Normal red cells

Question 1

do red blood cells have a nucleus?

Answer 1

no

Question 2

red blood cells are full of ________ to carry oxygen

Answer 2

haemoglobin

Question 3

do red blood cells have mitochondria?

Answer 3

no

Question 4

can red blood cell divide

Answer 4

nope, can’t divide, can’t replace damaged proteins, limited lifespan

Question 5

why are red blood cells flexible

Answer 5

to squeeze through capillaries (the cells are bigger than the capillaries)

Question 6

haemaglobin function

Answer 6

• deliver oxygen to tissues
• act as a buffer for H+
• CO2 transport

Question 7

do we want to keep water in or out of red blood cells

Answer 7

out (we do this by the sodium-potassium pump)

Question 8

how many subunits is haemoglobin made of

Answer 8

4 (2 alpha and 2 beta)

Question 9

what state does iron need to be in to carry oxygen?

Answer 9

Fe2+
(oxygen does NOT bind to Fe3+)

Question 10

red cell production is regulated by ____________

Answer 10

erythropoietin

Question 11

what makes the hormone erythropoietin?

Answer 11

kidney

Question 12

hypoxia sensed by kidney —-> __________ produced —-> __________ stimulates red cell production

Answer 12

erythropoietin

Question 13

where does red cell destruction normally occur?

Answer 13

spleen (and liver)

Question 14

what is the average red cell lifespan

Answer 14

120 days

Question 15

aged red cells are taken up by _________

Answer 15

macrophages

Question 16

red cell contents are recycled, true or false

Answer 16

true

Question 17

old red cells - what are globin chains recycled to?

Answer 17

amino acids

Question 18

old red cells - heme group broken down to ____ and _________

Answer 18

iron and bilirubin

Question 19

old red cells - bilirubin is taken to _____ and conjugated

Answer 19

liver

Question 20

what is the glucose to lactate process/pathway is called?

Answer 20

glycolysis or Embden-Meyerhof pathway

Question 21

in glycolysis, _____ acts an electron donor preventing
oxidation of
Fe 2+ to Fe 3+
and generating
NAD+ in the process

Answer 21

NADH

Question 22

_______ protects us from hydrogen peroxide, defense against oxidative damage

Answer 22

glutathione (GSH)

Question 23

what is the rate limiting enzyme in the process of glutathione reacting with hydrogen peroxide to protect us from oxidative damage?

Answer 23

G6PD

Question 24

what does a red cell need?

Answer 24

• a way of generating energy i.e. ATP
• a way to keep Fe2+ from becoming Fe3+ (ie stop it oxidising)
• a way to prevent oxidative damage to cellular enzymes and Hb from free radicals
• a way of buffering CO2 for transport
• a way of holding onto oxygen in transport and dumping it in hypoxic environments
• a way of improving tissue oxygen delivery when it needs it most (when anaemic or when high demand for oxygen)

Question 25

red cell - is osmotic pressure high or low

Answer 25

high (it is stuffed with Hb)

Question 26

oxygen binding to Hb kinetics - the allosteric effect

Answer 26

as first oxygen binds to a haem in one subunit, the Hb shape changes

this alters how easy it is for the next O2 to bind to the haem in the next subunit

and this changes the shape again…

therapeutically this is helpful.

Question 27

fetal Hb subunits

Answer 27

has 2 alpha and 2 gamma subunits

Question 28

what can hold onto oxygen better - adult or foetal haemaglobin?

Answer 28

foetal

Question 29

what is 2,3 BPG

Answer 29

a small molecule found in red blood cells

2,3-BPG binds to hemoglobin molecules within red blood cells, causing a conformational change that decreases the affinity of hemoglobin for oxygen.

allows more oxygen to be delivered to tissues in stressful situations??

it is increased in chronic anaemia