ALCOHOL -
Decrease activity of
the brain. Slows
down response of
the nervous system
& poor judgement
Stimulants
NICOTINE/CAFFINE -
Increase activity of
the brain & increase
neurotransmitters.
Makes you feel more
alert & awake
Painkillers
MORPHINE - decrease
feeling pain. Work in
different ways such as
morphine blocks the
nerve impulses of the
brain
Hallucinogens
LSD - Distort
whats seen & heard
by altering
pathways nerve
impulses take
REACTION TIME - is
how quickly you
respond to a
stimulus - can be
tested by the ruler
drop test
Smoking, Alcohol
& Transplants
Smoking
Tabacco smoke contains carbon
monoxide, which combines with
the hemaglobin in the red blood
cells causing less oxygen to be
carried. In pregnant women it can
deprive the feutos of oxygen
causing it to be born underweight
Tabacco smoke also
contains carginogens
like tar. Lung cancer is
much more common in
smokers & is addcitive
Alcohol
Slows down reactions as
it a depressent & blurred
vision and lower
inhibitions leading people
to do this they normally
wouldnt
Its poisonous. Usually the liver
removes it but drinking often
liver cells can die forming
sscar tissue which blocks
blood flow - Chirrosis of the
liver & also brain damage
Transplants
Organs that have been
damaged can be replaced. Living
donors can donate one of their
kidneys or a peice of their liver
People who are willing to donate can do so or
use organs when youve died. People think if
youve dameged your own organ you dont
deserve a new one
Because of the shortage
often people have to
change their lifestyle to be
considered. E.g Loosing
weight & prove you can
stop drinking
Infectious diseases
Pathogens are micro-organisms
that cause disease (germs)
Water
Picked up by drinking
dirty water. E.g cholara
causing diheroea &
dehydration
Food
Eating contaminated
foods. E.g salmonella
causes food poisoning
due to uncooked food
Air
Carried by droplets
in a sneeze or cough
so other people can
breathe them in. E.g Flu
Contact
Contaminated surfaces
including skin. E.g
athletes foot carried by
touching the same as
someone infected
Body fluid
Such as blood E.g
sharing needles
Animal Vectors
Mosquito carry protozan that
causes malaria damaging the
brain. House fly causing
dynestry - dhiarreo
Physical Barriers
THE SKIN clots
quickly if it gets
damaged to stop
microorganisms
getting in
THE RESPIRITORY STYSTEM - is lined
with cillia and mucus. Mucus catches
the dust before reaching the luns and
mucus pushes it away from the lungs
Chemical Barries
THE EYES in tears produce
lysozyme which kills bacteria on
the surface of the eye
THE STOMACH kills bacteria
with the hydrochloric acid
Plants can defend
themseves
When plants are attacked
by pathogens they release
chemicals to defend
themselves
Some of these have
antibacterial effects,
humans can use these
plants to help them too
E.g TEA TREE is an
australian shrub that
produces oil killin bacteria.,
this is used for antibacterial
products like face clensers
ANTISEPTICS
Destroy bacteria/stop them
growing. Used outside of the body
to clean wounds & surfaces.
Prevent infection instead of treat
it
Used in household producs eg
bathroom cleaners & in
hospitals to prevent infection
ANTIBIOTIC
ANTIBACERIALS
E.g penacillin used to teat
bacterial infections. They kill
bacteria & stop them growin
ANTIFUNALS
E.g nystatin used to treat
funal infections. They kill
the fungi & stop it growing
Drugs used inside
the body & treat
people already
infected but doesnt
kill the virus
Antiseptics &
Antibiotics
1) Bacteria can mutate,
this sometimes causes
them to be resistant to
an antibiotic.
2)When you take the antibiotic only
the non resistant bacteria will die,
the rest will continue to live and
reproduce & the resistant population
will increase (natural selection
3) Resistant strains
could cause serious
infections such as MRSA
that cannot be killed by
antibiotics
4) Doctors overprescribing
or not finishing the course
of antibiotics has resulted
in many more resistant
strains. so wont get any
antibiotics for a casual cold
Energy &
Biomass
1) Energy from the
sun is the source of
energy for nearly
everything on earth
2) Plants convert a small % of light energy
into glucose. The rabbit then eats the plant &
uses some of the energy it gets, the rest is
stored. Then the fox eats the rabbit & gains
energy (The food chain)
3) Energy is used up to stay alive
(respiration) alot of energy is lost
to surroundings as they keep a
constant temperature
4) The energy is said to be
lost (its still there it just cant
be used by the next animal
5) Energy is also
lost in droppings
6) This is why a food chain doesnt
have more than 5 trophic levels. So
much energy is lost theres not
enough left to support them
1) Biomass is how much
the creatures would weigh
if they were put together
2) Each time you go up a tropic
level - E.g the producer is eaten
by the consumer, the weight of
the consumer will be less than
that og the producer
Paratism &
Mutualism
Patatism
Fleas
Live of the fur of
animals and suck their
blood & can reproduce
Head lice
Live on humans
scalps & suck
blood
Tapeworms
Attatch themselves to
the intestine wall of
their host & absorb
their nutrients causing
malnutrition
Mistletoe
A plant that absorbs
water & nutrients from
its host reducing
growth
LIVE ON THE
HOST & GETS
NO BENEFIT
Mutualism
Oxpeckers
Live on buffalo, they eat
pests of the buffalo & its a
source of food for them and
alert them of predators
(cleaner species)
Cleaner fish
Eat dead skin and paracites
of larger fish & so they get
food
Nitrogen Fixing
Bacteria in legumes
They carry the bacteria in the
nodules of the roots. The bacteria
gets a constant supply of sugar &
the plants get nitrates
Chemosynthic
bactreria
Live in giant tube worms. The tube worms
supply the bacteria with chemicals which the
bacteria turn into food for them & the host
BOTH
BENEFIT
Human Activity &
the environment
The population continues to rise,
mostly due to modern medicines
that stop disease from spreading
& modern farming methods that
can produce enough food for
everyone
This means that
non-renewable
recourses are
being used
More & more
waste is being
produced
More and more
pollutants are being
produced... Phosphates,
nitrates and sulphur
dioxide
Eutrophication
1) Fertilisers containing nitrates are
essential to modern farming, without
them crops wouldnt grow as well and
food yield would be down ThThis is
because crops take out nitrates from the
soil and it needs to be replaced
Excess nitrates are
washed into the rivers
causing a rapid growth
of algea
Some plants start dying
due to the little light thats
gained as its blocked by the
excess algea
Number of
microbes increase
as they feed on the
dead materials
Oxygen cant be produced as plants
cant photosynthesis and the
oxygen there is is used up by the
microbes & so fish sufficate & die
Recycling
Recycling conserves our
natural recourses meaning the
amounts of non-renewable
recources wont decrease
If materials arent recycled theyre
thrown a way as waste. There is
more waste so more land is used
as landfill & can add polution
from toxic waste
More materials have to be
manifactured or extracted to
make new products in stead of
reusing them
METALS - extracted by there ore, there is
a limited amount avaliable, we have to
mine for ores too usually releacing CO2
PAPER - producted from wood, recycling
means that less trees have to be knocked
down which stops deforistation
PLASTICS - most made by crude oil, so recycling helps
to reserve oil resources. They also take ages to
decompose, so theyd fill up landfill
Problems
Recycling
1) Still uses energy,
collecting sorting ect
2) Can be time consuming
to sort, eg plastics
3) The equiptment
is expensive
4) Sometimes the quality isnt
as good as new materials
5) Some things can only be recycled
a certain num,ber of times eg paper
Indicator
species
Organisms that are sensitive
to changes in their
environment that can be used
to monitor human activity
Water Pollution
1) If raw sewage or other pollutants
containing nitrates are released into
a river the bacteria population will
increase & use up oxygen
2) STONEFLY LARVAE & FRESHWATER SHRIMPS
are good indictators as theyre sensitive to the
concentration of disolved oxygen. IF YOU FIND
THEM, THE WATER IS CLEAN
3) BLOODWORM & SLUDGE WORN indicate HIGH
levels of pollutuion, theyve adapted to live there
Dissolved oxyem meters &
chemical tests also measures
dissolved oxygen
Air pollution
1) LITCHEN is very sensitive to concentartion
of SULPHUR DIOXIDE, the MORE the litchen in
one area the CLEANER the area
2) BLACKSPOT FUNGUS on roses are
also sensitive to the SULPHUR
DIOXIDE. also shows CLEAR AIR
3) ouside the city theres less sulphur
dioxide in the air and so less litchen
1) The ONLY thing that gets rid
of CO2 is PHOTOSYNTHESIS-
plants use it to make proteins
2) Animals eat the
carbon compound in
the plants & passes
along the food chain
3) Plants &
Animals RESPIRE
and PUT CO2
INTO THE AIR
4) Plants & Animals eventually DIE
& DECAY, when they do there broken
down by BACTERIA & FUNGI. These
decomposes add C02 to the air
5) FOSSIL FUELS are
burned and release CO2
into the air
The Nitrogen Cycle
1) Nitrogen is about 78% of
the atmosphere, its very
unreactive so cant be used
directly by plants. Nitrogen is
needed to make proteins so
they have to get it somehow
2) Nitrogen has to be turned
into compound eg NITRATES.
Plants can absorb nitrates
from the soil to make the
proteins. Animals get the
protein by eating the plants so
its passed along the food chain
3) DECOMPOSERS
(bacteria, fungi) in the soil
breaks down dead plants
and animals, turning their
proteins and urea into
AMMONIA
4) Soil bacteria - NITRIFYING BACTERIA
turns AMMONIA INTO NITRATES &
Nitrates can be taken up by the plants
5) NITROGEN FIXATION
turns NITROGEN into
NITRATES - by LIGHTNING &
NITROGEN FIXING BACTERIA
DECOMPOSER BACTERIA -
decomposes PROTEINS & UREA
into AMMONIA
NITRIFTYING BACTERIA - turn
AMMONIA in decaying matter
into NITRATES
NITROGEN-FIXING
BACTERIA - turns
NITROGEN into
NITRATES
DENITIFYING BACTERIA - turns
NITRATES back to NITROGEN - no
help for living things