Immunology

Question 1

What is the immune system

Answer 1

The immune system is a system of cells tissues and their soluble products that recognises,attacks and destroys foreign entities that the health of an individual

Question 2

What are pathogens

Answer 2

Microorganisms everywhere billions constantly on our skin and mucosae
Some organisms are pathogenic which means they cause disease
Pathogenic organisms need to penetrate a hosts body in order to survive and reproduce
The process of a pathogen entry into host is known as infection
If the pathogen destroys the normal body and cellular function then sickness ensures the host develops disease
The immune system recognises and fights pathogens

Question 3

What are the two main categories of pathogens

Answer 3

Extracellular pathogens
Intracellular pathogens

Question 4

What are extracellular pathogens

Answer 4

Do not need to enter the host cells to replicate in the the intestinal fluid and disseminate via the blood
Mostly bacteria

Question 5

What are Intracellular pathogens

Answer 5

Need to enter the hosts cells to replicate these pathogens hijacker’s cellular metabolic machinery for their own replication and disseminate via the blood
Mostly viruses
But also bacteriaa parasites

Question 6

Self and non self

Answer 6

Important to distinguish between self and non self if it’s not succesful an autoimmune disease can be triggered

Question 7

Leukocytes (white)

Answer 7

Are cells responsible for immune response they recognise the non-self coordinate the immune response and get rid of pathogens

Question 8

Resting and active leukocytes

Answer 8

Leukocytes alternate state in bases e of pathogens to an active sate triggered by recognition of pathogens
Activated leukocytes profile rate and execute a molecular programme that endows them with ability to kill the invading pathogen

Question 9

Types of immune response

Answer 9

Initial response to pathogens penetration is mediated by innate immune system if the innate immune system is unable to block the spread of the pathogen then the adaptive pathogen response is activated

Question 10

What are some initial differences between adaptive and innate

Answer 10

Innate always involved in fighting pathogenic organism
Adaptive response only activated only as needed
Innate fast and non specific
Adaptive is slower and highly selective
First response is innate and second is adaptive

Question 11

Feature is innate immunity

Answer 11

Innate response is mediated by physical and physiological barriers
Phhysical batteries did such as skin
Physiological such as stomach acid and lysozymes
Innate response mediated by leukocytes

Question 12

Specialised immune cells

Answer 12

Macrophages
Neutrophils
Natural killer cells
Dendritic cells

Question 13

What is PAMP

Answer 13

Pathogen Associatdd Molecular pattern molecules present in the pattern but subset in the host: so this allows the innate immune system to identify the non self

Question 14

The innate response

Answer 14

Leukocytes I’m loved in innate response are activated by molecules common to many pathogens
These molecules are known as the pathogens associated molecular patterns

Question 15

Cell mediated innate response

Answer 15

Leukocytes posses pattern recognition receptors that recognise PAMPs on pathogens
One the PRRs bind to the PAMPs the leukocytes are activated

Question 16

PAMPS AND PRRS

Answer 16

Common PAMPs are lipolysacharides large molecules consisting of a lipid and a polysaccharide present in the membrane a gram negative bacteria
Common PRR are toll like receptors

Question 17

Action of activated innate immune cells

Answer 17

Initiate inflammation
Secretion of molecules with two functions
Recruitment of immune cells
Aler activation of immune cells
Killing the pathogens
Eating the pathogen to get rid of it
Targeted cell lysis

Question 18

Inflammation

Answer 18

When the innate immune system identifies the pathogens initiates a process known as inflammation which is the eg real activation of the immune response to fight the attackers

Question 19

Immune cells and Inflammation

Answer 19

Vasodilation in the infected to increase blood flow and the recruitment of immune cells
Immune cells secrete messenger proteins
Chemokines signal the area of inflammation and immune cells equipped with receptor for chemokines migrate to infected areas
Cytokines stimulate activation of immune cells
Swelling redness fever are common symptoms of inflammation

Question 20

Phagocytosis extracellular pathogens

Answer 20

Phagocytosis is process of cell eating
Immune cells eat and digest the pathogen identified via PAMPs
The leukocytes able to phagocyte pathogens are macrophages neutrophils and dendritic cells
Neutrophils and macrophages are main phagocytosic cells involved in innate immune response

Question 21

Targeted cell lysis

Answer 21

This is the mechanism used by innate immune system to eliminates Intracellular pathogen
Innate immune system sacrifices the infected system sacrifices the infected cells this job is performed by natural killer cells

Question 22

Targeted cell lysis Intracellular pathogens

Answer 22

Lysis
Host cells