L30 - Immune system

Question 1

Immunology

Answer 1

Study of an organisms defense system in health and disease

Question 2

What is the immune system?

Answer 2

Organised system of organs, cells and molecules to defend the body against pathogens and fight disease

Question 3

Primary immune organs

Answer 3

Bone marrow and Thymus

Question 4

When immune system gets too excited?

Answer 4

Allergy, Asthma

Question 5

Autoimmunity

Answer 5

Immunity against yourself eg Diabites, Arthritis, multiple sclerosis

Question 6

How does the immune system fight cancer

Answer 6

Identifies Cancer cells as they look different, treatments helps immune system along with Radiation and chemotherapy

Question 7

What is a pathogen

Answer 7

A disease causing organism

Question 8

2 arms of the immune system

Answer 8

*Innate
*Adaptive

Question 9

What do immune cells do?

Answer 9

Secrete molecules, sends signals

Question 10

Biggest killers

Answer 10

SARS, TB, Malaria, HIV/AIDS

Question 11

What are microbes?

Answer 11

Small organisms that can cause disease, some microbes are pathogens

Question 12

What are viruses

Answer 12

RNA with a protein coat, needs a host cell to replicate

Question 13

Protozoa

Answer 13

Like worms

Question 14

What is the lymphatic system

Answer 14

Moving immune cells around body and connecting lymp organs

Question 15

2º lymp organs

Answer 15

Where immune cells get activated –> spleen, tonsils and lymph nodes

Question 16

Bone marrow

Answer 16

Source of stem cells that develop into cells of innate and adaptive arm, Where white blood cells are made

Question 17

Thymus

Answer 17

Some immature cells from bone marrow develop into mature T cells
*Learn to not attack self otherwise killed
*Recognise pathogens
*only 10% become mature T cells

Question 18

Spleen

Answer 18

Filters blood, site of immune response through blood

Question 19

Lymph nodes

Answer 19

Armpit, groin, throat, chin
located along lymp vessels –> takes lymphatic fluid from tissue and filter and recirculate into blood, site of immune response FOR TISSUE

Question 20

3 layers of difense

Answer 20

Moat - chem and physical barriers
Inner wall - innate arm, fast acting
Inner inner wall - Adaptive

Question 21

Physical barrier

Answer 21

Skin and mucosal surfaces

Question 22

Skin

Answer 22

*Outside is mostly dead cells + keratin (Epidermis)
*Lose every 2-4 weeks - pathogens all fall off if found on this layer
*Band of live cells under with dendritic cells, thick layer of connective tissue + blood vessels + phagocytic cells (Dermis)

Question 23

Dendritic cell

Answer 23

*Long arms to interact with other cells

Question 24

Phagocytes

Answer 24

Eats things

Question 25

Chemical defense

Answer 25

*Skin cells produce antimicrobial peptides called defensins that poke a hole/pore in bacteria --> leeches contents *Skin also produces Lysosyme to break down bacterial cells wall *Sebaceous glands - hair follicles --> sebum - low pH i.e v acidic *Sweat glands - salty, hypertonic environment --> dessicates the microbes

Question 26

Mucous membranes

Answer 26

*1-2 layer *Top layer has thin layer of mucus - traps mircobes *Epitheleal is tightly packed - hard for microvbes to get in *Goblet cells produce the mucus *Exposed to air and inside parts, hurts because they are tightly packed live cells *Constantly renewed

Question 27

Where are the mucosal mems

Answer 27

Urogenital tract, gastrointestinal, eyes - exposed to air

Question 28

Mucocillary escalator

Answer 28

The cillia - hair like projections move the mucus by beating together in unison to the pharynx to expel it or to swallow it

Question 29

What does smoking do

Answer 29

Stops the cillia from beating by parylysing it - unable to expel the pathogens and debris

Question 30

Stomach

Answer 30

Very low pH

Question 31

Gall bladder

Answer 31

Bile - very toxic

Question 32

Digestive tracts

Answer 32

Digestive enzymes that degrades and kills

Question 33

Where are lysozymes are found

Answer 33

*Urine *Tears

Question 34

Where is cillia present?

Answer 34

Uterine tract and trachea

Question 35

Innate immunity (broad response)

Answer 35

SURFACE BARRIERS *Skin *Mucous membranes INTERNAL DEFENSES *Phagocytes - eats things *Natural killer cells - kills bacterial and cancer cells *Inflammatory molecules - causes blood flow *Antimicrobial peptides *Fever Cells are already ready to start acting, theyre at the site or can travel quickly to the site

Question 36

Adaptive immunity (specific, more powerful against one thing)

Answer 36

* B cells - memory cells, changes receptors to a specific pathogen and respond effectively * T cells that mediate cellular immunity - changes molecules they produce to respond to pathogen *Specific memory - can remember a specific infection and has defense in place for that if a second invasion occurs - we sometimes won't even know

Question 37

Cons of innate

Answer 37

-Limited specificity, cant tell diff between the pathogen -General response - innate memory, better response to a similar stimulus -Receptors dont change