8C MICROBES AND DISEASE

8C MICROBES AND DISEASE

MICROBES • What is a microbe?

• What are the three types of microbes? Give an example of each.

• What do we use microbes to make?

Top trumps

Micro-organisms The word MICRO means very small. (So you need a Microscope to see it!) http://www.cellsalive.com/howbig.ht m

Micro-organism Man!

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Micro-organisms

Micro-organisms Micro- very small Organism- a living thing.

So Micro-organisms are very small living things! N.B Viruses are often classed as microorganisms but technically they are NON-Living so call them Microbes instead! Microorganism man

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Microbe uses carousel • You will be assessed in this activity for AF2

Seven wonders of the microbe world

Bread mould experiment • You are going to look at mould growing on bread over 2 weeks.

Diseases • What is the scientific word for a microbe that causes disease?

• Name an example of a disease caused by a bacteria, virus and fungus?

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Bacteria The good the bad and the ugly!

Bacteria are small living single celled organisms that can come in good (beneficial) forms and bad (pathogenic) forms that cause disease.

Some different shapes of bacteria

Bacteria can double in number every 20 minutes!

The motility (movement) of some bacteria in culture. How fast!

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Pseudomonas aeruginosa

Good bacteria

Bacteria help to break down faeces (poo) in sewage works.

Bad bacteria in the mouth cause teeth to rot. Mouth bacteria

Mouth bacterium

MRSA- the bacterial superbug! Methicillin Resistant Staphylococcus aureus Methicillin (an antibiotic) WON’T Work to cure this infection!

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Bacteria

Cell wall Cytoplasm

Cell membrane Circle of DNA

Bacteria Cell wall Cytoplasm

Cell membrane Circle of DNA

Sometimes has a TAIL to help it swim

Structure of viruses

How viruses replicate inside cells

Examples of viruses

A T4 bacteriophage. This infects only bacterial cells, in this case only E. coli

The HIV virus. This attacks T4 lymphocytes. It is responsible for AIDS.

One sneeze can transmit many cold virus particles

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Bird flu virus

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Measles virus

Electron microscope picture of the measles virus

Boy with measles

Viruses cause

warts,

cold sores and verucae

Conjunctivitis

Foot and mouth disease is caused by a virus and is VERY infectious for cows From this

To this

Treatment of viral infections

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Virus Protein Coat Strand of DNA

Virus

Protein Coat

Strand of DNA

SMALLEST microbe

Also NOT technically alive…

Fungi

Why did the mushroom want to go out with the toadstool? Because he was a Fungi to be with!

Fungi are organisms that produce spores and come in the form of moulds, yeasts, mushrooms and toadstools.

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They also help things to rot and breakdown which is an essential process in the cycle of life.

Examples of fungi Mould growing a bread bun

There can be good forms of fungus (used to make bread/beer) and bad forms (Mould, Athletes foot and thrush).

Yeast cells budding

Mould and fungus causes things to breakdown

Fungus taking over

Athletes foot

Oral thrush

Thrush yeast cells

Fungi Cytoplasm

Cell membrane

Cell wall Nucleus

Starch granule

Vacuole

Fungi Cell wall Starch granule Vacuole Nucleus Cytoplasm

Cell membrane

BIGGEST microorganism

Sort the cards into if they are caused by a bacteria, virus or fungus

MICROBE BINGO

Similarities and differences • What do bacteria and viruses have in common?

• How are viruses different to bacteria and fungi?

Mould • What is mould?

• Why does food go mouldy?

• Name 5 different methods of stopping mould growth and explain why they stop it.

Mould investigation Aim: To investigate how to stop mould growing in gravy Variables Independent: Dependent: Control: Prediction

• http://www.ehow.com/how_6317533_makenutrient-agar-home.html

Gravy experiment results and conclusion

PEER ASSESSMENT FOR AF5

Yeast • What type of microbe is yeast?

• What do we use yeast to make?

• What types of respiration does yeast do?

Plan an investigation into one factor that affects yeast growth • You are going to put yeast, sugar, a drop of washing up liquid and warm water in a measuring cylinder • Choose one factor to change and investigate

Write the Aim, prediction, and variables

Aim: to observe yeast growth Time (mins)

Height of bubbles (mm)

The first line of defense • How can diseases be passed from one person to another?

• What is the bodies’ first line of defense to stop microbes entering?

Bread mould 2 week results

Match the defense mechanism to its use

The immune system • What is the immune system?

• Which cells defend us against disease?

• How do they defend us?

Video

Vaccination • Which cells produce antibodies?

• How do these cells respond when the body is infected?

• Why do vaccinations stop you getting ill again?

Video