sem 1: Red Blood Cell

Question 1

what is the rbc capable of doing in order to traverse the microvascular system

Answer 1

deform without fragmentation- flexible- can fit into small gaps

Question 2

what 3 things does the rbc not contain

Answer 2

nucleus
ER
mitochondria

Question 3

outer hydrophilic lipid layer:

Answer 3

glycoproteins
glycolipids
proteins

Question 4

central hydrophobic layer:

Answer 4

proteins
cholestrol
phospholipids

Question 5

inner hydrophilic layer

Answer 5

cytoskeletal proteins to support lipid bilayer

Question 6

which phospholipid remains on inside because macrophages detect it and phagocytose them

Answer 6

phosphatidyl serine (eat me signal)

Question 7

what is the relationship between membrane and plasma cholestrol

Answer 7

free equilibrium

Question 8

what would happen to the RBC if there is increased cholestrol

Answer 8

appear distorted- aconthocytosis

Question 9

what do the cells become after aconthocytosis

Answer 9

target cells- increase in haemoglobin in center and outer region of RBC

Question 10

peripheral proteins (4)

Answer 10

spectrin
ankyrin
actin
proein 4.1

Question 11

integral proteins

Answer 11

glycophorins
Band 3
surface receptors
Na+/K+ ATPase

Question 12

what does spectrin do

Answer 12

1. binds with other peripheral proteins from cytoskeletal network of microfilaments
2. controls biconcave shape and deformability of cell

Question 13

what does ankyrin do

Answer 13

anchors lipid bilayer to membrane skeleton

Question 14

what does protein 4.1 do

Answer 14

stabilises interaction of spectrin with actin

Question 15

what are the functions of the membrane (4)

Answer 15

1. shape- provides optimum SA:V ratio
2. provides deformability and elasticity
3. regulated intracellular cation concentration
4. acts as interface between cell and environment through membrane surface receptors

Question 16

what is spherocytosis due to

Answer 16

spectrin deficiency

Question 17

what cant the rbc do with spherocytosis

Answer 17

maintain shape and become spherical

Question 18

is the inner layer of phospholipids charged or not?

Answer 18

charged

Question 19

2 phospholipids on the inner layer

Answer 19

phosphatidyl ethanolamine

phosphatidyl serine

Question 20

is the outer layer of phospholipids charged or not

Answer 20

not charged

Question 21

2 phospholipids on the outer layer

Answer 21

phosphatidyl choline

sphingomyelin

Question 22

what is inbetween the charged and uncharged phospholipids

Answer 22

unesterified cholestrol

Question 23

what subunits does each haemoglobin have

Answer 23

2 alpha- globin chains

2 b-globin chains

Question 24

what is the haem a complex between

Answer 24

protoporphyrin IX and ferrous iron ion (Fe2+)

Question 25

when we were born what type was our haemoglobin mostly

Answer 25

HbF

Question 26

what did it change to as we grew

Answer 26

Hb A

Question 27

when oxygenated what gets pushed out to allow the B-chains to move closer

Answer 27

2,3-DGP

Question 28

when oxygen is unloaded, 2-3 DGP enters, what happens the B chains

Answer 28

pulled apart

Question 29

what lowers the affinity for oxygen

Answer 29

entry of 2,3-DGP

Question 30

matobolism provides energy for(4)

Answer 30

1. Maintenance of cation pumps 2. Maintenance of Hb in reduced state 3. Maintenance of reduced sulfhydryl groups in Hb and other proteins 4. Maintenance of RBC integrity and deformability

Question 31

key metabolic pathways(4)

Answer 31

1. Glycolytic or Embden-Meyerhof pathway 2. Pentose Phosphate pathway 3. Methaemoglobin Reductase pathway 4. Luebering-Rapoport shunt

Question 32

what are the main actions of the key metabolic pathways

Answer 32

use enzyes to supply energy for the system | reduce oxidants in system

Question 33

what does the glycolytic pathway do

Answer 33

generates 90-95% of energy | glucose metabolised to 2 ATP's

Question 34

what does the pentose phosphate pathway do

Answer 34

protect from oxidative damage

Question 35

what does the methaemoglobin reductase pathway do

Answer 35

maintains iron in the ferrous state

Question 36

what does the luebering rapoport shunt pathway do

Answer 36

permits accumulation of 2,3- DGP, to regulate haemoglobin affinity