Zusammenfassung der Ressource
B1
- Fitness and Health
- Low blood pressure: -
Dizziness - Fainting -
Poor circulation
- High blood pressure: -
Blood vessels burst -
damage to brain (stroke)
- damage kidneys
- Can be increased by stress, alcohol,
smoking, being overweight
- Can be decreased by regular exercise and a
balanced diet
- Blood pressure is measured in mm of mercury
(mmHg)
- Systolic Pressure; maximum pressure the heart
produces
- Diastolic pressure; the pressure between
heart beats
- Fitness is the ability to do
physical activity
- Can be measured by Strength, Flexibility, Stamina,
Agility, Speed
- Health is being free from diseases
- Smoking
- Carbon Monoxide in cigarette smoke decreases the oxygen-carrying
capacity of blood as it combines with haemoglobin, preventing it from
combining with oxygen so less is carried.
- Heart disease is caused by a restricted
blood flow to the heart muscle.
- Increased by: high levels of saturated fat, which
leads to building up cholestrol
- Narrowing of arteries
caused by plaques in
the coronary arteries
can reduce blood flow
to the heart muscle. Also
makes blood clots or
thrombosis, which will
also block the artery.
- Human Health and Diet
- Carbohydrates- Simple sugars such as
glucose
- Stored in the liver as glycogen/converted into fats.
- Proteins- Amino acids
- Can't be stored in the body but are
used to repair and for growth
- EAR in g = 0.6 x body mass in kg
- Depends on certain factors; body mass, age,
pregnancy or breast feeding,
- Too little protein can
cause Kwashiorkor which
is popular in LEDC'S due
to lack of money to buy
food.
- First class proteins
- Meat and Fish.
Contain Amino
Acids which can't
be made by the
human body.
- Second class
proteins - Plants
proteins. Don't
include all of the
Amino Acids.
- Fats-Fatty acids and glycerol
- Stored under the skin/around organs.
- Balanced diet varies according to
specific factors. Whether its your age,
gender, level of activity, religion,
vegetarian/vegan, or medical
issues/food allergies
- BMI = mass in kg / (height in m)2
- More than 30:Obese. 25-30:Overweight
20-25:Normal. Less than 20:
Underweight
- Staying Healthy
- Malaria
- Caused by protozoan called
Plasmodium(parasites), which feeds on human red
blood cells.
- Mosquito- Carries Plasmodium and is the vector,
where as us humans are the host. It releases the
Plasmodium into our bodies, which travels to our lungs
and bursts our red blood cells.
- Treatments - draining stagnant water,
putting oil on it's surface and spraying
insecticide to stop the mosquitoes life
cycle
- Cancer
- not smoking - prevents
risk of skin cancer
- Wearing suncream-
prevents risk of skin
cancer
- Benign tumour cells (in
warts) divide slowly and are
harmless
- Cancers are malignant
tumours; the cells have
uncontrolled growth and
may spread
- Pathogens(cause diseases)
destroy the body cells or
produce poisionous cells
called Toxins.
- The body protects itself by producing antibodies
from the white blood cells resulting in active
immunity
- The antibodies protect us by locking onto
antigens which are on the surface of Pathogens
and kills them
- Each Pathogen has it's own Anitbody
- Vaccinations
- Injecting a harmless
pathogen which is carrying
antigens. The antigens
trigger the white blood
cells which then sends out
correct antibodies.
- Memory Cells
(T-lymphocyte cell) remain
in the body which provides
immunity against that
disease.
- Tested on
animals, human
tissue and
computers
beforehand
- An antiviral drug slows down the Pathogens development
- Trials
- Blind trial, the patient
doesn't know whether
they're receiving a drug
or a placebo. Avoid a
'feel- good factor' and a
biased opinion.
- The nervous system
- How do eyes work?
- Light rays are refracted (bent) by the cornea and the lens.
- Binocular vision helps to judge
distance by comparing the
images from each eye, the
more different that they are, the
nearer that the object is.
- Accommodation -
Focusing light from
distant or near objects
by altering the shape of
the lens.
- When focusing on distant objects, the
ciliary muscles relax and the
suspensory ligaments tighten so the
lens has a less rounded shape.
Vise-versa for focusing on near objects.
- Faults in vision
- Red- green colour
blindness is caused
by a lack of
specialised cells in
the retina
- Long sight - the eyeball is too
short or the lens is too thin, so
the image is focused behind the
retina
- Convex lens
- Short sight - the
eyeball is too long
or the lens is too
rounded so the
lens refracts light
too much so the
image would be
infront of the retina
- Concave lens
- Nerve Cells
- Nerve cells are
called neurones.
Nerve impulses
pass along the
axon.
- Reflex action is show by a reflex
arc. Stimulus-Receptor-Sensory
Neurone-Central Nervous
System-Motor
Neurone-Effector-Respone
- Spinal reflex; Receptor-Sensory
Neurone- Relay Neurone-Motor
Neurone-Effector
- Gap between neurones is
called a synapse,
- Drugs and you
- Types of drugs
- Depressants- Alcohol, Solvents, Temazepam
- Block the transmission of nerve
impulses across synapses by
binding with receptor molecules in
the membrane of the receiving
neurone.
- Painkillers- Aspirin, Paracetamol
- Stimulants- Nicotine, Ecstasy, Caffeine
- Cause more
neurotransmitter
substances to
cross synapses.
- Performance enhancers- Anabolic steroids
- Hallucinogens- LSD
- Effects of smoking
- Smoke contains many
chemicals that stop cilia
moving.
- Cilia-tiny hairs
found in
epithelial lining
of trachea,
bronchi and
bronchioles
- Smokers cough- dust and
particulates in smoke irritating the
epithelial lining and mucus not
being moved by the cilia.
- Effects of alcohol
- Increases
reaction
times and
risk of
accidents
- Cirrhosis of the
Liver- Liver is
damaged when
it breaks down
toxic chemicals
such as alcohol.
- Staying in balance
- Homeostasis
- Definition- Keeping a
constant internal
environment
- Involves balancing bodily inputs and outputs
- Automatic control system keeps the
levels of temperature, water and carbon
dioxide steady
- Negative feedback controls are
used in it. Act to cancel out a
change such as decreasing
temperature level.
- Temperature control
- Normal body temp: 37 degrees celscius
- High temp can cause: heat stroke, dehydration
- Low temp can cause: hypothermia
- Blood temp is monitored by the hypothalamus
gland in the brain. Reaction to temp extremes
are controlled by the nervous/hormonal
systemss which trigger
vasoconstriction/vasodilation
- Vasoconstriction -
Narrowing of small blood
vessels in skin. Causes
less blood flow/less heat
transfer.
- Vasodilation- widening of small blood vessels in skin.
Causes more blood flow near the skin surface resulting in
more heat transfer
- Control of blood sugar levels
- Insulin- hormone, control blood sugar levels
- Converts excess glucose in the blood into glycogen, stored in liver
- Type 1 diabetes- Pancreas not producing
any insulin, must be treated by insulin
- Insulin varies
according to the
persons
diet/activity. Big
effort of exercise
needs more glucose
to be in the blood,
so lower insulin is
then required.
- Type 2 diabetes- Body producing little
insulin or body not reacting it, can be
controlled by diet
- Controlling plant growth
- Plant responses
- Phototropism - a plant's growth response to light.
- Geotropism - a plant's growth response to gravity.
- Shoots are positively phototropic and grow
towards the light, and are also geotropic as
they grow away from the pull of gravity.
- Roots are negatively phototropic and positively geotropic.
- Plant hormones (auxins)
- Auxins- group of plant hormones, more through the plant in solution
- They are involved in phototropism and geotropism
- Different amounts
of auxins are found
in different parts of
the shoot when the
tip is exposed to
light. Auxin is
mostly found in the
shady parts of the
shoots.
- Higher amount of
auxin = increased
length of cells
- Therefore,
an
increased
amount of
cell length
on the
shady side
causes for
the shoot to
curve
towards the
light
- If tip is removed, will not grow
- Uses
- Used as a selective weed killer, which kill
specific weeds and increase the crop yield
- Root powder to increase root growth of cuttings
- Delay fruit ripening to meet market demands
- Control dormancy in seeds
- Variation and inheritance
- Inherited characteristics
- Inherited characteristics can be dominant or recessive
- They depend on dominant and recessive alleles
- Dominant alleles- expressed when
present
- Recessive alleles- only in the absence of the
dominant allele.
- Alleles- different versions of the same gene
- Chromosomes
- Human cells have 23 pairs.
- Female - XX
- Eggs only carry X chromosomes
- Male - XY
- Sperm carries either X or Y chromosomes
- Random chance - equal chance of the offspring being male or female
- Genetic variation
- Caused by
- Mutations -
random changes
in the genes or
chromosomes
- Rearrangements of genes during the formation of gametes
- Fertilisation - zygote
with alleles from father
and mother
- Monohybrid cross
- Involves 1 pair of
characteristics
controlled by a
single gene, one
allele being
dominant and the
other being
recessive
- Homozygous - identical alleles
- Heterozygous- having different alleles
- Genotype - genetic make up
- Phentoype - alleles are expressed
- Inherited disorders
- Caused by faulty alleles, mostly recessive
- Possible to
predict the
probability of
inheriting such
disorders by
interpreting
genetic
diagrams.