Immune System

Question 1

What are the 4 biological organisms that cause disease?

Answer 1

• viruses
• parasites
• bacteria
• fungus

(-prions) → not a lot known about them

Question 2

What are Viruses?

Answer 2

• they are nonliving biological agents that invade cells
• they consist of a nucleic core, containing either DNA or RNA protein coat (Caspid)
• they enter the body via respiratory, digestive, insects, or sexual contact

Question 3

What are Bacteria?

Answer 3

• they are classified as living Prokaryotess (no nucleus)
• enter the body through the respiratory system, G I system, urinary system or abrasions in the skin
• bacteria are manipulated by antibiotics - inhibit protein synthesis

Question 4

What is Bacterial Resistance?

Answer 4

• due to heavy use of antibiotics (often when they are not useful in viral infections? and from black marketeers have resulted in antibiotic-resistant bacteria
• resistance is caused by bacteria that survive or mutate to become stronger to antibiotics
• enters body through holes in body (nose, ear, cuts, mouth)

Question 5

What are Fungi?

Answer 5

• classified as a eukaryote (has a nucleus)
• oral thrush is transmitted by poor oral hygiene, prolonged use of steroids, inhaled steroids, and false teeth
• through contact from an infected person can come athlete’s foot and ringworm
• enters body; often found ON your body

Question 6

What are Parasites?

Answer 6

• protists, like malaria
• roundworms, like Racoon Worm
• flatworms, such as tapeworms are multicellular heterotrophs that enter the body in a variety of ways
• Enter body through eating, (tapeworm-sushi) ingesting, burrow through skin

Question 7

What are Prions?

Answer 7

• naked proteins → don’t have a coat
  ex.) mad cow disease

Question 8

Attack From Inside

Answer 8

• cells are packages of macromolecules
• no cell wall
• traded mobility for susceptibility
• animals must defend themselves against invaders like:
  → viruses:
  HIV, flu, cold, measles, chicken pox, SARS
  → bacteria:
  pneumonia, meningitis, tuberculosis
  → fungi:
  yeast (athlete’s foot)
  → protists + worms (especially nematodes_
  amoeba, Lyme disease, malaria
  → defied against abnormal body cells = cancers

Question 9

Physical / Chemical Defenses

Answer 9

• non-specific defense
  external barrier
• external barrier
  epithelial cells + mucus membranes
  skin, respiratory system, digestive system, uro-genital tract
• lining of trachea → celiated cells + mucus secreting cells

Question 10

Skin

Answer 10

thick, dead cells contain a protein called KERATIN (waterproof layer that protects underlying tissues)

Question 11

Stomach Lining

Answer 11

• produces hydrochloric acid that destroys digested bacteria

Question 12

Tears + Salva

Answer 12

• contains lysozome that dissolves the cell wall of bacteria, killing them

Question 13

Respiratory System

Answer 13

• produces mucus which has antimicrobial properties

Question 14

2nd Line of Defense: Internal, Broad Range Patrol

Answer 14

1. inflammatory response
2. pyrogens
3. interferons
4. complement

Question 15

Inflammatory Response

Answer 15

• characterized by swelling, redness, and pain
• injured tissue releases chemical substances that attract macrophages and neutrophils
• histamine- stimulates the arterioles in the injured tissue to dilate, causing the capillary networks to swell with blood
• prostaglandin- pain-causing chemical released

Question 16

Pyrogens

Answer 16

• molecules released primarily by macrophages that have been exposed to bacteria
• travel to the hypothalamus in the brain to turn the heat up in the body (fever)
  → reduces bacterial replication
  → increases metabolism + accelerates phagocytosis

Question 17

Interferons

Answer 17

• released from cells infected by viruses
• diffuse away from the cite of infection through the interstitial tissue and bind to the receptors on the plasma membranes of non-infected body cells
• inhabit viruses from replicating + spreading

Question 18

Complement Proteins

Answer 18

• they complement the action of antibodies
• form the membrane- attack complex causing the bacterial cell to swell, burst, and die
• they also produce chemical attractions, drawing phagocytic white blood cells to the cite of infection

Question 19

Leukocyte Phagocytic White Blood Cells

Answer 19

• attracted by chemical signals released by damaged cells
  → enter infested tissue, engulf + ingest microbes

Question 20

Neutrophils

Answer 20

• most abundance white blood cell (70%)
• 3 day life span

Question 21

Macrophages

Answer 21

• “big eater,” long-licked

Question 22

3rd Line of Defense

Answer 22

• the cells of the immune system selectively target foreign substances and foreign organisms→ specific
• identifies what belongs in the body and what does not:
  antigens
  T- Cells
  B- Cells
  Antibodies

Question 23

What are Antigens?

Answer 23

• they are antibody-generating substances
• viruses, bacteria, fungi, parasites, and protozoan contain large molecular proteins or polysaccharides that are antigens

Question 24

What are T-Cells?

Answer 24

• matures in thymus
• they attack foreign cells directly (interact directly)
  → cytotoxic T-(killer) destroy body cells
  → helper T-enhance the immune system
  → suppressor T- turn of the immune system when the antigen dissappears
  → memory T- remember past viruses + protects against them / kills viruses

Question 25

What are B-Cells?

Answer 25

- mature + differentiate in the bone marrow - provide humoral immunity - produce antibodies - proteins that eliminate antigens, bacterial and/or bacterial toxins -make antibodies that float around in fluids

Question 26

Types of Immunity

Answer 26

- Humoral Immunity - Cell-Mediated Immunity - Passive Immunity - Active Immunity

Question 27

Developing a Strong Immune System

Answer 27

- the best way to develop an immune system is to use it when young - children who are sheltered from normal childhood illnesses develop more asthma and allergies - breast milk from the mother contains antibodies that can be passed on to the child

Question 28

Humoral Immunity

Answer 28

- B Cells - B cells form memory cells + plasma cells that produce antibodies to agents

Question 29

Cell-Mediated Immunity

Answer 29

- T Cells - T Cells differentiate into memory cells, cytotoxic cells, suppressor cells + helper cells that attack the antigen directly

Question 30

Passive Immunity

Answer 30

- obtaining antibodies from another individual - maternal immunity → antibodies pass from mother to baby across placenta or in mother's milk → critical role of breastfeeding in infant health → mother is creating antibodies against pathogens; baby is being exposed to injection - protected for a short period of time

Question 31

Active Immunity

Answer 31

- vaccination - actively produces memory T + B cells that protect a person against future infection - contain inactivated or weaken viruses - always protected