Transcript Play your cards right!

Infection
Treatment
Cholera bacterium is ingested and enters
the small intestine.
Oral rehydration solution (ORS) is given
to the infected patient.
Cholera bacterium secretes enterotoxin
subunit B.
ORS contains glucose and sodium, and
also bicarbonate and potassium ions.
Enterotoxin subunit B attaches to a
receptor on the cell membrane of the
small intestine microvilli.
The presence of glucose and sodium in
the small intestine causes the carrier
protein to co-transport these into the
small intestine cell.
This causes the release of enterotoxin
subunit A inside the small intestine cell
This changes the water potential and
water flows back into the small intestine
cell by osmosis.
This causes ion channels to open and
sodium ions flow back from the
bloodstream into the small intestine
lumen.
Water also flows back into the small
intestine lumen by osmosis, causing
rice water (diarrhoea).
Water, glucose, sodium and the other
ions now diffuse into the bloodstream.
The patient is cured!  However, the
bacterium has been known to survive
upto 50 days in faeces, so Colin the
cholera and co. may now have infected
someone else… 
Homework
• Answer the past exam questions on coronary
heart disease and cancer.
(We will be learning about these two topics today)
Due in: Friday 3rd October (Day 3, Period 5)
• BHF animation
Play your cards right!
http://www.youtube.com/watch?v=ThMIAHxdawI&feature=related
For each picture that appears,
say whether it would HIGHER or
LOWER your risk of developing
CHD or cancer
You have been warned!
Cancer and CHD
• Aims:
• To know how lifestyle can affect your risk of
developing some diseases
- In particular, cancer and coronary heart
disease (CHD)
• To understand how specific risk factors can
contribute to (not cause!!) cancer and CHD
How much do you already know…?
• What are the differences between meiosis and
mitosis?
• Which of these two types of cell division do you
think is involved in cancer?
• What is the name given to an agent that causes
cancer?
• Name the two types of tumour caused by cancer.
• How many cancer treatments do you know of?
http://www.cancerquest.org/images/Documentary/En
glish/DocInterfaceEng.swf
Cancer Treatment
• Chemotherapy – stops the cancer cells from
replicating themselves
• Radiotherapy – damages DNA so that the
cell destroys itself
• Surgery – removal of the tumour and
surrounding tissue.
On a lighter note!
• 80% of most cancers are curable if diagnosed
early 
• Science has already made vast improvements
already in treating cancer, and continue to do so
• You are now aware of the risk factors which
make you more susceptible to getting cancer
(and CHD), so YOU have the choice to change
your bad habitats now!
CVD – cardiovascular disease
• Most common form is Coronary Heart
Disease (CHD)
• In economically developed countries, the
main cause of CHD is atherosclerosis.
• http://uk.youtube.com/watch?v=fLonh7ZesKs
• http://uk.youtube.com/watch?v=EQVEdFSlUG
U
• Complete the following activity on
atherosclerosis…
Re-arrange the following steps into a flow-charts, detailing how an
atheroma is formed. Then draw pictures next to certain steps
showing what a cross-section of the artery would look like.
The deposit builds
up further and
hardens causing
arteriosclerosis
Blood flow is
restricted and
blood pressure
increases
White blood cells,
lipids, dead cells
and connective
tissue are deposited
This causes fatty
streaks
Healthy artery
An aneurysm or
thrombosis can
then develop
The inner lining of
the artery
(endothelium) is
damaged
This partially
blocks the lumen
of the artery
This deposition is
called an atheroma
(fibrous plaque)
Atherosclerosis
Aneurysm
Thrombosis
(make your own notes here from my explanation)
A burst blood vessel associated
with an aneurysm, blood clot or
head injury can cause a …
Stroke
Blockage or severe narrowing of one of the
coronary arteries that supply the heart can
lead to angina pectoris, or more severely, a
‘myocardial infarction’
Cholesterol
• Diet high in saturated fats causes excess cholesterol in blood
• Part of the fatty deposits in atheromas
• Accelerates atherosclerosis
High Blood Pressure
• Hypertension
• Excessive salt intake, saturated fats, lack of exercise, stress,
smoking, high alcohol consumption
• Increased risk of damage to the artery wall through
increased pressure
• Heart has to work harder to pump blood around the body –
could cause a myocardial infarction
Smoking and CHD
CO
Nicotine
Carboxyhaemoglobin
(reduced O2 capacity)
Stimulates adrenaline
Heart pumps faster
Hypertension
Angina
during
exercise
Increased heart
rate b.p., reduces
arteries ability to
dilate
Increased risk of CHD &
stroke
RBC
‘sticky’
Increased
risk of
thrombosis
Stroke/myocardial
infarction
True or False
In the UK, one person has a heart attack
every two minutes