Blood Physiology Flashcards Preview

MCM Exam 2 > Blood Physiology > Flashcards

Flashcards in Blood Physiology Deck (25)
Loading flashcards...
1

How is RBC production regulated?

The amount of oxygen is assessed in our kidney & liver

2

Enzyme that accumulates if O2 levels are low.

How does it act to increase O2?

HIF alpha

Continuely ubiquinated in destroyed during times of sufficient oxygen

Binds as a transcription factor and upregulates genes

3

Proteins that are upregulated by HIF alpha and is involved in upregulation of proerythroblasts.

Erthropoietin in the kidney and liver

Transferrin and its receptor

4

How does Erythropoietin increase the amount of red blood cells?

JAK2/STAT5 parhway to increase stem cell differentiation into proerythroblasts

Increases maturation rate

Prevents apoptosis of hemocytoblasts

5

What may cause anemia?

Decreased RBC or Hb

Folate/B12 deficiency

Iron deficiency

Bone marrow damage

Kidney Damage (loss of erythropoietin)

6

Microcytic anemia

Caused by deficiency in iron

7

What allows Fe++ into the cell.

Divalent Metal Transporter (DMT1)

8

Converts Fe2+ back to ferric state

Hephaestin or Ceruloplasmin

9

How much oxygen bound to Hb?

1.32 O2ml/g of Hb

10

What is the normal amount of Hb per 100 ml of blood in an average person.

15gHb/100ml

11

Formula for oxygen content

oxygen capacity x % saturation

12

Why do RBC's perform anareobic glycolysis

To maintain a flexible membrane

Ion-transport (ATPase)

Maintain Fe2+ in it's ferrous state

Prevent oxidation of Hb

13

How are RBC phagocytosed

In spleen or by other macrophages

Iron is recycled

Heme broken down to bilirubin

14

What is Polycythemia and why is it dangerous?

More oxygen carrying capacity

BUT

Blood becomes more viscous and heart must work harder to pump it.

 

Can be primary (vera) or secondary

15

What can be the mutation in Hemochromatosis?

Hepcidin Mutation (Heridtary mutation in HFE)

Blocks ferroportin to reduce intestinal uptake of iron

16

What is secondary polycethemia caused by?

Bone marrow is normal

Too many RBCs responding to altitude (physiological polycythemia)

Lung/heart disease

17

What is Primary polycethemia (Polycythemia vera) caused by?

Bone marrow is making RBC when there is no need

May be caused by a mutation in the receptor thrombopoietin.

18

Which way does an Hb-O2 curve shift in an increased affinity for O2?

To the left

19

What does the Bohr effect show about the effect of CO2 or ph on a oxygen binding curve?

High C0(which makes ph low) = left shift in affinity

Low C0(which means pH is high) = right shift in affinity

20

A temperature increase has what effect on the affinity for oxygen to Hb?

Decreases it.

21

Disease that exhibits the presence of large amounts of ferric iron (3+) in the heme.


Why is bound ferric iron dangerous?

Methemoglobinemia

Ferric iron cannot bind oxygen, this increases the affinity of oxygen in other chains so drastically that they cannot release O2.

This disease results in symptoms like anemia.

22

What are the four functions of blood?

Delivery of nutrients/oxygen

Removal of wastes

Homeostasis (thermoregulation/hormones)

Immune

23

A bluish tint in lips, skin, extremidies.

Cyanosis

24

Where is iron absorbed

20% liver

70% bone marrow

25

What is the effect of hemochromatosis?

Iron overload associated with cardiomyopathy

Reduced transferin levels