Download Unit 4 - Immunology and Public Health

Unit 4 Immunology and
Public Health
Unit 4 – Immunology and Public
Health
1. The Immune
System
a)Non-specific
defences
b)Specific cellular
defences
2. Infectious
Diseases and
immunity
a)Transmission and
control
b)Active
Immunisation and
Vaccination and
the evasion of
immune responses
Can you now ….
• Name some of the body’s
physical and chemical
defence barriers
• Explain the role of
epithelial cells in defence
• state when an inflammatory
response might occur
• describe the steps and cells
involved in the
inflammatory response
• describe the role and
process of phagocytosis
• describe the action of
natural killer (NK) cells
Quick Question
Complete the sentences below using the letters or
words in the box below:
A. Pathogen
B. Skin
C. Airways
D. Non-specific
E. Specific
F. Epithelial
1. A microbe that could cause us harm is known as a
A or Pathogen
_________
B or Skin
F or Epithelial
2. The ___________cells
that line our ______
and
C or airways
____________act
as a physical barrier to
pathogens.
D or non-specific
3. This is an example of _____________defence.
Quick Question
Match the immune factor to it’s function
1. Cytokine
A. Triggers the
inflammatory response.
2. Complement
antimicrobial proteins
B. Attract phagocytes
3. Phagocyte
C. Amplifies the immune
response.
4. Mast Cell
D. Engulfs pathogens.
Quick Question
Events in the inflammatory response are described below.
1 Clotting elements coagulate the blood
2 Phagocytes engulf pathogens
3 Blood capillaries dilate and increase in permeability
4 Healing
5 Mast cell releases cytokines and histamine
The sequence in which these events occur following is
A 2, 3, 1, 5, 4
B 2, 1, 3, 4, 5
C 5, 3, 2, 1, 4
D 5, 2, 1, 3, 4.
Questions
• Decide whether each of the following statements
is true or false. If it is false, correct the word in
bold to make it true. COPY THE CORRECT
SENTENCES IN YOUR JOTTER
1. The process of programmed cell death of a
pathogen infected cell is called phagocytosis
2. If white blood cells detect tissue damage, they
release cytokines which attract other white
blood cells to the site of injury
3. A phagocytes cytoplasm contains ribosomes full
of digestive enzymes
4. Following injury, mast cells in connective tissue
release histamine which causes vasodilation
5. Decreased capillary permeability occurs at an
infected site showing inflammation.
F
T
F
T
F
Quick Question
1. Which white blood cell secretes
histamine?
A. Phagocytes
B. Mast cells
C. Complement
D. Natural killer cells
Quick Question
2. Which of the following is NOT an affect
brought on by histamine at the site of an
infection?
A. Vasodilation
B. Clotting of blood
C. Attraction of phagocytes to site of
infection
D. Increased capillary permeability
Trick!! There are only 2 effects of histamine presence
Quick Question
3. Cytokines are secreted at the site of
infection. What effect does this have?
Antimicrobial protein /
clotting element is drawn to
the site of infection of the
skin (cut)
Quick Question
4. Which of the following describes the
action of phagocytes?
A. Stimulates inflammatory response
B. releases histamine
C. Causes programmed cell death
D. Engulfs pathogenic cell
Quick Question
5. Describe the action of Natural Killer
cells
Causes cell to self destruct
Extended Answer Question
• Describe non-specific defences that the
body uses to protect itself from
pathogens. (8 marks)
Higher Human Biology Revised 2013
1.
The skin prevents the entry of pathogens / is a physical barrier.
2.
Epithelial cells (in cavity linings) produce (protective chemical) secretions
3.
Description of one non-specific defence e.g. mucus in windpipe / acid in stomach /
lysozyme or anti-bacterial substances in tears / coughing or sneezing / blood clotting
4.
The inflammatory response is caused by the release of histamine from mast cells
5.
Vasodilation / increased capillary permeability / increased blood flow (occurs)
6.
Increased blood flow / secretion of cytokines results in the accumulation of phagocytes
7.
It also results in the delivery of antimicrobial proteins / clotting elements to the site
8.
Phagocytes recognise surface antigens or protein markers on pathogens
9.
They then destroy the pathogen by engulfing it / by phagocytosis
10.
Natural killer (NK) cells induce the pathogen to destroy itself / apoptosis
11.
(The NK cells cause) the pathogen to produce digestive / self-destructive enzymes
12.
Phagocytes / NK cells release cytokines that stimulates the (specific) immune response
8 marks