Lecture 2: Immunoglobulins

Question 1

cells involved in the immune systems

Answer 1

• macrophages
• leukocytes
• lymphocytes

Question 2

2 complementary systems of the immune system

humoral system

Answer 2

• directed at bacterial infections and extracellur viruses(those found in in body fluids)
• consisting of antibodies or immunoglobulins Ig

Question 3

2 complementary system of the immune

cellular immune system

Answer 3

• destroy host cells infected by viruses
• destroys parasites and foreign tissues
• consists of the T lymphocytes or T cells (latter stages occur in the thymus)

Question 4

Immunoglobulins

Answer 4

• are soluble proteins of the humoral immune system that bind bacteria viruses or large molecules identified as foreign and target them for destruction

produced by B Lymphocytes or B cells(complete development in the bone ma

Question 5

Tc cells/Killer T cells/cytotoxic cells

Answer 5

consist of Tc cell receptors that ca recognise infected host cells and parasites

Question 6

receptors

Answer 6

protein molecules found on the oute surface of cells and extending through the plasma membrane, that can recognise and bind exttracellular ligand, triggering changes inside the cell

Question 7

Th cells/Helper T cells

Answer 7

participate indirectly in destruction of infected cells and pathogens by stimulating the selective proliferation of Tc and B cells that can bind to a particular antigen

Question 8

functions of the immune system

Answer 8

1. recognition of invading pathogen(dinstinct from molecular self)
2. triggering pathways to destroy molecular nonself molecules

Question 9

antigen

Answer 9

foreign macromolecules or components that invade the body and are capable of illicing an immune response

Question 10

primary immune response

Answer 10

• infection by antigen stimulates production of Ig M by B limphocytes
• which recognise and bind to antigen
• decline after 10 days
• resulting in increase of Ig G molecules

Question 11

clonal selection

Answer 11

• increase in number of immune system cells that can respond to a particular antigen after first encounter
• by creating memory cells
• allowing rapid response to the antigen previously encountered (allowing secondary response

Question 12

vaccination

Answer 12

• consists of weakend or killed virus or isolated proteins froma viral or bacterial protein coat
• does not cause infection but effectively teaches the immune system whta the virus looks like stimulating the production of memory cells

Question 13

Hiv and helper t cell

Answer 13

• Th cells are the primary target of HiV
• virus inserts viral glycoproteins in the plasma membrane
• increases permeability of the Th cells
• influx of ions and water then disrupts ionic balance causeing somotic lysis

Question 14

epitope

Answer 14

molecular structure with antigen where Ig bind

Question 15

structure of immunoglobins

Answer 15

• has 4 polypeptide chains(2 heavy and 2 light chains)
• heavy chains interact at one end through disulphide bridges the brach to interact separately with light chains
• forming a Y molecule

can be cleaved by proteases to form Fc and Fab

Question 16

lg M

Answer 16

first antibody produced in response to antigen

Question 17

lg A

Answer 17

found in external secretions, saliva, tears, mucus

Question 18

lg D

Answer 18

activates basophils

Question 19

lg E

Answer 19

confers immunity against parasites and participates in allergic reactions