immune system and viruses

Question 1

immune responses

Answer 1

• Nonspecific - barriers (i.e. skin), inflammatory response\
• Specific - cell + antibody mediated immunity

Question 2

first line of defense

Answer 2

Nonspecific barriers (i.e. mucus/bacteria in mouth/macrophages)

Question 3

Second line of defense

Answer 3

Second line of defense - Nonspecific inflammatory response
- If pathogen gets into the body - histamines released from injured body cells that cause area to swell
- Capillaries will dilate brining more blood with white blood cells (phagocytes) to destroy pathogen

Question 4

Third Line of Defense

Answer 4

Third Line of Defense - Specific immune response
- Triggered by antigens
- Antigens - any foreign substance that can stimulate an immune response (marker proteins on bacteria/virus/parasites)
- Antibodies - large Y-shaped proteins used to identify + neutralize foreign objects
- Immune system responds to antigens by increasing number of cells that can attach to invaders directly or that produce antibodies to tag them for destruction
- Tagged pathogens will signal T and B cells to destroy and get rid of it

Question 5

allergies

Answer 5

Allergies - result from immune cells that over-respond to non-pathogenic substances
- Allergens (pollen/dust/etc.) can trigger inflammatory responses and release histamines which cause sneezing/itching/etc.

Question 6

virus overview

Answer 6

• Nonliving
• Specific to organism they attack and will use cell organelles to carry out their job (hijacks cell)
• Bacteriophage - virus that infects a bacteria
• Structure
  
  • Non-cellular infectious agent
  • Contains a protein coat called the capsid
  • Has genetic material (DNA/RNA)

Question 7

immune system overview

Answer 7

Body’s defense against disease causing agents, malfunctioning cells, and foreign particles
- Innate immunity - effective from the time you are born
- Acquired immunity -developed over time from exposure to pathogens and vaccines

Question 8

virus reproduction

Answer 8

1. Attachment - virus attaches to receptors on host cell
2. Penetration - virus particle/genetic material crosses cell membrane of a host cell and enters cytoplasm
3. Replication + Synthesis - viral DNA/RNA replicates and makes new viral parts
4. Assembly - new viruses are made inside host cell
5. Release - particles are released from host cell and can cause cell death

Question 9

lytic cycle

Answer 9

Steps of attachment occur quickly until cell bursts open and new viruses are spread to surrounding cells