genes and health think about gcse – what do you know about genes/genetics? what do these words...

Genes and Health

Think about GCSE – What do you know about Genes/Genetics? What do these words make you think of? What affects do our Genes have on health?

Title: Topic 2: Genes and Health

• Understand what is covered in topic 2 and begin to consider some key points in the topic

• Identify the issues posed people who carry the CF gene• Be able to explain the properties of a gas

exchange system• Understand how cystic fibrosis effects the

lungs of sufferers

Journey through topic.......................................................Journey through topic.......................................................

How changes in DNA can result in genetic disease such as CF including process of DNA replication

Symptoms of CF Focus on structure of lungs and importance of gaseous exchange – in particular surface area to volume ratioStudy cell membrane structure and how substances move across membranes

To explain how faults arise in the cell membrane surface of CF sufferer – learn how genes code for proteins, how proteins are made and how their function is dependent on their structure Role of genes in inheritance

Genetic screening and gene therapy may help people with CFEthical views of new technology

If we have a child – will it have CF? If the child does have CF, how willIt effect its life and our own?

How is CF inherited?

What are the chances of any child inheriting the condition?

Can genetic screening help? What treatments are available?

What does the future hold?

What research may develop in the future?

CF is a common genetic disease

CF is a common genetic disease

CF affects the respiratory, digestive and reproductive systems

CF affects the respiratory, digestive and reproductive systems

Normal Lungs• Layer of mucus coating

tubes of lungs• Produced by goblet cells• Traps dust and micro

organisms• Removed by cilia on

epithelial cells

Lungs of a Cystic Fibrosis Sufferer

• Drier mucus than normal• Sticky and difficult to

remove by cilia cells• Builds up in the airways

Increases Chance of Lung Infections

Reduces Gas Exchange

Gaseous exchange must Be rapid so there is Enough oxygen reachingAll the body’s respiring cells

http://videos.howstuffworks.com/hsw/23424-cell-diffusion-across-the-cell-membrane-video.htm

http://videos.howstuffworks.com/hsw/23424-cell-diffusion-across-the-cell-membrane-video.htm

25B1F9B3.htmhttp://genesandhealth.blogspot.com/http://genesandhealth.blogspot.com/

Large surface area

Numerous number of capillaries around alveoli

Thin walls between alveoli and capillaries

Ficks Law

The three properties of an effective gas exchange system

Rate of diffusion α SA X Difference in ConcThickness of surface

• Large SA• Big difference in concentration• Thin walls

O2

O2 O2

O2O2

O2

O2

O2

O2

O2

CO2

CO2

CO2

CO2

CO2

CO2

CO2

CO2

CO2

CO2

Alveoli

Capillary

Draw what happens next in terms of diffusion - draw as many pictures as you think it takes to explain it

Draw another picture show how diffusion couldBe increased

Draw a final picture showing the factor which reduces gas exchange

Write down Fick’s Law of diffusion

REVIEW

One thing about CF that you would like to know more about

2 effects that CF has on lungs

3 properties of an effective gas exchange system

Find out how to calculate:

VolumeSurface AreaSurface area: volume ratio

You will not be able to do the practical without it!!!!!!!!!!!!!!!!!!!!