Recommended for Core science students studying B1. NB: Only for the AQA exam board. For notes, look below: B1.1 - Keeping Healthy: http://www.docbrown.info/page20/AQAscibio11.htm B1.2 - Nerves and Hormones: http://www.docbrown.info/page20/AQAscibio12.htm B1.3 - The use and abuse of drugs: http://www.docbrown.info/page20/AQAscibio13.htm B1.4 - Interdependence and adaptation: http://www.docbrown.info/page20/AQAscibio14.htm B1.5 - Energy and biomass in Food Chains: http://www.docbrown.info/page20/AQAscibio13.htm B1.6 - Waste materials from plants and animals: http://www.docbrown.info/page20/AQAscibio16.htm B1.7 - Genetic variation and its controls: http://www.docbrown.info/page20/AQAscibio17.htm B1.8 - Evolution: http://www.docbrown.info/page20/AQAscibio18.htm

1. slit-like nostrils and two
rows of eyelashes
thin fur to allow easy heat
loss
a large surface area to
volume ratio to maximise
heat loss
Hump which stores fat
large, flat feet to spread
weight
white appearance for
camouflage
thick layers of fat and fur for
insulation
a small surface area to
volume ratio, to minimise heat
loss
a greasy waterproof coat
large furry feet to distribute
weight
Keywords:Adaptation,Competition,Inherit,AsexualReproduction,Dominant,Recessive,Allele A cell nucleus
contains 46
Chromosomes, which
carry genes and are
made of DNA.
Different versions of
genes are called
alleles.
Extinction, Evolution, Darwin, Natural Selection, Mutation, Vertebrate, Pollution, Acid Rain, FSH, LH, Hormone, Oestrogen, Mutualist
Competition
Animals
-food
-water
-territory
-mates
Plants
-light
-water
-space
-nutrients
Sexual Asexual
2 Parents;
fusion of
gametes
1 Parent
Lots of
Variation
No
Variation;
clones
Cacti adaptations:
Stems that can store water.
Widespread root systems =
collect water from a large area;
support/anchor the plant.
Spines not leaves = reduced
water loss & protection. Fewer
stomata = less water lossTemperature
Monitored by
thermoregulator
y centre in brain
and receptors in
skin.
Too Hot
-hair lies flat
-blood vessels
dilate so heat
lost through skin
-sweat produced
Too Cold
-goosebumps &
hairs trap air
-blood vessels
constrict
-no sweat
-shiver,
respiration
releases heat
Scientific names
(binomials) provide
info. on evolutionary
relatedness
Genus Species
Pan paniscus
Survival
of the
fittest!
Reproduction
Stimuli/Receptor Sense Organ
Touch/pressure Skin
Sound Ears
Light Eyes
A Motor Neuron
Reflex
Arc
Plant Hormones: Auxin
controls growth. Diffuses
away from light. Promotes
growth in shoots. Inhibits
growth in roots. Shoots =
+ively phototropic (grow
towards light); -ively
gravitropic (grow against
gravity). Roots =
opposite.
Hormones
Gland > Secretion > Target organ

2. Theories of Evolution
Evolution = random progressive change over long
period of time
Lamarck- inheritance of acquired characteristics
Darwin- natural selection & survival of the fittest
Fossils show how
organisms have
changed, but don’t
often form and are
usually fragmented
Extinction due to….
•Changes in environment
•New predators
•New competitors
•Disease
Owls
Blackbirds
Caterpillars
Oak tree
Pyramids of Biomass
Show amount of material
at each stage
Always a pyramid shape
because energy & carbon
is lost….
- Respiration: releases
CO2, energy used in
movement + heat
production
(mammals/birds)
- Not all organisms eaten
- Waste: faeces + urine
The Carbon Cycle
-Stored as CO2, or
fats/proteins/carbs
-Decay carried out
by decomposers
Food
Chains
Pyramids of numbers show the number of organisms at each level; not always a pyramid shape
What is the source of all
energy?
1. Mutation causes…
2. Variation, with
3. Some individuals
better adapted
4. Better adapted
survive and
reproduce
5. Offspring inherit
adaptation and
also benefit
E.g. Believed that the offspring of mice
who had their tails chopped off would
also have no tails…WRONG
Electric
shock to
stimulate
cell division
Adult Cell CloningAdult cell cloning: new
individual is an exact replica
of just one parent
Embryo transplant: two
parents’ gametes, artificial
insemination, embryo
formed, split into several and
each placed in a surrogate
uterus
What are the concerns with
these procedures?
Genetic Engineering
Immune Response (1 of 3)
White blood cells >
produce antibodies >
recognise foreign
pathogens > faster
response next time

3. Why does a person become
malnoushired?
Give two signs of
malnourishment.
Complete the table to
evaluate the use of statins
and cholesterol blockers for
treating high cholesterol
levels.
What two nutrients do we
need in small amounts to
maintain good health.
Use the information on the left
to work out the BMI for the
following people. What dietary and
medical advice would you give to
each?
State three things that affect
metabolic rate:
Define metabolic
rate
Name the three major nutrient
groups and state why we need each
Name two factors that
influence blood
cholesterol levels.
Name Mass (kg) Height (m) BMI Advice
Mr X
Miss P
Mrs Q
70
65
54
1.90
1.43
1.74
19.4
31.8
17.8
What are statins and cholesterol blockers used
for? Explain how each works.
.
Drug Advantages Disadvantages
Statins
Cholesterol
blockers
• .
Name three important things in
the body cholesterol is used for.
BMI = mass in kg
(height in m)2
Underweight <18
Normal 19-24
Overweight 25 - 29
Obese >30
Explain the link between cholesterol and heart disease.
Name a source of:
Saturated fat:
Unsaturated fat:
How can you change the fat intake in your diet
to reduce cholesterol?

4. Why does a person become
malnoushired?
Their diet is not balanced
Give two signs of
malnourishment.
Overweight / underweight
Deficiency disesase
Complete the table to
evaluate the use of statins
and cholesterol blockers for
treating high cholesterol
levels.
What two nutrients do we need
in small amounts to maintain
good health.
Vitamins
Minerals
Use the information on the left
to work out the BMI for the
following people. What dietary and
medical advice would you give to
each?
State three things that affect
metabolic rate:
•Activity Levels
•The ratio of fat to muscle in the body
•Genes (inherited factors)
Define metabolic
rate
is the rate at which all
the chemical reactions
in the cells of the body
are carried out.
Name the three major nutrient
groups and state why we need each
•Carbohydrate – energy source
•Fat – energy, make hormones,
insulation
•Protein – build new cells
Name two factors that
influence blood
cholesterol levels. Diet
Genes
Name Mass (kg) Height (m) BMI Advice
Mr X
Miss P
Mrs Q
70
65
54
1.90
1.43
1.74
19.4
31.8
17.8
Healthy
Obese –eat less fat and
sugar; exercise more
Underweight – increase
calorie intake
What are statins and chloesterol blockers used
for? Explain how each works.
Drugs that lower blood cholesterol.
Statins block enzyme in liver.
Cholesterol blockers reduce dietary absorption.
Drug Advantages Disadvantages
Statins
Cholesterol
blockers
• Can lower cholesterol to
zero
• Good for people with high
cholesterol due to genetics
• Good for people with high
cholesterol due to diet
• Less side effects than
• Need cholesterol to make
hormones etc
• Potentially fatal side effects
• Can interact badly with
other drugs.
• Can cause diarrhoea.
Name three important things in the
body cholesterol is used for.
Cell membranes
Steroid hormones
Bile
BMI = mass in kg
(height in m)2
Underweight <18
Normal 19-24
Overweight 25 - 29
Obese >30
Explain the link between cholesterol and heart disease.
If you have a high ratio of LDLs to HDLs you have an increased
risk of heart disease.
This encourages cholesterol to be deposited in the walls of
coronary arteries,
Blockage prevents glucose and oxygen reaching the heart muscle
so heart muscle cells cannot respire so die.
Name a source of:
Saturated fat: Meat, dairy, eggs
Unsaturated fat: olive oil,
peanuts, corn oil, sunflower oil,
oily fish, margarine
How can you change the fat intake in your diet
to reduce cholesterol?
Eat less saturated fats and more unsaturated

5. What 3 diseases
does MMR vaccine
protect from?
Explain how the following make you ill:
Bacteria
Viruses
How can the following drugs be used
to treat disease?
Painkillers
Antibiotics
Explain how vaccination works:
Explain how white blood cells protect
you from disease.
What is a pathogen?
.
Outline the experiments carried out by Ignaz
Semmelweiss and explain the contribution of these to
modern medicine.
Why can’t antibiotics be used
to kill viruses?
Why is overuse of antibiotics a problem?
How can we reduce this problem?
Why are antibiotics used in
farming?
Explain how antibiotic resistance
develops in bacteria.
What is a mutation?
Why is mutatioin in pathogens
problematic?
What is a sterile culture.
.
Give 2 reasons it is important to keep
cultures sterile. .
List 4 precautions you must take when carrying out
aseptic technique to grow a sterile culture
1.
What temperature should
we incubate cultures at in
school and why? How does
this compare to industry?
.

6. What 3 diseases
does MMR vaccine
protect from?
Measles
Mumps
Rubella
Explain how the following make you ill:
Bacteria Reproduce rapidly and
produce toxins
Viruses reproduce inside e cells and
damage them
How can the following drugs be used
to treat disease?
Painkillers relieve symptoms (don’t
kill pathogen)
Antibiotics Kill bacteria
Explain how vaccination works:
•Small amount of dead or inactive pathogen injected
•Stimulates memory cells to form
•Next time pathogen enters body white blood cells
make antibodies faster and in greater numbers
Explain how white blood cells protect
you from disease.
•Ingest pathogens (phagocytosis)
•Produce antibodies – destroy specific
bacteria or viruses
•Produce antitoxins – neutralise
toxins released by pathogens
What is a pathogen?
Microoganism that causes disease.
Outline the experiments carried out by Ignaz
Semmelweiss and explain the contribution of these to
modern medicine.
Noted death rates on maternity wards much lower when
midwives delivered compared to doctors - realised doctors
were transferring disease from surgery
Encouraged use of chloride of lime to wash hands and kill
bacteria - Death rates drastically fell
Shows importance of handwashing to prevent spread of
infection
Why can’t antibiotics be used
to kill viruses?
Viruses replicate inside human
cells so the antibiotic can’t
reach them or would kill the
human cell.
Why is overuse of antibiotics a problem?
Selects for antibiotic resistant bacteria to survive. These
are hard to treat.
How can we reduce this problem?
Do not use antibiotics for minor infections
Reduce use in agriculture
Why are antibiotics used in
farming?
Help animals gain weight – less
energy spent overcoming
infection
Increase profits – prevent
spread of infection
Explain how antibiotic resistance
develops in bacteria.
Bacteria mutate by chance
Bacteria with mutation not killed by
antibiotic
These cells can survive to reproduce
And pass the gene for resistance to
their offspring – population of
resistant bacteria increases
What is a mutation?
Change in a gene
Why is mutatioin in pathogens
problematic?
Creates new strains that
people have no immunity to or
are resistant to antibiotics
What is a sterile culture.
Culture of only one type of microorganism.
Give 2 reasons it is important to keep
cultures sterile. .
Other microbes would use up food
resources
Other microbes may produce dangerous
toxins
List 4 precautions you must take when carrying out
aseptic technique to grow a sterile cuture
1. Sterilise petri dish and culture medium before use
2. Sterilise innoculating loop by passing through a flame
3. Tape lid to prevent contamination from air
4. Work near a flame
What temperature should
we incubate cultures at in
school and why? How does
this compare to industry?
25oC – to prevent growth of
human pathogens.
Industry higher – faster
growth rate.

7. What is involved in phase two drugs
testing?
Complete the table to evaluate the use
of cannabis
What does phase one drug testing
involve and why is it necessary?
Why did the use of Thalidomide cause controversy?
What is meant by
A blind trial?
Double blind trial?
What would the placebo be if the real
drug was:
A tablet?
An injection?
Advantages Disadvantages
What is a drug?
What was Thalidomide
originally developed as?
What is it now used to treat?
Give a negative effecs on
the body of
Smoking
Drinking alcohol
What is drug addiction? Name a very addictive
drug.?
What is the advantage of blind
trials?
Why is the overall impact of
legal drugs on society greater
than illegal drugs?
What are withdrawal symptoms? Give an
example.
Why might an athlete take the following?
•Anabolic steroid
•Stimulants
•Analgesics
•Stimulants

8. What is involved in phase two drugs
testing?
Drug tested on healty volunteers
Start with low dose – gradually
increased until effective dose found
Complete the table to evaluate the use
of cannabis
What does phase one drug testing
involve and why is it necessary?
Test drug on cells, tissues or animals
Safety testing - check for toxicity and
interaction with other drugs.
Why did the use of Thalidomide cause controversy?
Found to relieve morning sickness but had not been
tested on pregnant animals – babies born with severe limb
abnormalities.
What is meant by
A blind trial? Patients do not now who
gets drug and who gets placebo
Double blind trial? Neither doctor nor
patient knows who gets drug or placebo
What would the placebo be if the real
drug was:
A tablet? Sugar pill
An injection? Saline injection
Advantages Disadvantages
Can be medicinal:
glaucoma / MS /
Cancer
Relaxant
Strong evidence
suggesting causes mental
illness
Expensive
May lead to use of more
dangerous drugs
What is a drug?
Chemical that alters the way the body works.
What was Thalidomide originally
developed as?
Sleeping Pill
What is it now used to treat?
Leprosy
Some types of cancer
Give a negative effecs on
the body of
Smoking Lung cancer / Low
birth weight / Heart
disease / Emphysema etc
Drinking alcohol Liver
cancer / cirrhosis etc
What is drug addiction? Name a very addictive
drug.?
When your body becomes dependent on a drug due
to frequent use– durg alters body chemistry so
badly that you cannot function normally without it.
Eg, heroin, cocaine
What is the advantage of blind
trials?
Avoid bias
Why is the overall impact of legal
drugs on society greater than
illegal drugs?
More people use legal drugs
What are withdrawal symptoms? Give an example.
Unpleaseant side effects experienced when you
stop taking an addictive drug.
Eg. Tremors, palpitations, sweating, headaches
etc
Why might an althlete take the following?
•Anabolic steroid increase muscle mass
•Stimulants Liver cancer / cirrhosis etc
•Analgesics relive pain
•Stimulants make reactions faster