Balanced Diet-
Includes
everything
needed for a
healthy body
Different
amounts
of energy
needed,
based on
metabolic
rate
Energy
taken
in>Energy
used=Weight
Lost
Weight
Problems
Eating more energy than needed causes mass
to increase
Obese- Very
overweight
Type 2 diabetes
Coronary Heart diease
Starvation-
Very
underweight
Deficiency disease
Inheritance,
Exercise and
Health
Inherited
factors
affect health
factors, such
as metabolic
rate and
cholesterol
levels
Regular exercise
improves health
as it increases
metabolic rate and
lowers cholesterol
Pathogens and
Disease
Pathogens- Microorganisms
that cause disease
Usually bacteria and viruses
Reproduce rapidly, and may produce toxins
Viruses reproduce inside cells damaging them
Semmelweiss
Discovers how disease is passed from person to person
Introduces hand washing in hospitals
Defence
Mechanisms
Skin stops
pathogens getting in
Pathogens that do enter can be destroyed by white blood cells in the immune system
Can ingest pathogens by digesting and destorying them
Antibodies attach to antigens on
the pathgen to destroy it
Antitoxins neutralise toxins produced
by pathogens
Using Drugs to
Treat Disease
Medicines such as painkiller relieve symptoms, but don't kill pathogens
Antibiotics can't kill viruses
Antibiotics cure bacterial diseases by killing bateria
Viruses are hard to destroy becasue thet reproduce inside cells so there is a risk of
damaging the cells
Growing and
Investigating
Bacteria
Bactera
can be
grown
on agar
jelly
All
materials
used mut
be
sterilised
Prevents
unwanted
microorganisms
contaminating
the culture
Uncontaminated
cultures can be used for
investigations of
antibiotics and
disinfectants
Changing
Pathogens
Pathogens
can change
causing
mutations
These can spread
rapidly due to lack of
immunity to new
strain
New strains can
cause epidemics or
pandemics
Epidemic-
Spread of a
disease
within a
country
Pandemic Spread of a disease internationally
Bacteria can develop
resistance to antibiotics
through natural selection
Immunity
Vaccines
immunise
against
disease
Vaccines
contain
dead or
inactive
pathogens
Encourages
white blood
cells to
produce and
remember
the
antibodies to
destroy the
pathogens
Vaccination
works on
both bacteria
and viruses
How do
we deal
with
disease?
Herd
immunisation,
vaccinating
large
numbers,
protects
society from
the risk of
disease
Coordination
and Control
Responding
to Change
Nervous
system
allows
reaction to
surroundings
Receptors
in sense
organs
detect
external
stimuli
Impulse sent
along sensory
neurone to
brain
Brain
coordinates
response,
which is sent
down motor
neurone
Effector
then
responds
Reflex Actions
Reflex actions
are automatic
responses to a
stimulus and
usually keep us
out of danger
Reflex arc is similar to a normal response, but
instead of going to the brain, the impulse is
processed by a relay neurone in the spinal cord
Between neurones there are
synapses that use chemicals to
pass the impulse over the gap
Hormones and the
Menstrual Cycle
Menstrual
cycle lasts
28 days
with
ovulation
at 14 days
Follicle
Stimulating
Hormone (FSH)-
Made in the
Pituitary Gland
and causes an
egg to mature
and stimulates
the production
of oestrogen
Oestrogen-
Produced
by the
ovaries
and it
inhibits
the
production
of FSH and
stimulate
the
production
of LH and
the womb
lining
Luteinising
Hormone (LH)-
Made in the
Pituitary Gland
and it stimulates
the release of the
matured egg
Artificial
Control of
Fertility
The
contraceptive
pill may
contain
oestrogen and
progesterone
to inhibit FSH
FSH can be given
to help an infertile
woman produce
eggs
Fertility
Treatments
Advantages
Reduces
family size
Woman can
plan
pregnancies
Couples that
couldn't have
children before
can now
Disadvantages
Pill can
cause side
effects
Ethical or
religious
implications
IVF is
expensive
Embryos
may be
destroyed
Controlling
Conditions
Internal conditions of the
body must stay constant
Controlled by the nervous
system and hormones
Water, ion content,
temperature and blood
sugar levels are controlled
Hormones and
the Control of
Plant Growth
Plants
respond to
light,
phototropism,
gravity,
geotropism,
and moisture,
hydrotropism
Auxin is the plant
hormone that controls
geo and phototropism
In a root the auxin gathers on the
underside, and makes the plant where there
is less auxin to grow more, bending the root
towards the ground
In a shoot auxin gathers on
the underside and makes the
part where there is more
auxin to grow, bending the
shoot away from the ground
Using
Hormones
Can have side effects
Misuse of plant
hormones could effect
the environment
Medicine
and
Drugs
Developing
New
Medicines
Drugs are tested
in labs, on animals
and in clinical trial
on healthy and ill
patients
Placebo-
Don't
contain a
drug, are
used to see
if drug does
have effect
Double Blind
Trials- Neither
doctor nor
patient knows
which is the
drug and
which is the
placebo, to
remove bias
Thalidomide,
a sleeping pill,
was found to
cure morning
sickness but
caused birth
defects so
now treats
lepsory
How
Effective
Are
Medicines?
Statins
lower
cholesterol
levels and
have
lowered
heart
disease by
40%
Double
blind trials
should be
used to test
non
prescribed
medicines
to remove
bias
Drugs
Drug- A
chemical
the effect
your
behaviour or
thoughts
Both legal and
illegal drugs
may harm your
body
Chemicals
in cannabis
may cause
mental
illness in
some
Cocaine
and heroin
is very
addictive,
and you
may suffer
from
withdrawal
symptoms
when trying
to stop
taking them
Legal
and
Illegal
Drugs
Medicinal
Drugs- Used to
control disease
and can only
be prescribed
by a doctor
Recreational Drugs-
Used only for
pleasure and affect
the brain and
nervous system
Recreational drugs
can be legal like
caffeine or alcohol or
illegal like cannabis
or heroin
Impact of legal
drugs greater
than illegal
drugs as they
are more readily
avaliable
Does
Cannabis
Lead to
Hard Drugs?
Obtaining
cannabis
from dealers
may put
people in
contact
with harder
drugs
Chemicals
in
cannabis
can cause
mental
illness
particularly
in
teenagers
Drugs
in
Sport
Some
athletes use
illegal
performance
enhancing
drugs such as
steroids to
give them an
unfair
advantage in
competitions
Most
would
consider
this
unethical
Adaptation
and
Survival
Adapt and
Survive
Organisms
get
necessary
materials for
survival from
their
surroundings
and other
organisms
Organisms
are
adapted to
survive in
the
conditions
they
normally
live
Some
microorganisms,
extremophiles,
are adapted to
live in the most
extreme
environments
Adaptation
in Animals
Adaptations
help an
animal
survive
Animals in cold climates are usually large with small surface
area: volume ratio, and vice versa for hot climates
Coat
colour may
to provide
year round
camoflage
Adaptation
in Plants
Plants lose water vapour
from stomata on the leafs
surface
To
conserver
water
plants
reduce the
surface
area of
leaves,
store
water and
have
extensive
root
systems
Competition
in Animals
Animals compete
for: food, water,
territory and
mates
The best
adapted
animals are
good
competitors
Competition
in Plants
Plants
compete for:
water, light,
space and
nutrient and
mineral ions
from the soil
How do
you
survive?
Measuring
Environmental
Change
Environmental
changes the
distribution of
organisms
Changes can
be caused by
living factors,
arrival of a
new predator
or disease, or
non-living
factors,
temperature
and rainfall
Environmental changes
can be measured with
using non living indicators
such as thermometers or
rain gauges
Organisms,
indicator species,
can used to
disclose pollution
levels
Impact of
Change
Distribution
of organisms
can be
affected by
living and
non living
factors
Data on the
effect of
environmental
change isn't
always easy to
interpret
Energy
in
Biomass
Pyramids
of Biomass
Main source
of energy for
organisms is
the sun's
radiation
Green plants turn
the light energy to
chemical energy
during
photosynthesis
Biomass- Amount
of dry living mass
in an organism
Biomass at
each stage of
the food chain
is less than the
previous stage
Energy
Transfers
Less energy is
available at each
stage of the food
chain as it is lost
through
movement,
waste and into
the surroundings
The
rest is
used
for
growth
Decay
Processes
Organisms
take nutrients
from the
environment
which are
returned
when they die
Decay is started by detritus
feeders who produce waste
materials that are then
eaten by microorganisms
called decay organisms
Decay
happens
quicker in
warm
moist
aerobic
conditons
Carbon Cycle
Carbon
cycle is
the
constant
recycling
of carbon
in nature
Carbon dioxide
is removed from
the
atmosphere
during
photosynthesis
Respiration
and
combustion
return
carbon
dioxide to
the
atmosphere
Recycling
Organic
Waste
Recycling
organic
waste
reduces
landfill and
methane,
and recycles
nutrients in
the waste
Variation,
Reproduction
and New
Technology
Inheritance
Offsprings have
similar
characteristics to
their parents
Genes are
passed in
gametes
from parents
to
offsrprings
Genes control
characteristics
of your body
Types of
Reproduction
Clones are produced
during asexual
reproduction, where no
gametes join
Clones-
Genetically
identical
copies of one
parent
Sexual reproduction
involves the joining
of gametes from two
parents leading to a
variety of offsprings
Genetic and
Environmental
Differences
Difference within a
species can be because
of genetic factors due
to differences in the
genes they have
inherited, and
environmental factors
such as diet and
exercise
Clones may
have differences
due to
environmental
causes
Cloning
Plant
clones
can be
made
quickly
and
easily by
making a
cutting
A tissue
culture
could be
made by
taking
some cells
from the
plant and
growing
them in
special
conditions
Animals
can be
cloned by
putting a
nucleus in
an empty
egg and
placed in a
surrogate
mother
Adult Cell
Cloning
Scientists
have used
adult cell
cloning to
clone
animals
such as
Dolly the
sheep
The nucleus
of a cell is
placed into
an empty
egg cell and
transplanted
in to a host
mother,
creating a
clone
Genetic
Engineering
Genetic
engineering
transfers a gene
for one
organism to
another to give
a desired
characteristic
Enzymes are
used to cut a
gene from a
chromosome
and is then
inserted in
another
Genes must
be transferred
at an early
stage of
development
Making
Choices
About
Technology
Disadvantages
Long
term
affects
of
eating
GM
crops
aren't
known
Could reduce or
contaminate
the gene pool
'Playing'
God
Advantages
May
provide
cures for
genetic
disorders
Produces
medical
drugs
Crops are
resistant to
herbicides and
insects
Evolution
Theories
About
Evolution
It is thought all
life developed
from simple
organisms that
lived 3 billion
years ago
Darwin
suggested
evolution takes
place by a
process of
natural selection
over many years
Accepting
Darwin's
Ideas
Darwin's
theory was
only
gradually
accepted
Natural
Selection
Natural
selection
means the
fittest
organisms
survive to
breed
If a gene
mutates the
new
characteristics
may allow and
organism to
survive better
Classification
and
Evolution
Comparing
similarities
and
differences
allow
classification
of organisms
Classification
allows
evaluation of
evolutionary
relationships