Download B1 fact sheet missing words with letters

B1 Biology fact sheet
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Sense organs detect s…………………………………….. – a change in your environment
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E…………………………………….. contain light receptors
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Ears contain s…………………………………….. and b…………………………………….. receptors
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Nose contains s…………………………………….. and t…………………………………….. receptors
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Tongue contains t…………………………………….. receptors
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Skin contains t…………………………………….., t…………………………………….. and p…………………………………….. receptors
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The CNS is made up of the b…………………………………….., spinal cord and n……………………………………..
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N…………………………………….. (nerve cells) transmit information to and from CNS
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S…………………………………….. neurones carry impulses from receptor  CNS
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Relay neurones connect s…………………………………….. and m…………………………………….. neurones
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M…………………………………….. neurones carry signals from CNS  effectors (m…………………………………….. or
g……………………………………..)
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Reflex arc - stimulus  r……………………………………..  s…………………………………….. neurone  relay neurone 
motor neurone  e……………………………………..  r……………………………………..
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2 neurones are connected by a s…………………………………….., a gap across which chemicals d……………………………………..
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Hormones are chemical m…………………………………….. carried in the blood to activate target cells
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Menstrual cycle has f…………………………………….. stages
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1) DAYS …………………………………….. Lining of the womb breaks down – bleeding
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2) DAYS …………………………………….. Lining of womb builds back up again
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3) DAY …………………………………….. Egg is released
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4) DAYS …………………………………….. Lining of the womb is maintained
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FSH – f…………………………………….. s…………………………………….. hormone
– produced by p…………………………………….. g……………………………………..
- causes an e……………………………………..……………………………………..……………………………………..
- stimulates ovaries to produce o……………………………………..
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Oestrogen
- produced in ovaries
- causes p…………………………………….. g…………………………………….. to produce l……………………………………..
- stops release of F……………………………………..
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LH – l…………………………………….. hormone
- produced by pituitary gland
- stimulates releases of e……………………………………..
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Fertility hormones can be used to either i…………………………………….. or d…………………………………….. fertility
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Reducing fertility. Oestrogen used in the c…………………………………….. pill which prevents the release of an egg
by stopping release of F……………………………………..
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Increasing fertility. F…………………………………….. taken to stimulate egg production. Eggs can then be collected
for IVF.
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IVF – I……………………………………..……………………………………... Eggs collected from o…………………………………….. and
fertilised with a s…………………………………….. in a lab. Electric shock provided to stimulate cell growth. Eggs then
implanted back into uterus, in attempt to implant.
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H…………………………………….. – maintaining a constant internal environment
- I…………………………………….. c…………………………………….. – taken in through food, lost through sweat, regulated by
the kidneys, removed via urine
- w…………………………………….. – taken in through food & drink, lost from body by sweat, breath & urine. On cold
days sweat less & produce more urine. On hot days sweat more & produce less urine
- b…………………………………….. t…………………………………….. – controlled by brain and skin. Body temperature kept at
37oC.
- b…………………………………….. s…………………………………….. – controlled by hormone insulin produced by the pancreas.
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A…………………………………….. is a plant hormones that control growth
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Auxin controls the growth of plants in respond to tropisms
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Phototropism is the response to l……………………………………..
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Geotropism is the response to g……………………………………..
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Hydrotropism is the response to w……………………………………..
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Auxin is made in the tip of the s…………………………………….. and the r…………………………………….. of a plant
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Shoot tips will grow towards l…………………………………….. as more auxin is produced on the side away from the
light source
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Shoot tips will grow away from g…………………………………….. as more auxin is produced on the lower side of the
shoot
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Roots grow towards g…………………………………….. as more auxin is produced on the lower side of the shoot
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Roots grow towards m…………………………………….. as more auxin is produced on the side near the water source
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Plant hormones can be used as w…………………………..…………………….. and r…………….……………………………………..
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Balanced diet contain
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c…………………………………….. for energy
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fats for s……………………………………..……………………………………..
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protein for g…………………………………….., cell r…………………………………….. and replacement
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fibre for regular d…………………………………….. s……………………………………..
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m…………………………………….. & v…………………………………….. for a healthy body
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The m…………………………………….. rate is the speed at which chemical reactions happen
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Metabolic rate depends on
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m…………………………………….. to f…………………………………….. ratio, more muscle needs more energy = high m.rate
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a…………………………………….. level, more active need more energy = high m.rate
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i…………………………………….. factors
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Eating too much can lead to o……………………………………..
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Obesity can cause problems with a…………………………………….., high b…………………………………….. pressure,
d…………………………………….. and h…………………………………….. disease.
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Eating too little can lead to d…………………………………….. diseases
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C…………………………………….. is a fatty substance made in the liver and carried in the blood.
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It is needed for good health, but too much can be bad
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S…………………………………….. fats raise cholesterol. P…………………………………….. fats lower cholesterol
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Too much s…………………………………….. causes high blood pressure
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D…………………………………….. are any substance that alters your body chemistry
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P…………………………………….. enhancers are taken by some athletes to make them better
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S…………………………………….. are a prescribed drug given to lower heart & circulatory disease
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There is evidence that statins have lowered blood cholesterol and lower the risk of heart disease in
diabetics,
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This research has been repeated by others which backed up findings and the study was done on a large
sample
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C…………………………………….. is an illegal drug.
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Scientists looked at whether cannabis smoke caused mental health problems.
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The results varied between test so no conclusive evidence is available.
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New medical drugs have to be tested thoroughly before they can be given to the general public
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There are 3 stages of drug testing
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Drugs tested on h…………………………………….. c…………………………………….. and t…………………………………….. in labs
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Drugs tested on live a…………………………………….. to see if drug works, research its toxicity and to find the best
dosage
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Drugs tested on h…………………………………….. in clinical trials. First on healthy volunteers to find optimum dose.
Then drug is given to i…………………………………….. patients that have been split into 2 groups a) given new drug b)
given a p…………………………………….. (no effect tablet) and results are compared. Placebo trial are
“b……………………………………..” so pateints don’t know if they are getting the drug or not
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T…………………………………….. was a sleeping pill that was prescribed to pregnant women to help with
m…………………………………….. s……………………………………... It hadn’t been tested and affected the foetus and caused
stunted growth of limbs. The drug was banned but is now used for l……………………………………...
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Tobacco smoke contain c…………………………………….. monoxide which makes the blood carry less
o……………………………………... It also contains carcinogens that cause cancer. N…………………………………….. is the addictive
part of cigarettes
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A…………………………………….. reduces the activity of the nervous system – leading to impaired judgement, poor
balance and coordination, lack of self control and unconsciousness
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Cannabis is known as a g…………………………………….. drug – the effects create a desire to try harder drugs
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Any microorganism that causes a disease is known as a p……………………………………..
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Bacteria are very small cells that damage cells and produce ……………………………………..
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Viruses are not c…………………………………….., they contain a DNA strand surrounded by a protein coat. They
replicate themselves inside another cell. The cell damage makes you feel ill.
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White blood cells have 3 defence mechanisms
1) WBC e…………………………………….. microbes
2) WBC begin to produce a…………………………………….. to kill invading cells
3) WBC produce a…………………………………….. to counter poisons produced by invading bacteria
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I…………………………………….. protects from future invasions by injecting dead or inactive microorganisms. These
contain antigens which make body produce antibodies. If live microorganisms appear after injection WBC can
rapidly produce antibodies to kill off pathogen.
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P…………………………………….. relieve pain. They tackle the symptoms not the cause of disease
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A…………………………………….. kill the bacteria without killing body cells
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B…………………………………….. cannot be treated by antibiotics, only the symptoms can be treated.
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Bacteria can become r…………………………………….. to antibiotics if they are continually exposed to the same ones,
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S…………………………………….. cut deaths by making doctors in hospitals use antiseptics between patients.
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V…………………………………….. help to prevent diseases
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Desert animals are adapted to save water
- l…………………………………….. surface area compared to volume to ose more body heat
- produce small amounts of concentrated urine & little sweat– conserves water
- t…………………………………….. layer of body fat to help lose body heat
- large f…………………………………….. spread weight across soft sand
- sandy colour gives c……………………………………..
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A…………………………………….. animal are adapted to reduce heat loss
- small surface area compared to v……………………………………..
- thick layer of blubber & thick hairy coat for insulation
- g…………………………………….. fur sheds water
- w…………………………………….. fur for camouflage
- big feet to spread weight
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C…………………………………….. are adapted to live in a deserts
- have spines instead of leaves to reduce water loss
- small surface area compared to size to reduce water loss
- stores water in thick stem
- have shallow extensive roots to absorb water quickly
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A p…………………………………….. is a group of organisms of one species that live in a habitat
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Population sizes are affected by c…………………………………….. (space, food, water, mates), disease, predation
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Competition
- plants - l…………………………………….., w…………………………………….., s…………………………………….. & n……………………………………..
- animals – t…………………………………….., f…………………………………….., w…………………………………….. & m……………………………………..
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Human impact can be measured using i…………………………………….. species. Organisms that are sensitive to
changes in their environment can be studied to see the effect of human activities
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L…………………………………….. can be used to monitor changes in air pollution as they are very sensitive to the
levels of sulphur dioxide
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M…………………………………….. can be used to monitor water pollution, can’t live where not much oxygen in water
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S…………………………………….. can be used to monitor water pollution, live where there is not oxygen in water
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Variation – differences between organisms of the same species
- g…………………………………….. – caused by inherited genes
- e…………………………………….. – caused by surroundings
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Food chains show the e…………………… t…..……………….. between feeding levels (trophic levels)
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L…………………………………….. energy get passed along at each stage of the food chain – energy lost through
r…………………………………….., m…………………………………….., h…………………………………….. & w……………………………………..
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There is less biomass at each stage in the food chain
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P………………………..…………………………………….. represent the food chain
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Materials are recycled by decay
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M…………………………………….. break down (decompose) materials and work best in warm, moist conditions with
lots of O2
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The carbon cycle shows the recycling of carbon in the atmosphere.
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P…………………………………….. removes carbon from the atmosphere
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R…………………………………….., c…………………………………….., volcanoes all return carbon to the atmosphere
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Variation is the differences between species caused by
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g…………………………………….. e.g. blood group
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e…………………………………….. e.g colour of plant leaves
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b…………………………………….. e.g height of sunflower
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Most characteristics are due to a mixture of both
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Genetic material is contained in the n…………………………………….. of a cell.
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The nucleus contains 23 pairs of c……………………………………..
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Chromosomes carry g…………………………………….. which control the development of different characteristics
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A gene is a short length of a chromosome
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DNA is coiled up to form the arms of a chromosome
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Cells can reproduce to make new cells
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A…………………………………….. reproduction produces genetically identical cells. There is only one parent cell and
the 2 offspring have identical genes to the parent
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S…………………………………….. reproduction produces genetically different cells. There are 2 parent organisms and
genetic information is combines to produce offspring. The gametes (sperm & egg) each contain 23 chromosomes
and fuse together to produce a cell with a full set of chromosomes
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Asexual reproduction can be used to clone a…………………………………….. and p……………………………………..
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Plants can be cloned from cuttings and tissue culture
- c……………………………………... Cutting taken from parent plant, quickly produces identical offspring
- t……………………………………... Few plant cells placed in growth medium with hormones, grow into new plants.
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Animals can be cloned using e…………………………………….. transfer or a…………………………………….. cloning.
- embryo transfer. Sperm from male & egg from female. Developing embryo is split to form clones before
cells specialise. Cloned embryos implanted into surrogates. Offspring are all genetically identical to each other,
but not the parents
- adult cell cloning. The nucleus is removed from an egg cell. A set of chromosomes from the cell of another
adult are inserted into the empty egg. This egg cell then grows into an embryo and is implanted into a surrogate.
The offspring is genetically identical to the original adult whose chromosomes were used.
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G…………………………………….. uses enzymes to cut and paste genes from one organism to another.
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Genes can be transferred into animals and plants
- GM crops have been developed to be resistant to viruses and herbicides
- Human insulin genes have been inserted into bacteria to produce human i…………………………………….. for
diabetes sufferers
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The theory of evolution states that life on Earth began as simple organisms that have evolved into more
complex organisms over millions of years
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The f…………………………………….. records show that organisms have evolved
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If organisms can’t evolved they become extinct. The 3 main reasons for extinction are
- the h…………………………………….. changes too quickly
- a p…………………………………….. or d…………………………………….. kills them
- they can’t c…………………………………….. with another species
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D…………………………………….. came up with idea of Natural Selection which states that species are well adapted
to the environment that they live in. The better adapted an organism is the better its chance of survival and
chance to pass on its genes  Survival of the fittest.