Download B1 exam: Key words to understand

B1 exam: Key words to understand
There are lots of new key terms that you need to make sure you understand in preparation for your exam. It’s really
important that you recognise what each of the words mean and are able to use them correctly in a sentence. This
will help you to explain ideas scientifically and ensure you pick up important marks in your exam.
Some tips for learning science vocabulary.
Tip 1 -Play some games with the keywords
You could play hangman with your friends or family using the words you need to learn. Make sure you explain what
the word means when they have guessed it.
You could play Pictionary for some of the energy types or renewable energy sources. Ask someone to draw you a
picture for one of these terms and see if you can guess which one they are drawing.
Tip 2 – Use flash cards
Write out the key word and the definition on separate cards, mix them up and see if you can match the keyword
with the correct description.
Write the keyword on one side and the definition on the other. Look at the keyword side and see if you can
remember the definition or read the definition and try to remember the keyword. Turn the card over to check, or
ask someone else to read them out to you.
See if you can sort the keywords into groups of similar words. For example, you could group together all the words
that give a different type of energy. Try to explain why you have grouped them together to a friend or family
member.
Tip 3 – Spelling strategies
Use the spelling strategies that you talk about in tutor time to help with any words that you find difficult to spell.
Break it into sounds
Break it into syllables
Break it into word parts
Use a mnemonic
Refer to word in the same family
Say it as it sounds
Words within words
Make connections between words
Think about the meaning of words
Apply spelling rules
Learn by sight
(d-i-a-r-y)
(re-mem-ber, con-tin-ent)
(dis+satisfy)
(necessary—one collar, two sleeves, rhythm has your
two hips moving)
(muscle—muscular)
(Wed-nes-day)
(Parliament—I AM parliament, GUM in argument)
(bright, light, night, etc)
(bi+cycle = two+wheels)
(writing, written)
(look—cover—write—check)
Key term
Kingdom
Unicellular
Multicellular
Nucleus
Autotrophic
What it means
The highest level used to classify organisms
Single-celled organism
Organism made of many cells
Contains the chromosomes, which carry genes to control the
activities of a cell
Makes its own food (i.e. plants)
Heterotrophic
Feeds by eating and digesting other organisms (i.e. animals)
Saprophytic
Feed by digesting organisms outside of the body (i.e. fungi)
Virus
Chordata
Invertebrates
A microorganism that doesn’t fit into a kingdom as scientists don’t
think of them as being alive.
The phylum to which all vertebrates belong
Animals that do not have a backbone
Oviparous
Lays eggs
Viviparous
Gives birth to live young
Homeotherms
Control their own body temperature
Poikilotherms
Body temperature varies with the surroundings
Internal fertilisation
The sperm and egg fuse inside the body
External fertilisation
The sperm and egg are released into the water before fertilisation
occurs
Fertile
Species
Hybrids
Ring species
Binomial system
Adaptations
Variation
Biodiversity
Able to reproduce
A group of organisms that can interbreed and produce fertile
offspring
Produced when two closely related species reproduce. Hybrids are
not one species or the other but have characteristics of both. They
are usually infertile.
Neighbouring populations of the same species that have slightly
different characteristics but still interbreed to form a chain. The
two species at either end of the chain cannot interbreed.
The way an organisms is named using their Genus and species.
A change to help something carry out its job
Differences in characteristics
A measure of the total number of different species in an area
Discontinuous variation
Continuous variation
Hydrothermal vents
Normal distribution curve
Competition
Natural selection
Has a fixed set of values (no range). Data is represented as a bar
chart.
The values can be any number within a certain range (a scale).
Data is represented as a histogram or line graph.
Habitats deep in the sea which have high heat and pressure.
Often produced when we measure a characteristic with
continuous variation, most individuals fit in the middles section
with less at the extremes.
Where individuals compete for resources like food and space.
‘Survival of the fittest’ Individuals that survive can breed and
reproduce which means they pass their adaptations to the next
generation.
Evolution
A gradual change over time.
Extinct
When a species has died out.
Speciation
When a new species is formed
Chromosomes
Made of DNA and found in the nucleus of cells
Bases
Make up DNA, there are 4 bases A, T, C and G
Gene
A section of DNA
Mutation
Allele
A change in the genetic code (DNA)
Different form of a gene
Phenotype
A characteristic that you have i.e. blue eyes
Genotype
The pair of alleles that you have
Homozygous
A pair of the same alleles (aa or AA)
Gametes
The sex cells, egg and sperm.
Dominant
When the allele is present its characteristic will be expressed
Recessive
Two copies of the allele are required for the characteristic to be
expressed
Heterozygous
Carrier
Punnett square
Sickle cell disease
Cystic fibrosis
When you have two different alleles (Aa)
Someone who carries an allele for a genetic disease but doesn’t
have the disease themselves
A genetic diagram used to work out the probability of an offspring
being produced by a genetic cross
A recessive genetic disorder which causes sickle shaped red blood
cells
A recessive disease where the lungs get clogged with a thick
mucus
Key term
What it means
Pedigree analysis
Doctors use pedigree charts to understand how a disorder is
inherited and the probability that a person may have inherited the
disorder from their parents
Homeostasis
Negative feedback
The reflex arc
Osmoregulation
Hormones
Keeping the body’s internal conditions constant or stable
A change to the body happens in one direction and mechanisms in
the body work to make it change in the opposite direction
A chain of nerves that brings about a reflex response
The control of water in your body
Chemical messengers that are used by the endocrine system
Endocrine glands
Release hormones
Thermoregulation
The control of body temperature
Hypothalamus
An area of the brain involved in thermoregulation
Erector muscles
In the dermis of the skin contract to make the hair stand upright.
Vasoconstriction
When blood vessels narrow
Vasodilation
When blood vessels widen
Sense organ
Detects changes in the environment
Stimulus
Receptor cells
A change in the environment that your body is sensitive to
Cells in the sense organ that detect a stimulus
Impulses
Electrical signals sent by the nervous system
Neurones
Nerve cells
Nerves
Neurotransmission
Bundles of neurones
The transmission of impulses along neurones
Dendrons
Receive impulses from receptor cells or other neurones
Dendrites
Branches at the end of dendrons
Axon
Involuntary response
Central Nervous System (CNS)
Voluntary response
Carries impulses from the cell body to the brain or other neurones
A response that you don’t have to think about
Brain and spinal cord
A response where you have to think about your action
Sensory neurone
Send impulses from receptors to the central nervous system
Motor neurone
Send impulses from the central nervous system to effectors
Relay neurone
Short neurones in the spinal cord that link motor and sensory
neurones
Synapse
Neurotransmitter
Myelin sheath
Response
Effector
Reflex
Target organ
Insulin
Glucagon
Tiny gap that separates two neurones
Chemical substances used to transmit impulses through the gap
between neurones
A fatty layer surrounding the axon to insulate it and make
messages travel faster
What your body does in response to the stimulus
The muscle or organ that carries out the action
Automatic responses that are extremely quick and protect the
body.
An organ that responds to a certain hormone
A hormone produced by the pancreas to decrease the level of
blood glucose
A hormone produced by the pancreas to increase the level of
blood glucose
Glycogen
A store of glucose
Diabetes
A disorder where people cannot control their blood glucose very
well.
Subcutaneous fat
The fat layer beneath the skin where insulin is injected
Type 1 diabetes
Where the pancreas does not produce insulin
Type 2 diabetes
Cells in the body respond less well to insulin
Body Mass Index (BMI)
Tropism
Phototropism
Negative tropism
Auxin
Gravitropism/Geotropism
How healthy a person’s mass is for their height
Responding to a stimulus by growing towards or away from it
A tropism caused by light
A tropism away from a stimulus
A plant hormone that causes positive phototropism
Growth towards the direction of gravity
Germinates
Roots and shoots start to grow from a seed
Gibberellins
A plant hormone that stimulates flower and fruit production
Key term
Selective weedkiller
Rooting powders
Narcotic
Hallucinogen
What it means
Contains auxin. Makes plants with broad leaves grow out of
control and die.
Contains auxins. Makes roots develop quickly.
Drug that makes us feel sleepy
Change the way the brain works causing hallucinations
Stimulant
Speeds up neurotransmission so speeds up reaction times
Depressants
Slow down the activity of neurones in the brain so we relax
Addictive
Carcinogen
Tar
People become dependent on the drug
Chemical that causes cancer
Found in cigarettes, contains carcinogens
Carbon monoxide
Reduces the amount of oxygen that red blood cells can carry
Nicotine
The addictive part of tobacco that makes it difficult to give up
Cirrhosis
Liver disease where the normal tissue is destroyed
Physical barriers
Chemical defences
Stop pathogens entering the body
Kill pathogens before they can harm us
Antiseptics
Chemical substances that kill microorganisms outside the body
Antibiotics
Kill or prevent the growth of bacteria and some fungi but not
human cells
MRSA
Interdependent
Biomass
A bacterium resistant to many antibiotics
Organisms depend on each other
The mass of living things
Parasitism
Feeding relationship where only one organism benefits
Mutualism
Feeding relationship where both organisms benefit
Nitrogen fixing bacteria
Turn nitrogen in the air into nitrogen compounds
Chemosynthetic bacteria
Get their energy from chemical substances rather than light
Eutrophication
Where fertiliser increases the concentration of nitrates and
phosphates in water