1. PATHOGENS
PATHOGEN, BACTERIA, VIRUS, TOXIN, INFECTIOUS

2. By the end of the lesson I:
Objectives
By the end of the lesson I:
Know a PATHOGEN is a micro-organism that causes an infectious disease
Know pathogens reproduce before they make enough toxins to make you feel ill
Know what Semmelweiss discovered about the transfer of infection (Grade C)
Know why it took so long for his ideas to be accepted
(Grade A)
Know how to use aseptic technique

3. What effect does isotonic drinks have on your body?
Starter
What effect does isotonic drinks have on your body?
AQA
Digilist
Human Biology
B1a.3 Recovering Rates and B1a.6 High Energy Drinks

4. How do pathogens affect your body?
Infectious disease
Are worldwide and range from the common cold to influenza and ebola. It is caused by a micro-organism that enters and attacks your body. People can easily transmit the pathogen from one person to the next.
How do pathogens affect your body?
Bacteria and virus cause disease once in your body. Bacteria split into two and produce toxins (poisons) that affect your body, sometimes directly damaging your cells.
Virus rarely produce toxins. Instead they damage or destroy your cells as they take them over to reproduce.

5. What are common disease symptoms?
High temperature
Headache
Rash
Symptoms are produced;
As an affect of the toxins in your body
A reaction of your body to respond to the damage/toxin

6. WHAT ARE YOU TRYING TO FIND OUT? WHAT DO YOU EXPECT TO FIND OUT?
I know HOW TO USE ASEPTIC TECHNIQUE
How do we effect change?
We are going to grow some yeast…..
AND THEN KILL IT!
Using ASEPTIC TECHNIQUE infect a petri dish with a yeast solution.
Wait for the solution to slightly dry (perhaps 1hour)
Place a full drop of antiseptic onto the centre of the agar plate.
Incubate for 24-48hours.
WHAT ARE YOU TRYING TO FIND OUT?
WHAT DO YOU EXPECT TO FIND OUT?

7. Are all micro-organisms pathogens?
I know a PATHOGEN is a micro-organism that causes an infectious disease and that pathogens reproduce before they make enough toxins to make you feel ill
Are all micro-organisms pathogens?
What is a pathogen?
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How do pathogens harm your body?

8. Not all bacteria cause disease but all virus' do
I know a PATHOGEN is a micro-organism that causes an infectious disease and that pathogens reproduce before they make enough toxins to make you feel ill
BACTERIA- single celled organisms
VIRUS
50 times bigger
50 times smaller
Can be seen by an ordinary light microscope
Cannot be seen by an ordinary light microscope. Can be seen by an electron microscope.
Reproduces by dividing in two
Reproduces by taking over and using the reproductive structures of another cell.
Can be killed buy antibiotics because it kills or inhibits the bacteria’s ability to divide and reproduce
Cannot be killed by antibiotics
Photo credit: © 2006 Jupiterimages Corporation
Not all bacteria cause disease but all virus' do

9. The structure of bacteria
I know a PATHOGEN is a micro-organism that causes an infectious disease and that pathogens reproduce before they make enough toxins to make you feel ill
The structure of bacteria
Cell membrane
Slime capsule
Cell wall
Cytoplasm
Photo credit: © 2006 Jupiterimages Corporation
Genetic material

10. I know a PATHOGEN is a micro-organism that causes an infectious disease and that pathogens reproduce before they make enough toxins to make you feel ill
Types of bacteria

11. I know a PATHOGEN is a micro-organism that causes an infectious disease and that pathogens reproduce before they make enough toxins to make you feel ill
The structure of virus
Protein coat
Genetic material
Photo credit: © 2006 Jupiterimages Corporation

12. did nothing but complain!
I know what Semmelweiss discovered about the transfer of infection (Grade C) and why it took so long for his ideas to be accepted (Grade A)
Use your text
Ignaz Semmelweiss
did nothing but complain!
Photo credit: © 2006 Jupiterimages Corporation
5 marks

13. I know what Semmelweiss discovered about the transfer of infection (Grade C) and why it took so long for his ideas to be accepted (Grade A) A
Semmelweiss died in 1865. B
His friend Dr Jakob Kolletschka cut himself while dissecting a dead body and died of the same symptoms as ‘child bed fever’ C
In hospitals where doctors took his advice, death rates from ‘child bed fever’ fell quickly. D
In the 1870s Robert Koch proved that bacteria can cause disease. E
Semmelweiss realised that the medical students were dissecting dead bodies on the same day they were working in the labour ward. The student midwives never dissected dead bodies. F
Semmelweiss reported his findings to other doctors but he could not prove why hand washing worked because scientists knew little about bacteria and had not proved that they caused disease. G
Today, Semmelweiss is widely considered to be the father of infection control. One of the main ways we prevent the spread of MRSA is proper hand washing. H
In the 1840s a Hungarian doctor, Ignaz Semmelweiss, noticed that women in the labour ward staffed by medical students were much more likely to die of ‘child bed fever’ than those in the labour ward staffed by student midwives. I
Semmelweiss ordered his students to wash their hands in an antiseptic solution. Unfortunately the solution damaged their skin. J
In hospitals where doctors did not agree, death rates stayed high.
Photo credit: © 2006 Jupiterimages Corporation

14. plenary

15. By the end of the lesson I:
Objectives
By the end of the lesson I:
Know a PATHOGEN is a micro-organism that causes an infectious disease
Know pathogens reproduce before they make enough toxins to make you feel ill
Know what Semmelweiss discovered about the transfer of infection (Grade C)
Know why it took so long for his ideas to be accepted
(Grade A)
Know how to use aseptic technique