STAT5 pathway

• acts on stem cells (differentiate to proerthyroblasts)
• increases maturation of RBC precursors
• prevents apoptosis of erythroid stem cells

*MAKES RBC’s

Question 13

How may oxygens can bind to hemoglobin

Answer 13

4

Question 14

The _______ influences how well oxygen can bind to heme in hemoglobin. Mutations in this will change oxygen binding

Answer 14

Peptide chain

*there are 4 peptide chains of hb [ porphyrin ring ]

Question 15

In the stomach the acidic environment favors the ____ form of iron, and that form will move into the intestine in this form

Answer 15

Ferric (3+)

Therefore moves into the intestine in the ferric state
*but enter the enterocyte in ferrous state

Question 16

T/F

Heme iron is removed from the heme by enzymatic degradation

Answer 16

True

Question 17

Iron def = ___ anemia

B12/folate def = ____ anemia

Answer 17

Microcytic

Macrocytic

Question 18

What stimulates EPO production in the kidneys?

Answer 18

1. Anemia
2. Low renal blood flow
3. Central hypoxia

Question 19

What is the oxygen carrying capacity of hemoglobin

Answer 19

1.34mL O2 / g of Hb

Question 20

Total amount of oxygen that can be carried in our blood by heme assuming every available heme has oxygen bound to it

Answer 20

Oxygen capacity

Question 21

What is the oxygen capacity equation

Answer 21

1. 34 x ___ hb/dL blood =

* given value

Question 22

The amount of oxygen that is actually being carried in our blood

Answer 22

Oxygen content

Question 23

% of available here’s with oxygen bound

Answer 23

% saturation

*determined by oxygen availability

Question 24

What is the oxygen content equation?

Answer 24

Oxygen capacity x %saturation = oxygen content

*will get O2 capacity from previous equation where you multipled by 1.34 and you willl be given %saturation

Question 25

What does RBC use ATP for?

Answer 25

1. Flexibility of membrane 2. ATPase (ion transport) 3. Maintain Fe3+ state (not Fe2+) 4. Prevent oxidation of hemoglobin

Question 26

What happens to the RCB remnants when RBC under hemolysis ?

Answer 26

Phagocytosis: - in spleen - macrophages - Hb recycled (made to bilirubin and recycled)

Question 27

Decreased RBC or Hb causes 1. Decreased O2 capacity/content 2. Decreased O2 delivery 3. Increased heart work load (too compensate)

Answer 27

Anemia

Question 28

Iron overload from inadequate hepcidin (genetic mutation) causes: 1. Cardiomyopathy

Answer 28

Hemochromatosis *normal O2 capacity/content and hemoglobin

Question 29

does oxygen saturation decrease in hemochromatosis or anemia

Answer 29

No, it in unchanged

Question 30

When iron is low transferrin is _____

Answer 30

High

Question 31

Too many RBC’s is called

Answer 31

Polycythemia

Question 32

What are the effects of polycythemia

Answer 32

- increased O2 capacity/content - THICK BLOOD (increased viscosity) - heart has to work harder

Question 33

What is secondary polycythemia ? (Physiological polycythemia)

Answer 33

[too many RBCs] * normal bone marrow * heart or lung problem

Question 34

What is primary polycythemia?

Answer 34

[too many RBC’s] *abnormal bone marrow (Making to much RBC) *thrombopoietin mutation

Question 35

What is physiological polycythemia?

Answer 35

[too may RBC] - normal bone marrow - body is responding to low oxygen levels (maybe from altitude)

Question 36

T/F | Hemoglobin Oxygen saturation will not change even if the oxygen availability changes a lot

Answer 36

True | Seen by Hb-O2 curve of

Question 37

What does a left shift in the Hb-O2 curve mean? Right shift ? What are they caused by

Answer 37

LEFT - increased hemoglobin affinity for O2 - low CO2 - High Ph - decreased temp RIGHT - decreased affinity for O2 (binds less) - high CO2 - low Ph - high temp - increased 2,3 DPG (metabolites) * IMPORTANT FOR EXCERCISE SO HB CAN LET GO OF O2 AND IT CAN GO TO THE TISSUES WHERE ITS NEEDED

Question 38

What is caused by large amounts of met-hemoglobin in the body? (Hemoglobin with Fe3+ not Fe2+)

Answer 38

Methemoglobinemia * left shift in the curve * blood is chocolate colored * cyanosis occurs *hemoglobin does not want to let go of this oxygen because of the iron state