Download Other Risk Factors File

Other Risk Factors
Topic 1.3
Specification
 12. Describe the factors that increase the risk of CVD
(genetic, diet, age, gender, high blood pressure, smoking
and inactivity).
 15. Discuss how people use scientific knowledge about the
effects of diet (including obesity indicators), exercise and
smoking to reduce their risk of coronary heart disease.
 16. Describe how to investigate the vitamin C content of
food and drink.
 9. Describe how the effect of caffeine on heart rate in
Daphnia can be investigated practically, and discuss
whether there are ethical issues in the use of invertebrates.
Risk Factors for CVD
 State some of the risk factors for CVD:












Old age
Gender – males more likely
High blood pressure
Obesity
Blood cholesterol levels – High LDLs and low HDLs
Smoking
Inactivity
Heredity – mutations and different alleles
Lack of antioxidants in diet
High salt diet
Too much stress
High alcohol intake
Homework- Complete Risk Factors Table for the factors written in
Risk Factors for CVD
 State some of the risk factors for CVD:












Old age
Gender – males more likely
High blood pressure
Obesity
Blood cholesterol levels – High LDLs and low HDLs
Smoking
Inactivity
Heredity – mutations and different alleles
Lack of antioxidants in diet
High salt diet
Too much stress
High alcohol intake
Using book and following slides complete Risk Factors Table for
Smoking
 Brainstorm harmful effects of smoking.
 Carbon monoxide forms a complex with haemoglobin in
red blood cells to form carboxyhaemoglobin
 Reduced O2 supply causes an increased heart rate which
increases your cardiac output and thus a higher blood
pressure
 Nicotine causes adrenaline release:
 Higher heart rate and arteries constrict.
 Higher blood pressure
 Other chemicals found in smoke can damage blood
vessel walls: atherosclerosis.
 It has also been shown that there is a negative correlation
between smoking and HDL cholesterol levels
Inactivity
 Major risk factor for CVD
 What is a recommended amount of exercise per week?
 30 minutes, 5 times a week
 Why does exercise reduce risk?





Lowers blood pressure
Helps weight maintenance
Raises HDL cholesterol
Decreases risk of type II diabetes
Increases chances of surviving a stroke or heart attack.
Risk Factors for CVD
 State some of the risk factors for CVD:












Old age
Gender – males more likely
High blood pressure
Obesity
Blood cholesterol levels – High LDLs and low HDLs
Smoking
Inactivity
Heredity – mutations and different alleles
Lack of antioxidants in diet
High salt diet
Too much stress
High alcohol intake
Complete Risk Factors Table for the factor written in red
Complete Activity 1.19
Heredity
 Read page 45, Heredity and risk
 Brainstorm some terms used for inheritance:
 Gene
 Allele
 Genotype
 Phenotype
 Recessive
 Dominant
 Heterozygous
 Homozygous
 Gamete
 Haploid
 Diploid
 Mutation
 Match the terms to their definitions
Heredity Definitions- matching excercise
 Gene

The alleles present for a gene
 Allele

A change in the sequence of DNA of a gene
 Recessive

A section of DNA that codes for a protein /characteristic. Eg. Eye colour
 Dominant

This type of allele will only determine a characteristic (be expressed) if
there are no dominant ones present
 Genotype

This term describes two identical alleles being present for a gene
 Phenotype

A sex cell, eg. sperm or egg cell
 Heterozygous 
 Homozygous
 Gamete
 Haploid
 Diploid
 Mutation
This type of allele will always determine a characteristic (be expressed)

The normal number of chromosomes present in the cell

This term describes two different alleles being present for a gene

The characteristc expressed by the alleles present for a gene

Half the normal number of chromosomes present in the cell

A different form of the same gene. Eg. For eye colour gene, brown,
green, blue
Heredity
Complete using
pages 45-46
Coronary heart disease
genetic disorders
Consequence on
blood cholesterol
Effect of
mutation
Name
Single gene
mutations
Several gene
mutations
Heredity
Complete using
pages 45-46
Coronary heart disease
genetic disorders
Name
Mutations in the LDLR gene
cause LDL receptors
(involved in removal of LDL
from blood) to not form or to
have a less efficient shape.
Consequence on
blood cholesterol
Familial
hypercholestrolaemia (FH)
Effect of
mutation
Single gene
mutations
Therefore higher levels
of LDL, more cholesterol
(LDL) stays in blood
Several gene
mutations
Apolipoprotein
gene cluster
Mutations in
these genes
affect the protein
found in HDLs
Therefore less functioning
HDL and less cholesterol
removed by liver (more
stays in blood)
Mutations in
these genes
affect the protein
found in LDLs
Therefore higher levels
of LDL so more
cholesterol (LDL) stays
in blood
Genetically inherited conditions
 Example: Sickle cell anemia, a recessive disease
whereby affected offspring have abnormally shaped
haemoglobin and are less efficient at carrying oxygen
Parent genotype
Aa
Aa
Parent phenotype
Gametes
Gametes
 There is a _________ chance of a child suffering from
sickle cell anemia
Heredity
 Compare the inheritance of a single gene disorder like sickle cell
anaemia with inheritance of CVD.
 Diseases like CVD are multifactorial: genes may play a role
(mutations in certain genes increase your risk of CVD), but in
combination with other factors like:
_________________________________________________
Risk Factors for CVD
 State some of the risk factors for CVD:












Old age
Gender – males more likely
High blood pressure
Obesity
Blood cholesterol levels – High LDLs and low HDLs
Smoking
Inactivity
Heredity – mutations and different alleles
Lack of antioxidants in diet
High salt diet
Too much stress
High alcohol intake
Complete Risk Factors Table for the factor written in green
Complete Activity 1.19
Antioxidants
 Read page 47
 What are free radicals?
 When an atom in the molecule has an unpaired electron
(desperate to find a partner)
 This desperation leads the atom to «steal» electrons from
other molecules, damaging them.
 DNA (genes),enzymes, lipoproteins and platelets can be
destroyed like this.
 What is the correlation between antioxidants and risk of
CVD? Is there a causal connection? If so explain it.
 Lack of antioxidants increases risk
 Antioxidants provide an electron (in the form of a H atom
which has one unpaired electron) to the unpaired electron
High salt diet
 What causes someone to have a high salt diet?
 Eating too many procesed foods
 What health problems can it cause?
 The kidneys retain water and therefore more water is in
the blood, resulting in higher blood pressure and
increased risks of athrosclerosis
Too much stress
 Why might too much stress lead to a higher risk of
coronoary heart disease?
 When adrenaline released – arteries and arterioles to
constrict, increased heart rate – higher blood pressure
 Overeating, poor diet (high in salt, saturated fats)
 Higher alcohol consumption – raises blood pressure
High alcohol consumption
 Heavy drinkers are at a far greater risk of heart
disease, why?
 Higher blood pressure
 Contributes to obesity
 Can cause irregular heartbeat
 Tissue damage to liver, brain and heart
 Liver damage: Less cholesterol removed from blood
 Some of the alcohol broken down in the liver is
turned into VLDLs increasing risk of atherosclerosis
 Moderate drinking can increase HDLs and wine
contains antioxidants
 Complete Activity 1.24