b2 – lesson 1 keeping healthy

B2 – Lesson 1 Keeping Healthy

• Brainstorm how we get ill

How do we get ill?

Infections - Objectives and Outcomes

At the end of the lesson students will be able to:

•State 3 types of micro-organism (D)

•Explain why you get symptoms when you have an infection or disease (C)

•Discuss the health risks associated with infections (B)

The Importance of Hygiene

Why should you wash your hands after using the toilet?

What are Pathogens?

Micro organisms that cause disease.

What are What are Microbes?Microbes?

• Living things are called __ __ __ __ __ __ __ __ __ .

• Tiny organisms can be made of only __ __ __ cell.

• We call them __ __ __ __ __ organisms.

• Micro-organisms are some times called microbes for short.

• We can not see them with our eyes…

What are What are Microbes?Microbes?

Do we use a Do we use a microscopemicroscope or a or a

telescopetelescope to see them? to see them?

MicroscopeMicroscope

TelescopeTelescope

What What Diseases do Diseases do you know you know

of?of?

What causes What causes Disease?Disease?

There are three types of microbes:

Different Types of Microbes

bacteria viruses fungi

microbes

What are microorganisms?

• Fungi Small...

• Bacteria ...smaller...

• Viruses ...smallest!

Why do bacteria and viruses make you ill?

Symptoms of disease are caused by damage done to cells or by toxins they make.

In suitable conditions micro-organisms can reproduce rapidly into large numbers!

Which is not a microbe

A, Fungus

B, Bacteria

C, Virus

D, Organ

What do you call a disease causing microbe?

A, Antigen

B, Pathogen

C, Capsicum

D, Pathostem

What does not cause symptoms of disease

A, Damage to Cells

B, Toxins

C, Rapid reproduction of the pathogen

D, High temperature

Microbe Size Structure How Reproduce

Picture

Viruses

Bacteria

Fungi

5 minute breather

• Video of TV ad campaign for Sti’s

http://www.youtube.com/watch?v=HzmWaYHHRPA

True or False?

1. A person can have an STI and not know it

2. Once you have had an STI and have been cured, you can’t get it again

3. A pregnant woman who has an STI can pass it on to her baby

4. Most STIs go away without treatment, if people wait long enough

5. STIs that aren’t cured early can cause sterility

6. Birth control pills offer protection from STIs

7. Condoms can help prevent the spread of STIs

8. If you know your partner, you can’t get an STI

9. A sexually active woman should get an annual pap test from her doctor

10. Chlamydia is a type of STI

11. Only young people can get STI

What is under your fingernail??

• There are lots of things in the world around us that you cannot see with your own eyes.

• There are living things made of many cells

• And there are living things made

of only one cell

Microbes are micro organisms that are too small to be seen. A pathogen is a microbe that can cause diseases if it enters the body:

Micro-bugs vs Bacteria

Microbug on a Human hair BacteriaHuman hair

Is that as small as microbes get?

Nope: Viruses are even smaller

Lesson 1: Infectious diseases

Copy and complete:

Infections are caused by some ____________ that invade the body. Microorganisms are ______, ________ and _______.

When disease microorganisms get inside your body, they _______ very quickly. This causes _______ - the ill feelings. Symptoms can be caused by

1. ______________________

2.______________________

Infect nearby cells and repeat the process.

Use the cell contents to replicate (form thousands of identical copies)

Viruses are taken into cells in the body

Damage the cell as they burst out and

Virus Reproduction - What’s the Order?

1. Viruses are taken into cells in the body

2. Use the cell contents to replicate (form thousands of identical copies)

3. Damage the cell as they burst out and

4. Infect nearby cells and repeat the process.

Virus Reproduction - What’s the Order?

B2 lesson 2Microbe attack

LO: to know what parts of your body stop micro-organisms getting in [C] and how the body fights

off micro-organisms when they are inside [B]

8C Defence!

Fighting diseaseIf microbes do enter our body they need to be neutralised or killed. This is done by WHITE BLOOD CELLS:

White blood cells do 3 things:

1) They eat the microbe (phagocytosis)

2) They produce antibodies to neutralise the microbe

3) The produce antitoxins to neutralise the poisons produced by microbes

Producing antibodies

Step 1: The white blood cell “sees” the antigen (microbe)

Step 2: The cell produces antibodies to “fit” the antigen

Step 3: The antibodies fit onto the antigens and cause them to “clump”

Step 4: The antigens are “eaten” by the white blood cells

You’re going down

Brainpop – Immune system

8C Immunity

Quick Questions

Red blood cells carrying…….........?White blood cells ready to fight…….......?

Story Board Rules

Task : in pairs draw a story board that illustrates the two methods white blood cells use to fight infection

• 5 mins brainstorm and discuss• 20 mins• Must contain GOOD science• Must use keywords – antigen, antibodies, immune, phagocytosis, • Pages 92-93

BINGO• Antigen• Infection• Antibody• White blood cell• Immunity• Fungi• Phagocytosis• Engulf• Red blood cell• Memory cell• Lymph nodes• Pathogen• Virus• Bacteria• Microorganism

In GCSE science exams they like to test your MATHS skills...Calculate the population growth of

microorganisms given appropriate data

EXAMPLE:-

Revisium biologus is a bacterium that reproduces every 20 minutes. If 10 R.biologus bacteria are left for 2 hours, how many bacteria will there be at the end of this period?

There are some simple steps to work this out...

Immune SystemLO: to understand the different roles white blood cells can play in

fighting off disease [C] calculate population growth of microorganisms [B] explain why white blood cells create

antibodies [A] (STS: 2)

Mix and match

• I cause thrush• I provide antibodies• I cause AIDS• I am smaller than fungi but

bigger than a virus• I only kill bacteria and fungi

mini test

• 6 = A*

• 5 = A

• 4 = B

• 3 = C

• 2 = D

What is a pathogen?

C

A disease causing microbeA

A change in the environment

B

Fungi, Bacteria and Viruses

D

A type of medicine

Which of these is NOT a first line of defence against

disease?

A B

C D

Mucus

White blood cells

Skin

Stomach acid

Which picture shows a virus?

A B

A low number of species which are adapted to survive in low

oxygen concentrations

C D

What do ALL microbes need for optimum growth?

A B

C D

Warmth

Nutrients

Carbon dioxide

Oxygen

Moisture

Warmth

Moisture

Alkali

Nutrients

Warmth

Moisture

Nutrients

What does ‘phagocytosis’ mean?

B

The immune system

C

A WBC engulfing (eating) a microbe

A

Fossilisation

D

To get better quickly after

infection

Fighting diseaseIf microbes do enter our body they need to be neutralised or killed. This is done by WHITE BLOOD CELLS:

White blood cells do 3 things:

1) They eat the microbe (phagocytosis)

2) They produce antibodies to neutralise the microbe

3) The produce antitoxins to neutralise the poisons produced by microbes

Producing antibodies

Step 1: The white blood cell “sees” the antigen (microbe)

Step 2: The cell produces antibodies to “fit” the antigen

Step 3: The antibodies fit onto the antigens and cause them to “clump”

Step 4: The antigens are “eaten” by the white blood cells

You’re going down

Specific antibodies

Antibodies are specific – they will only neutralise the microbe they have been made for.

Once we have made an antibody to recognise a particular microbe, ‘memory cells’ can make that antibody again very

quickly, therefore protecting against that microbe in the future - IMMUNITY

fighting off infectionOutcomes: produce a story board that explains how our

white blood cells create antibodies to fight off infection.

Success Criteria:C – create a labelled diagram for each stage

B – explain in words what is happening

A – use 8 scientific words in your explanationStages (not in correct order)

•Antigens eaten•Antigens seen

•Produces antibodies•Clump together

20 minutes

EXTENSION•Draw a diagram to represent

WBC making antitoxins to neutralise the poisons

produced by microbes

Key Words

White blood cell Antitoxins

Microbe Pathogen

Antibodies Phagocytosis

Antigen Immune

Engulf Memory Cells

Specific Neutralised

8C Immunity

Worksheet - Bacteria and viruses can grow EXPONENTIALLY ...

reproduction period 1


3

4



EXAMPLE:-



Exam Question (hard)

3 marks – pick from the following

• number of bacteria after 2 hours is 12 800 (or 1.28 x 104), which is a sufficient number to cause food poisoning

• idea that if conditions were not optimum the actual number may be lower than this

• idea that not enough data/evidence/information, or would need to measure more things, to conclude that person will definitely get food poisoning

• idea of immune response against bacteria or toxins / acid in stomach destroying bacteria or toxins

Graphs – yuck!(but a popular question)

Discuss with your partner what I show.

Con

cent

ratio

n of

ant

ibod

ies

in

bloo

d

0 10 20 30 40 50 60 70 80 90Time (days)

1st exposure to MO

2nd exposure to the same MO

10 days

25 days

End of lesson quiz

Turn to the back of your book and put 1 to 5 in the margin.

The questions will pop up, answer them as quickly as possible.

Quiz questions

1. Name the 3 main types of microbes

2. Which organ uses acid to kill microbes?

3. What do white blood cells make to fight microbes?

4. What P is a disease causing microbe?

5. What does engulf mean?

5 correct A

4 correct B

2-3 correct C

1 correct D

Drug TestingLO To know the main stages of drug testing and the ethical

and validity issues of being in a drugs trial

STARTER

If you were ill and you were asked to

take part in a trial for a new drug what

questions would you ask before deciding

if you would be involved.write three questions

spiders on drugs video

Drug Testing Leaflet

Create a leaflet that is all about testing new drugs.

On it describe the 3 main stages of testing a new drug

On your leaflet explain the following key terms in clinical trials and

why

they are important:

a. double blind trial

b. blind trial

c. a placebo.

d. random groups

e. the control group

What is a pathogen?

C

A disease causing microbeA

A change in the environment

B

Fungi, Bacteria and Viruses that

do not cause disease

D

A type of medicine

What is a double blind trial?

A B

C D

Even the scientist

don’t know who got the

real drug

The patients are testing eye drops

The scientists know who

gets the real drug

Both the scientists and the patients know the treatment

being used

The patients don’t know if they have been given the real

drug

What is a blind trial?

A B

A low number of species which are adapted to survive in low

oxygen concentrations

C D

The trial has psychological

effects

Even the scientist

don’t know

who got the

real drug

The patients are testing eye drops

What is a placebo?

An 90’s indie bandA B

C DA fake

treatment to eliminate

psychological effects

A real test drug used in medical

trials

A type of white

blood cell

What is an open-label trial?

B

C

An unethical trial

A fake treatment to

eliminate psychological

effects

A

D

Both the scientists and the patients

know the treatment being used

Even the scientist don’t know who got

the real drug

Heart DiseaseLO - To know the risk factors associated

with heart disease.

Starter

You are part of a double blind trial for a new drug and you are given the placebo. Explain what this means in words a year 7 would understand.

Task: create an informative poster for use in a doctors surgery on how to reduce your risk of heart disease.

• Include information on:– Diet– Smoking– Drugs– Stress– Alcohol– Epidemiological Studies - extension

HEART DISEASE (T or F)• Heart attacks are common in the UK • Only men have heart attacks.• Young people don’t have heart attacks.• Smoking increases your risk of heart attack.• Heart attacks happen when arteries to the heart are

blocked.• Heart attacks are always fatal.• When you have a heart attack, some of your muscle dies.• Heart muscle dies when it doesn’t get oxygen.• Any fat in your diet is harmful.• Being overweight puts a strain on your heart.

Starter - Which is riskier?

Nuclear Power or Peanut Butter?

Calculating Microbial Growth and Antimicrobial Resistance

HEART DISEASE (T or F)• Heart attacks are common in the UK • Only men have heart attacks.• Young people don’t have heart attacks.• Smoking increases your risk of heart attack.• Heart attacks happen when arteries to the heart are

blocked.• Heart attacks are always fatal.• When you have a heart attack, some of your muscle dies.• Heart muscle dies when it doesn’t get oxygen.• Any fat in your diet is harmful.• Being overweight puts a strain on your heart.

Worksheet - Bacteria and Viruses can grow EXPONENTIALLY ...



3

4



EXAMPLE:-



• Step 1: work out how many minutes there are!

2 hours = 120 minutes• Step 2: work out how many reproduction periods that will be!

120 minutes÷20 minutes = 6 reproduction periods • Step 3: work out the number of bacteria after the first reproduction period

10 R.biologus (at start) x 2 = 20 R.biologus• Step 4: work out the number of bacteria you’d have after the second

reproduction period

20 R.biologus x 2 = 40

Step 5: keep going until you have done all 6 reproduction periods!

EXAMPLE:-


You could use a table...

Reproduction period Number of bacteria

1 10 R.biologus x 2 = 20




5 160 R.biologus x 2 = 320

6 320 R.biologus x 2 = 640 <<< ANSWER!!!

EXAMPLE:-


Exam practice 1

Huguntis flavis is a bacterium that reproduces every 30 minutes. If 5 H.flavis bacteria are left for 3 hours, how many bacteria will there be at the end of this period?

Exam practice 2

Vicitus diosilus is a bacterium that reproduces every 10 minutes. If 12 V.diosilus bacteria are left for 40 minutes, how many bacteria will there be at the end of this period?

EXTENSION - Exam practice 3

Krispeecremus donutus is a bacterium that reproduces every 45 minutes. If 15 K.donutus bacteria are left for 4.5 hours, how many bacteria will there be at the end of this period?

Antibiotic Resistance

Superbug Video

15 mins to make a postcard for a doctors surgery on antibiotic

resistance

Fungi N

eeds

Bacteria

Full Course

How it works

Circulation and the HeartLO - To know the role of the heart and how it works

Starter

You are part of an open label trial for a new drug. No one is given a placebo. Explain what this means in words a year 7 would understand. Give an ethical reason why open label trials are used in developing new drugs.

The heart

This section of the system including the right side of the heart, deals with the deoxygenated blood.

This section of the system including the left side of the heart, deals with the oxygenated blood.

Lungs

Body cells

Our circulatory system is in two parts. It is in fact called a double circulatory system.

Double circulatory system

Blood from the lungs

pulmonary vein

Atrium


Blood squeezed through valves into…


…the ventricle

Blood from the lungs…

…goes to the body

Aorta

pulmonary vein

Blood from the body

Vena cava

Atrium

…to the lungs

Aorta

Vena cava

Copy pictureAorta

Vena Cava

The human circulatory system

Video and Dissection

blood

valve

These valves are rather like doors that only open in one direction.

Valves

The main valves in the heart

The Circulatory System

There are 3 types of blood vessels

ArteriesVeinsCapillaries

Blood vessels

• This is a system of tubes that transport blood around the body.

• Vein – carries blood towards the heart

• Artery – carries blood away from the heart

• Capillaries – really small blood vessels

Arteries and VeinsArtery

Vein

thin outer wall

thick layer of muscle and elastic fibres

thick outer layer

thin layer of muscle and elastic fibres

Arteries• These carry blood AWAY from the heart

(Think Arteries Away = AA)

• They are buried deep in the body

• They carry oxygen rich blood (except for the pulmonary artery!)

Veins• These carry blood IN to the heart

• (Think veINs=IN)

• They carry oxygen poor blood (except for the pulmonary vein!)

Capillaries

• These carry blood to the cells

• They are narrow vessels running throughout the body

• They carry oxygen rich blood from the arteries, past the cells. The oxygen poor blood is then carried to the veins.

Can you label the blood vessels?

1. Artery, capillary, vein,

2. small lumen, large lumen, very small lumen

3. Single cell wall, thick elastic wall, thin wall

Plenary - The Circulatory System


Which of these blood vessels:1. Takes blood away from the heart?2. Carries oxygenated blood?3. Contains blood under high pressure?4. Is only 1 cell thick?5. Contains valves?

What is the effect of alcohol on the heart rate of Daphnia?

Starter – label your Daphnia diagram

What is your independent variable?

What is your dependent variable?

What variables will you keep the same?

Why?

What will you do to make your results reliable (repeats)?

What will you do to make your results accurate (measurements)?

How many results will you need to collect to make the investigation valid?

What is the effect of alcohol on people?

What effect do you think the alcohol will

have on the heart beat of Daphnia?

What equipment will you need?

What is the effect of alcohol on Daphnia?

Planning

My independent variable that I will change is ______ .

My dependent variable that I will measure is _______.

To make it a fair test I will keep ______ , __________, _____________ , and __________ the same.

The equipment that I will need is _________________

______________________________________________________________________________________

Method

I predict that ________________________________

____________________________________________________________________________________

Results

Alcohol % Attempt 1

Attempt 2

Attempt 3

average

ConclusionAs the amount of alcohol in the water increased ________________________________________________When there was the most alcohol in the water _________________________________________________When there was the least alcohol in the water _________________________________________________My conclusion about the effect of alcohol on Daphnia is ________________________________________________________________________________________________________________________________I think in humans alcohol __________________________________________________________________

Normal dietDrunk plenty

of water

Has been exercising but not drunk anything

Who’s urine? MATCH UP!

Learning Objective

To be able to explain how our bodies control water content.

Title - Homeostasis

Learning Outcome

• Homeostasis involves making sure that our bodies have the correct levels of 4 key things.

• Can you name two of them?

What is Homeostasis?

• Homeostasis makes sure our body has the correct levels of;

Temperature

Carbon dioxide

OxygenWater

Homeostasis involves maintaining a

constant environment in the body

In Out

BreathSweatFaecesUrine

Food and drinkWater made in respiration

B2 : How does the body control water balance?

Our bodies need a balanced water level to keep the internal concentration of our cells at the correct level

for them to work properly.

The kidneys

Kidneys do two main jobs:

1. Remove waste urea from the blood.

2. Keep a balance of other chemicals in the blood – including water.

How kidneys work

Filtering all small molecules from the blood.

Reabsorbing all of the glucose.

Reabsorbing as much salt as the body needs.

Reabsorbing as much water as the body needs.

Excreting the remaining urea, excess water and salt as urine, which is stored in the bladder.

Water balance

The concentration of blood plasma is monitored as it passes through the brain.

If the blood is too dilute then kidneys excrete more water in the urine.

If the blood is too concentrated then kidneys excrete less water in the urine.

The amount of water in the blood depends on: external temperature, exercise, intake of fluids and salts.

ADH and water balance.

The concentration of urine is controlled by a hormone called ADH (anti-diuretic hormone).

It is released into the bloodstream by the pituitary gland.

Normal blood concentration

Blood too concentrated – detected in brain

ADH secreted by pituitary gland

ADH causes kidneys to reabsorb more water to blood

Normal blood concentration

Blood too dilute – detected in brain

ADH not secreted by pituitary gland

kidneys reabsorb less water to blood

Water Balance

Outcomes: create a think board on homeostasis and water balance.

Which hormone controls water content in the body?

Where is it released from?

What 3 main things can effect the concentration of urine?

(D)

How do the Kidneys help keep water in the body balanced?

(C)

Draw a flow diagram of how the concentration of urine is controlled by a hormone

(B)

Explain in as much detail as possible (use as many science key words as you can) how Alcohol and Ecstasy affect ADH production

(A)

TITLE: Controlling Water Content

True/False Quiz!

• Your urine is always the same.• The pituitary gland monitors blood plasma.• Homeostasis maintains a constant internal

environment.• The liver helps balance water and waste in the

body.• Alcohol suppresses ADH production.• Ecstasy increases ADH production.

FALSE

TRUETRUE

FALSE

TRUE

TRUE

Dehydration

Drowning

Which is the odd one out?

bacteria

virus

fungus

B2 past EXAM questions!

• I will be round to mark them as you go ready to put into your progress folder.

ALL must do 2 exam questions

SOME will do more so can pick their highest grade for progress folder

FEW will do all exam questions for a PRIZE!

Testing Urine• Draw the following table in your books neatly.

• Test the 3 urine samples for protein and for sugar using the equipment available.

• EXTENSION: explain in as much detail as possible what homeostasis is and how water content is controlled in the body.

Sample Protein Sugar

A

B

C

Drug Trials• Outcomes: create a Powerpoint on the use of drug

trials in medical science.

Include information on the following:- Laboratory testing on human cells [C]- Laboratory testing on animals [C-B]- Human clinical trials [A]

- ‘blind trails’ (you’ll need to know what a placebo is)- ‘double blind trials’ - ‘open label trials’

Starter – Describe what this image below shows

An antibody can only bind to a specific type of antigen

Describe the peer review process and explain why it is important

• Scientists in the same field check the validity of research

• Work is only published if it is found to be trustworthy /reliable

• Important because only trustworthy/reliable science is published

• Information will not mislead the public

How will alcohol in the beer affect the amount of ADH release into Damon’s bloodstream and how

will this affect the volume of Damon’s urine?

• Alcohol suppresses ADH production

• Damon will have a greater volume of urine

Why is there no vaccine for the HIV virus?

• HIV does not have a protein coat so cannot be recognised by antibodies

• HIV seeks out and actively attacks WBCs therefore weakening the immune response

• HIV makes your own body start to destroy its own WBCs

Arteries and VeinsArtery

Vein

thin outer wall

thick layer of muscle and elastic fibres

thick outer layer

thin layer of muscle and elastic fibres

Arteries• These carry blood AWAY from the heart

(Think Arteries Away = AA)

• They are buried deep in the body

• They carry oxygen rich blood (except for the pulmonary artery!)

Veins• These carry blood IN to the heart

• (Think veINs=IN)

• They carry oxygen poor blood (except for the pulmonary vein!)

Capillaries

• These carry blood to the cells

• They are narrow vessels running throughout the body

• They carry oxygen rich blood from the arteries, past the cells. The oxygen poor blood is then carried to the veins.

Can you label the blood vessels?

1. Artery, capillary, vein, 2. small lumen, large lumen, very small lumen3. Single cell wall, thick elastic wall, thin wall

Antibiotic Resistance

Superbug Video

15 mins to make a postcard for a doctors surgery on antibiotic

resistance

Fungi Needs

Bacteria F

ull Course

How it works

Wash hands

Plenary - The Circulatory System


Which of these blood vessels:1. Takes blood away from the heart?2. Carries oxygenated blood?3. Contains blood under high pressure?4. Is only 1 cell thick?5. Contains valves?

• Name an organism that has a cell wall

• What is the advantage of having a cell wall?

• If penicillin prevents bacteria forming peptide cross-linkages in cell walls, how does penicillin work?

Starter- B2 lesson 3Immunity

Discuss with the person next to you.

(at your discretion)

• What is the worst illness you’ve ever had?• Have you ever been into hospital (apart from

birth)• Have you taken medicine for an illness (what

was it)• How did it work?

• Antibiotics

• Read together pg 40 and 41 – summarise in your own words

• Question 1 - 5

Ways to fight diseases

Vaccine

• Draw diagrams from page 44 showing how a vaccine works

SMALL POX – WHY VACCINATED AND

ERADICATED

Smallpox is a serious, contagious, and sometimes fatal infectious disease (30% of infected people died). There is no specific treatment for smallpox disease, and the only prevention is vaccination. The name smallpox is derived from the Latin word for “spotted” and refers to the raised bumps that appear on the face and body of an infected person.

Smallpox

Click

RISKWhat is the…

BENEFIT

What is the…

• WS AB2_11 Is it worth it

Flu AIDS

Why can you Why can you not

catch this again? fight this off?

Susan and June are both young mothers with babies. They are in the park watching their older children play.June: We’re taking little April for her MMR jab tomorrow. I hope she’ll be alright.Susan: You’re mad! Why are you even risking it?June: We’d rather risk her having a bad reaction to the jab than getting one of those diseases.Susan: But those old diseases have almost disappeared now. There’s hardly any chance of her getting one of them.June: But the diseases have only disappeared because people get their children vaccinated.Susan: Yes, but they have disappeared. So now there’s no need to worry.June: But if people don’t get their babies vaccinated the disease will come back.Susan: Yes, but that’s people, not you. There’ll always be plenty of goody-goodies who do what the doctors say. So why should you risk April’s health when you’ve no need to?June: Well, we’re not risking it very much. The doctor told us that the chances of her being badly affected, or affected at all, are very low indeed.Susan: Yes, but why take any risk at all? As long as other people are having their babies done, why take the chance? I’m certainly not going to risk my Danny.Susan thinks that it’s stupid to vaccinate your baby. There is a small risk of the baby being badly affected by the vaccine. She thinks that this is OK because enough other people are getting their babies vaccinated. So it’s unlikely that her baby will get the disease.

WS AB2_9 What if everyone did that

Whooping cough

• Rd pages 47 and 48

Cut and stick viewpoints

Whiteboard quiz

Whatcha know now eh??

10 mins to finish a postcard for a doctors surgery for mums awaiting

an MMR jab

Pros

cons

consequences

advice

How it works

Which is riskier?

Nuclear Power or Peanut Butter?

How would you know?• When people talk about risk what do

they say?

Rank these in order of highest to lowest risk

• travelling in a plane • cycling • driving a car • living near a nuclear power

plant

• living in Cornwall • living in a city • smoking

Rank these in order of highest to lowest risk

• travelling in a plane • cycling • driving a car • living near a nuclear power

plant • fall-out from a nuclear

accident such as Chernobyl • living in Cornwall • living in a city • smoking

We’ll find out later if you were right!

An example about perception of risk…

People are still very frightened about BSE as they did not volunteer to take a risk of catching disease when they bought the food. However, some people will volunteer to aid refugees in war.

Who perceives that the risk is larger?

Whether or not you volunteer for the risk affects your perception

3 other things that affect your perception…

• Can you think of a risk that does not affect people or an area equally?

• Can you think of a risk that results from a man-made rather than a natural source?

• Can you think of a risk where there is a threat of death in some form?

Some hints… • Can you think of a

risk that does not affect people or an area equally?

• Can you think of a risk that results from a man-made rather than a natural source?

• Can you think of a risk where there is a threat of death in some form?

Bird flu Mobile phone masts

Climate change

All these risks give an equal probability of increasing your chance of death by

one part in a million: Activity Cause of death Smoking just 14 cigarettes Cancer or heart disease Travel 10 miles by bicycle Accident Travel 1000 miles by jet plane Accident Have 1 chest x-ray Cancer Drinking 30 cans of a diet drink Cancer (f rom saccharin) Living f or 2 days in a polluted city such as New York

Air pollution

Living 150 years within 20 miles of a nuclear power plant

Cancer

Is this better? Activity Expected reduction in lif espan Smoking 10 cigarettes a day 6 years Being 15% overweight 2 years Moderate alcohol consumption 1 year Working in agriculture 320 days Working in construction 227 days Working in a nuclear plant (10 mSv per year) 51 days Activity Expected reduction in lif espan

Is this better? Activity Expected reduction in lif espan Smoking 10 cigarettes a day 6 years Being 15% overweight 2 years Moderate alcohol consumption 1 year Working in agriculture 320 days Working in construction 227 days Working in a nuclear plant (10 mSv per year) 51 days Activity Expected reduction in lif espan

Were you right?

So what is risk?

risk = probability x consequence


Apply this equation to bungee jumping


Apply this equation to driving a car


Apply this equation to having a swimming pool in your back garden and having

small children


Apply this equation to getting out of bed in

the morning

X-rays… Are they safe?

Another way of expressing risk…

• In the 1980s the following research was published:– Women who take the contraceptive pill have a

50% increased risk of cervical cancer.

Another way of expressing risk…

• In the 1980s the following research was published:– Out of 100,000 women not on the pill 4 are

likely to get cervical cancer.– Out of 100,000 women on the pill 6 are likely

to get cervical cancer.– This is a increase of 50%.

…. What do you think now?

Arteries and veins

Brainpop

Coronary Arteries

• How the heart itself lives??

• Bring oxygen and glucose to the heart muscles

• Fatty lumps can block it and bring on a heart attack

Video IB.2

As the atrium fills with blood, the valves are closed.

When the atrium contracts and squeeze the blood, the valves are pushed open.

These valves are connected to the side wall of the heart by tough tendons.

These tendons allow the valves to close but not invert.

valve

tendon

wall of ventricle

These tendons can be compared to an arm holding onto the handle of a door.

The arm bends as the door is opened.

When the door is closed the arm is fully extended.

It would be impossible for the door to open in the other direction without the person moving with it.

The tendon (represented by the arm) is held in a fixed position and therefore the valve (door) can only open in one direction.

The blood will naturally push against the valve.

However, the valves remain firmly shut.

In this way, the blood can be moved from chamber to chamber quite efficiently.

The valves prevent the blood from moving in the wrong direction.

we also find valves here ...and here!

These extra valves stop the blood from re-entering the heart when it is pumped from the ventricles.

When the blood knocks against the second set of heart valves, it makes a ‘dub’ like sound.

valve

ventricle

artery The blood ‘slaps’ against the valve and then passes along the artery.

These two sounds – lub and dub – are actually what we hear as our heartbeat. So our heartbeat is in fact the sound of the valves opening and closing.

When the blood knocks against the first heart valves, it makes a ‘lub’ like sound.

Heart disease

• AB2.9 Video Cholesterol and the heart

1 min talk about healthy hearts

Plenery

HEART DISEASE (T or F)1.Heart attacks are common in the UK 2.Only men have heart attacks.3.Young people don’t have heart attacks.4.Smoking increases your risk of heart attack.5.Heart attacks happen when arteries to the heart are

blocked.6.Heart attacks are always fatal.7.When you have a heart attack, some of your muscle dies.8.Heart muscle dies when it doesn’t get oxygen.9.Any fat in your diet is harmful.10.Being overweight puts a strain on your heart.

!!! BREAD IS DANGEROUS !!! Research on bread indicates that:

1. More than 98 percent of convicted felons are bread users.

2. Fully HALF of all children who grow up in bread-consuming households score below average on standardized tests.

3. In the 18th century, when virtually all bread was baked in the home, the average life expectancy was less than 50 years; infant mortality rates were unacceptably high; many women died in childbirth; and diseases such as typhoid, yellow fever, and influenza ravaged whole nations.

4. More than 90 percent of violent crimes are committed within 24 hours of eating bread.

5. Bread is made from a substance called "dough." It has been proven that as little as one pound of dough can be used to suffocate a mouse. The average American eats more bread than that in one month!

6. Primitive tribal societies that have no bread exhibit a low incidence of cancer, Alzheimer's, Parkinson's disease, and osteoporosis.

7. Bread has been proven to be addictive. Subjects deprived of bread and given only water to eat begged for bread after as little as two days.

Videos

Epidemiological studies1. Describe the correlation between smoking

and lung cancer.

2. Is one case of a smoker dying of lung cancer enough to prove a link?

3. How big was the study by Doll and Hill which gave more evidence that smoking caused lung cancer?

4. What was the final piece of the puzzle that confirmed smoking causes lung cancer?

• Read page and do Q 1-6

Starter - What are the 7 life Starter - What are the 7 life processes ? (things that all processes ? (things that all

living things do)living things do) Use MRS GREN to help you… Use MRS GREN to help you…

1.1. M =M =2.2. R =R =3.3. S =S =

4.4. G =G =5.5. R =R =6.6. E =E =7.7. N =N =

Life Process Life Process What it MeansWhat it Means

MM MMovementovement M _ _ _ all or parts of M _ _ _ all or parts of themselves.themselves.

RR R _ R _ p rp r _ _ dd _ _ _ _ tt _ _ _ n_ n Make m_re living Make m_re living th_ _ gs like th_ _ gs like themselvesthemselves

SS S _ S _ n _ it _ v _ _ _n _ it _ v _ _ _ Se _ se and re _ c _ Se _ se and re _ c _ to things around to things around

themthem

Life Process

What it Means

G G_ _ wt _ Increase in cell n_ m _ _ r and/or

s_ z _ .R Respiration Use a chemical reaction

to release e_ _ _ g _ from f _ _ d.

E Excretion Get rid of w_ _ t _ materials they make

N N _ tr _t _ _ n Need various substances to help them r _ p_ _ r

and g _ _ _.

• http://www.youtube.com/watch?v=UaYHRx9-v2M

Introduction

• The oldest preserved

medical document is

from Egypt.

• It was written in 1570

and is 20 metres long.

• Over 700 remedies are

included.

• Many diseases are

described, including

diabetes and arthritis.

• There have always

been medical experts.

• In 1804 bloodletting

was used to treat many

illnesses.

• This 18th century kit was used for drilling a hole into

the patient’s skull.

• This treatment was used for centuries before this.

• But anaesthetics weren’t introduced until 1846.

• This picture shows the first public operation with

anaesthetic.

• New technology has

helped doctors make a

better diagnosis.

• For example, X-rays

show bones.

MRI scans give

information about soft

parts of the body.

So do ultrasounds.

• Now doctors can get a

lot of information

without having to go

into the patient’s body.

• Treatments have also

changed as scientists

have learnt more about

how the body works.

• There are many medical challenges still to

overcome.

• Perhaps one of the most difficult is how to give

expensive treatment to everyone who needs it.

Some very large microbes

• You may have seen pictures of bugs living in your house before. These bugs although scary looking are much, much larger than what we will talk about

Imaginary Animals?

Bee mites. Coloured scanning electron micrograph (SEM) of bee mites on the body of a bee. These

parasites feed by cutting into the surface membranes of the bee. In large numbers they can

devastate colonies of bees.

Dust mites. Coloured scanning electron

micrograph (SEM) of two dust mites on fabric

fibres. Millions of dust mites inhabit the home,

feeding on shed skin cells. They mainly live in

furniture, and are invisible to the naked eye due to

their size. The excrement and dead bodies of these mites may cause allergic reactions in susceptible

people.

Magnification: x150

Follicle mites. Coloured scanning electron

micrograph (SEM) of follicle or eyelash mites

These harmless parasites infest hair follicles (holes in the skin which contain the roots of hairs) around the eyelids, nose and in

the ear canals of humans. One follicle may contain up to 25 growing mites. They feed on oily

secretions from the glands, as well as dead

skin cells.

Magnification: x180 at 6x7cm size.

Lice. Two lice, Phthirus pubis, also known as crab lice, hanging from human hair. An adult louse and infant louse are seen. An infestation of P. pubis causes pediculosis, the symptoms of which are severe itching and a rash. The lice suck blood, feeding five times a day. Each of the louse's six legs terminates in a massive claw, which folds inward to meet a thumb-like projection on the opposite side. The louse climbs & swings through its habitat, locking into position when disturbed. Magnification: x20 at 6x7cm size.

Head louse and egg. Coloured scanning electron

micrograph (SEM) of a human head louse (Pediculus

humanus capitis) and an egg attached to a strand of

human hair. The louse ranges in size from 2 to 3 millimetres in length. Each of its six legs end in a claw. Adult lice live for approximately 30 days,

and during this time a female may lay 100 eggs (nits), which are glued to the

bottom of hair shafts. An infestation of lice causes itching due to an allergic reaction to louse saliva.

Bed bug. Coloured scanning electron micrograph (SEM) of 2 parasitic bed bugs, on fabric. The head has a pair of eyes (red), two

antennae, and piercing mouthparts. A regular diet of blood is necessary for bed bugs to reach maturity. A parasite of humans,

this species feeds at night and after a blood meal the body becomes quite swollen. The bite of a bed bug produces swellings on the skin. It is painful and may be lasting in some cases. During the day the

bed bug lives in mattresses, floors, or in tears in furniture. Magnification: x10 at 6x7cm size.

Dog tick, seen from the front. This bloodsucking parasite of dogs can transmit to humans a bacteria which causes spotted fever or tick fever, a form of typhus. The tick's specialised mouthparts are adapted to pierce the skin of the host. It has a flattened body which swells after a meal. Magnification: x22 at 5x7cm size.

Feeding tick. Coloured scanning electron micrograph of a tick feeding head-down in

human skin.

Ticks are arachnids which parasitise mammals, birds and

reptiles, feeding on their blood.

In the feeding process, they cut through the skin with the

scissor-like action of their modified mouthparts, and

thrust their hypostome (feeding tool) through the

lacerated skin, and lock into the surrounding tissues.

Ticks can transmit diseases such as relapsing fever and

Lyme disease, and their bites may become infected.


Deer tick. Coloured scanning electron micrograph of a deer tick. This is a bloodsucking parasite of animals and humans. Its sensory pedipalps (lower left) are seen shielding its specialised mouthparts, which are used to pierce

the host's skin. Hairs on the pedipalps locate the host by detecting air-borne vibrations.


• Even smaller…..

• So what is Bacteria???

Bacteria is a single cell organism about 100 times smaller than a human cell.

Bacteria can reproduce outside of a human and are used to create cheese.

They can also cause the food poisoning and tooth decay.

Bacteria

Chicken skin infected with bacteria

Bacteria found in water Bacteria on human skin

• So what is a Virus???

A virus is another microbe. It is about 100 000 smaller than a human cell.

A virus needs another cell (a host cell) in order to reproduce.

Viruses are responsible for causing HIV, common cold and chickenpox.

8C Even smaller!

Fungus Fungi are another form of microbe. There are many different varieties ranging from bread mould to mushrooms.

Yeast is a type of fungus that we use everyday to make bread

penicillin

fungus - yeast

b2 – lesson 1 keeping healthy

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