Unit 4 Innate response

Question 1

Physical factors

Answer 1

• Skin: Epidermal
• Mucus Membranes: mucus membranes-> goblet cells, cilia, mucocillary escalator
• Normal flora: microbial antagonism

Question 2

Chemical factors

Answer 2

• Sweat-> makes cell hypertonic
• Sebum(oil)-> lack of water (dry)
• Gastric juices-> highly acidic
• Lactoferrin-> compete with siderophores to steal back nutrients (iron)
• Lysozyme-> gram (+), breaks apart sugar links in peptidoglycan
• Defensin peptides-> gram(-), disrupt out membrane (pores)

Question 3

Microbial antagonism

Answer 3

normal flora competes with transient flora

Question 4

Second line of defense (non specific) (phagocytes)

Answer 4

-Leukocytes-> phagocytes: neutrophils (first responders), macrophages (“big eater”), dendritic cells (APCs)

Question 5

phagocytosis

Answer 5

1. Chemotaxis
2. Adhesion
3. Engulfment
4. Fusion
5. Destruction

Question 6

Inflammation

Answer 6

1. Chemotaxis (chemical signaling recruitment of WBC’s)
2. Vasodilation (increasing blood flow and decreasing pressure)
3. Vessel Permeability (neutrophils leaves vessel to infected area)
4. Diapedesis (phagocyte migration)
5. Tissue repair

4 signs: redness, heat, pain, swelling (edema)

Question 7

Fever

Answer 7

• Systemic
• Phagocyte releases interlukin-1 (IL-1) causing hypothalamus to increase body temp
• 2 effects: body reactions speed up, and create an unfavorable temp for growth

Question 8

Interferon Response to Viral Infection

Answer 8

• Antiviral response
• Temporarily shuts down protein synthesis of neighboring cell
• Cell can recognize the long dsRNA and trigger interferon release