Blood and immune L2

Question 1

Distinctive features of Red blood cells

Answer 1

• biconcave disc shape
• No nuclei or organelles
• Filled with haemoglobin (red protein) which binds to oxygen
• 6-8 micrometers.

Question 2

size of an Angstrom in nm

Answer 2

1 Angstrom=0.1nm or 10,000 Angstrom = 1000nm = 1 micron

Question 3

How do red blood cells orientate/come about?

Answer 3

Orientate from myeliod stem cells in bone marrow which goes in the following steps:
Stems cells differentiate into proerythoblasts, and then early erythroblasts, late erythroblast (hamoglobin accumulation), normal blast, reticulocytes looses nucleus staying in bone marrow for serval days before entering circulation, after time in circulation mature and become erythrocyte. This is called Erythropeosis.

Question 4

Time RBC spend in the blood system

Answer 4

120 days.

Question 5

What happens to the RBC after 120 days?

Answer 5

Destroyed by spleen, liver and bone marrow. Destruction by macrophages which engulfs RBC and breaks down into haemoglobin, further broken down into globin and heme, global into amino acids and heme= Bilirubin and iron

Question 6

RBC contain what on their surface?

Answer 6

RBC contain glycolipids in the plasma membrane that act as antigens that account for the different various types of blood groups such as ABO .

Question 7

Proteins within blood includes…

Answer 7

Lysozome, haemoglobin, Serum Albumin, Immunoglobulin

Question 8

Lysozome structure

Answer 8

129 amino acid chain, contains both alpha helical and beta pleated sheets.

Question 9

Hemoglobin structure

Answer 9

4 chains consisting of 2 alpha and 2 beta pleated sheets.

Question 10

Serum Albumin structure

Answer 10

585 amino acids in a single chain

Question 11

immunoglobulin structure

Answer 11

2 chains consisting of 2 heavy chains and 2 light chains.

Question 12

Haemoglobin is..

Answer 12

The red protein, made up of the four chains, within each chain is a heme group which means there are 4 heme groups in total. Each heme group has a iron in the centre of each group at which O2 binds.

Question 13

Co-operative binding

Answer 13

Seen in the heme group.
Once an oxygen molecule binds, the heme group changes shape in such a way that other sites change to more likely bind oxygen. This method makes red blood cells very good at oxygen accepting when travelling through capillaries when oxygen is diffusing through the alveoli.

Question 14

Allosteric inhibitation

Answer 14

Haemoglobin is allosterically inhibited by CO2.

Question 15

Blood concentration of haemoglobin

Answer 15

is approximately 150mg/mL

Question 16

Haemoglobin concentration within red blood cells is…

Answer 16

approximately 340mg/mL

Question 17

The structure of haemoglobin

Answer 17

3 dimensional shape determined by protein crystallography by Max Perutz in 1968

Question 18

Embryos, fetal and adults all have different genes coding for haemoglobin protein

Answer 18

This is because they all have different bit of DNA that code for the particular RNA.

Question 19

Size of haemoglobin molecule in angstrom

Answer 19

40 A

Question 20

Size of bond in haemoglobin in Angstrom

Answer 20

1 A

Question 21

Wavelength of light

Answer 21

500nm or half of a micron

Question 22

A type of mutation in haemoglobin

Answer 22

Sickle cell disease. The 6th amino acid, where glu changes to val results in the cells structure changing. The haemoglobin ends crystallise (in low oxygen parts of the body) forming sickle cell shape.

Question 23

Why may sickle cell disease be increased in a population?

Answer 23

May be selected for in high Malarial infected countries as the abnormal haemoglobin copy of the gene protects the malaria parasite from infecting RBC.

Question 24

Which gene encodes for the Serum Albumin protein?

Answer 24

ALB gene

Question 25

What is the structure of Serum Albumin protein?

Answer 25

All alpha helix secondary structure, single protein.

Question 26

Where does Serum Albumin live?

Answer 26

produced in the liver and is dissolved in blood plasma and is the most abundant blood protein in mammals (54%).

Question 27

Concentration of Serum Albumin in serum?

Answer 27

35mg/mL

Question 28

Function of Serum Albumin?

Answer 28

Serves as a carrier for small molecules e.g lipid, hormones and man made drugs. E.g Aspirin

Question 29

Importances of Serum Albumin in medicine

Answer 29

• understand how hormones move around the body
• Made made drugs can be developed to correctly bind to Serum Albumin where the drug will be transported around the body.

Question 30

Immunoglobulin structure

Answer 30

4 amino acids chains - 2 H and 2L
Y shaped molecule with control and variable sections.
The variable sections are where antigens bind to the molecule.

Question 31

Function of immunoglobulin (Antibodies)

Answer 31

Key role in immune system. Location of much of the prior knowledge of the immune system. in order to recognise threats- the immune system has to know the bacteria out there via molecules binding to specific antigens. Built into structure of antibody molecule and related molecules on the surfaces of cells such as T-cells (T-cell receptors).

Question 32

Amino acid sequences of antibodies

Answer 32

Each different antibody has a different amino acid sequence.

Question 33

Variable region

Answer 33

Part of the antibody molecules that differs in each antibody molecule.

Question 34

Antigen binding site structure

Answer 34

made up of amino acids from the heavy chain and light chain. The chains are held together by disulphide bonds.

• Modular structure.
• consist of simple single domain repeated multiple times 12 in antibody molecule.

Question 35

Antigen?

Answer 35

Any foreign particle in the body.

Question 36

Epitope ?

Answer 36

Part of the antigen that is recognised by the antibody molecule.

Question 37

Domain of the antibody?

Answer 37

Bit of amino acid sequence that folds up into a C shape.

Question 38

How are variable parts created in the antibody?

Answer 38

Mutations.