Hemoglobin and iron metabolism.

Question 1

hemoglobin LIST

Answer 1

structures
functions
types
clincials

she
found
two
cats

Question 2

hemoglobin - structure 1

Answer 2

hemoglobin is a quatenary tetramer protein

Question 3

hemoglobin - structure 2

Answer 3

HemoglobinA = x2 alpha subunits
HemoglobinB = x2 beta subunits
= 4 polypeptide chains

Question 4

hemoglobin - structure 3

Answer 4

1 hemoglobin = 4 subunits = 4 heme group = iron centre = x1 oxygen binded

Question 5

hemoglobin - function 1

Answer 5

OXYGEN TRANSPORT

• hemoglobin + oxygen = oxyhemoglobin
• lungs -> tissues

Question 6

hemoglobin - function 2

Answer 6

CARBON DIOXIDE TRANSPORT

hemoglobin + carbon dioxide = carbo-amino-hemoglobin

• tissues -> lungs

Question 7

hemoglobin - function 3

Answer 7

BUFFERING

hemoglobin acts a as buffer to maintain correct blood pH levels in terms of H+/HCO3=

Question 8

hemoglobin - function 4

bohr effect 1

Answer 8

BOHR EFFECT

• more co2 -> diffuses into blood

Question 9

hemoglobin - function 4

bohr effect 2

Answer 9

• co2 + h2o = h2co3 = lowers blood pH

Question 10

hemoglobin - function 4

bohr effect 3

Answer 10

• hemoglobin has less affinity to bind to oxygen, so oxygen is left behind + released into tissues

Question 11

hemoglobin - function 4

bohr effect 4

Answer 11

• oxygen dissociation curve turns right

Question 12

hemoglobin - function 4

bohr effect 5

Answer 12

ensures active tissues producing more co2 get more o2 to improve efficiency delivery

Question 13

hemoglobin - function 5

Answer 13

HALDANE EFFECT

hemoglobin + oxygen = makes it easier to release co2 in lungs

Question 14

hemoglobin - type 1

Answer 14

ADULT HEMOGLOBIN

• x2 hemoglobin A
• x2 hemoglobin B

Question 15

hemoglobin - type 2

Answer 15

FETAL HEMOGLOBIN

• x2 hemoglobin A
• x2 hemoglobin F

HbF has higher affinity for oxygen than HbA = oxygen transfer from mother -> foetus

Question 16

hemoglobin - type 3

Answer 16

SICKLE HEMOGLOBIN

HemoglobinS
- abnormal variant due to sickle cell anemia
- caused by point mutation of HBB gene on chromosome 11
- valine overtakes glutamic acid on position 6 of HemaglobinB chain

Question 17

hemoglobin - clinical 1

Answer 17

ANEMIA

• lack of Hb for Fe transport
• fatigue/ weakness/ dizziness

Question 18

hemoglobin - clinical 2

Answer 18

CO POISONING

• Hb + CO carboxyhemoglobin

Question 19

hemoglobin - clinical 3

Answer 19

normal Hb = 15g/dL

Question 20

iron metabolism - LIST

Answer 20

clinicals
recycling
usage
sources
absorption
transport

CRUSTAS

Question 21

iron metabolism - clinical 1

Answer 21

IRON DEFICIENCY

• less Hb in blood, less iron binding, less o2 transport
  = weakness, fatigue, dizziness

Question 22

iron metabolism - clinical 2

Answer 22

IRON OVERLOAD

iron supplements = liver damage

Question 23

iron metabolism - 2

Answer 23

RECYCLING

iron is recycled by macrophages in spleen/ liver

Question 24

iron metabolism - 3

Answer 24

USAGE

iron is an essential nutrient to transport oxygen in blood

Question 25

iron metabolism - source 1

Answer 25

heme iron
- animal meat products
- small intestine epithelial cells (enterocytes)

Question 26

iron metabolism - source 2

Answer 26

non heme
- plant grain products
- Fe3+ -> Fe2+ reduced by duodenal cytochrome B

Question 27

iron metabolism - transport 1

Answer 27

once iron enters body it binds to transferrin plasma protein
taken to tissues/ organs
- bone marrow Hb synthesis
- liver for storage
transferrin binds to ferric -> ferrous (reduced( for storage

Question 28

iron metabolism - transport 2

Answer 28

lacto-ferrin found in mucosal secretions for immune function

Question 29

iron metabolism - 6

Answer 29

ABSORPTION

hepcidin = liver based hormone controlling iron in circulation

negative feedback mechanism

Question 30

iron metabolism - 7

Answer 30

STORAGE

• ferritin = excess iron storage in liver/ bone marrow/ muscle
• hemos-iderin = complex of excessive iron storage