B1 - GCSE

?
Topic 1
Key Concepts in Biology
1 of 352
All living things are made of...
...cells.
2 of 352
Cells can either be...
...eukaryotic or prokaryotic.
3 of 352
A prokaryote is...
...a prokaryotic cell.
4 of 352
What is a prokaryotic cell?
A single-celled organism.
5 of 352
What are subcellular structures?
The different parts of a cell.
6 of 352
Most cells are -(1)- for a particular function.
1:-specialised-
7 of 352
--(1)-- contain lots of different types of cells (ie cells with different -(2)- ).
1:- Multicellular organisms-; 2:-structures-
8 of 352
What are specialised cells?
Cells that have a structure which makes them adapted to their function.
9 of 352
Egg cells and sperm cells are specialised for...
...reproduction.
10 of 352
In sexual reproduction, the -(1)- of an egg cell -(2)- with the nucleus of a --(3)-- to create a --(4)--, which then develops into an -(5)-.
1:-nucleus-; 2:-fuses-; 3:-sperm cell-; 4:-fertilised egg-; 5:-embryo-
11 of 352
Why is it important that both the nucleus of an egg cell and of a sperm cell only contain half the number of chromosomes that's in a normal body cell?
It is important as it means that when an egg and sperm nucleus fuse at fertilisation the resulting cell will have the right number of chromosmes.
12 of 352
What is the function of sperm cells?
The function of a sperm is to transport the male's DNA to the female's egg.
13 of 352
What is magnifictaion?
Magnification is how many times bigger the image is.
14 of 352
--(1)-- are what makes you work. And -(2)- are what makes them work.
1:-chemical reactions-; 2:-enzymes-
15 of 352
What is the substrate?
The substrate is the molecule changed in the reaction.
16 of 352
Every enzyme has an...
...active site.
17 of 352
What is the active site?
The part where the enzyme joins on to its substrate to catalyse the reaction.
18 of 352
Enzymes usually only work with one substrate and are said to have...
...a high specifity for their substrate.
19 of 352
It's easy to detect starch using...
...iodine solution.
20 of 352
Explain the relationship/test of starch with iodine solution.
If starch is present, the iodine solution will change from browny-orange to blue-black.
21 of 352
Enzymes break down big molecules. Give some examples of said big molecules.
Proteins, lipids and some carbohydrates are big molecules.
22 of 352
What are lipids?
Lipids are fats and oils.
23 of 352
Why is it important that organisms break down big molecules?
It's important that organisms are able to break down big molecules into their smaller components so they can be used for growth and other life processes.
24 of 352
Enzymes called carbohydrases...
...convert carbohydrates into simple sugars.
25 of 352
What do proteases do?
Proteases convert proteins into amino acids.
26 of 352
What do lipases do?
Lipases convert lipids into glycercol and fatty acids.
27 of 352
What is amylase an example of and what does it do?
Amylase is an example of a carbohydrase. It breaks down starch into maltose and other sugars.
28 of 352
What happens when lipids are broken down?
When lipids are broken down, the fatty acids will lower the pH of the solution they are in.
29 of 352
Some enzymes join molecules together. Glycogen synthase is an enzyme that --(1)-- lots of chains of -(2)- molecules to make -(3)- .
1:-joins together-; 2:-glucose-; 3:-glycogen-.
30 of 352
What is glycogen?
Glycogen is a molecule used to store energy in animals.
31 of 352
What are biological molecules?
Molecules found in living organisms.
32 of 352
State three biological molecules.
Carbohydrates, proteins and lipids are all biological molecules.
33 of 352
How do you test for starch?
Starch is tested for using iodine?
34 of 352
How do you test for proteins?
The Biuret Test is used for proteins.
35 of 352
How do you test for sugars?
You can test for sugars using Benedict's Reagent.
36 of 352
How do you test for lipids?
Use the Emulsion Test for lipids.
37 of 352
Food can be -(1)- to see how much -(2)- it contains.
1:-burnt-; 2:-energy-
38 of 352
What is the scientific name for burning food to find out the energy content.
Calorimetry.
39 of 352
In calorimetry, quite a bit of the energy in the food is ----(1)----. You can minimise this by ...
1:-transferred to thge environment-; ...insulating the boiling tube e.g. with foil.
40 of 352
1cm cubed of water is the same as...
...1g of water.
41 of 352
Substances can move in and out of cells by...
diffusion, osmosis, and active transport.
42 of 352
Diffusion happens in both...
...liquids and agses.
43 of 352
Why can diffusion happen in these substances (gases and liquids)?
Diffusion happens in both liquids and gases because the particles in these substances are free to move about (randomly).
44 of 352
Only very -(1)- molecules can -(2)- through --(3)--.
1:-small-; 2:-diffuse-; 3:-cell membranes-.
45 of 352
Name 4 molecules that can diffuse through cell membranes .
Glucose, amino acids, water and oxygen.
46 of 352
Big molecules like -(1)- and -(2)- can't fit through the membranes.
1:-starch-; 2:-proteins-
47 of 352
Osmosis is a special case of...
...diffusion.
48 of 352
What is a partially permeable membrane?
A partially permeable membrane is one with very small holes in it that only tiny molecules e.g. water can pass through them, and bigger molecules (e.g. sucrose) can't.
49 of 352
In osmosis, high water concentration is...
...also low solute concentratiion.
50 of 352
in osmosis, low water concentration is...
... also high solute concentration.
51 of 352
Active transport works...
...against a concentration gradient.
52 of 352
Topic 2
Cells and Control
53 of 352
Explain why cells have to be able to divide.
In order to survive and grow, cells have got to be able to divide.
54 of 352
Chromosomes contain...
...genetic information.
55 of 352
Most cells in your body have...
...a nucleus.
56 of 352
The nucleus contains...
...your gentic material in the form of chromosomes.
57 of 352
What are chromosomes?
Chromosomes are coiled up length of DNA molecules.
58 of 352
--(1)-- normally have --(2)-- of each chromosome making them diploid cells.
1:-body cells-; 2:-two copies-
59 of 352
One chromosome come from the organism's -(1)- and one comes from its -(2)-.
1:-'mother'-; 2:-'father'-
60 of 352
Body cells in -(1)- organisms divide to produce new cells during a process called the --(2)--.
1:-multicellular-; 2:-cell cycle-
61 of 352
What is mitosis?
The stage of the cell cycle when the cell divides is called mitosis.
62 of 352
Multicellular organisms usew mitosis to...
...grow or to replace old and damaged cells.
63 of 352
Some organisms use mitosis to -(1)-, this is called --(2)--.
1:-reproduce-; 2:-asexual reproduction-
64 of 352
Growth involves...
...cell division, differentiation, and elongation.
65 of 352
What is growth?
Growth is an increase in size or mass.
66 of 352
Plants and animals grow and develop due to these processes...
...cell differentiation and cell division.
67 of 352
Plants also grow by...
...elongation.
68 of 352
What is a mutation?
A random change in a gene.
69 of 352
Percentile charts are used...
...to monitor growth.
70 of 352
What are growth charts for?
Growth charts are used to assess a child's growth over time, so that an overall pattern in development can be seen and any problems highlighted.
71 of 352
Name possible problems that can be highlighted using a growth chart.
Obesity, malnutrition, dwarfism.
72 of 352
A baby's growth is regularly monitored after birth to make sure it's growing normally. Three measurements are taken, what are they?
Length, mass and head circumference.
73 of 352
Name a process that's for growth in plants but not in animals.
Cell elongation.
74 of 352
Describe how a plant grows by cell elongation.
Cell elongation makes a plant's cells expand so the cells get biggerand the plant grows.
75 of 352
What are stem cells?
Stem cells are undifferentiated cells.
76 of 352
What can stem cells do?
Stem cells can differentaite into different types of cells.
77 of 352
What makes up the CNS (Central Nervous System)?
The brain and the spinal cord make up the CNS.
78 of 352
What is the spinal cord?
The spinal cord is a long column of neurones that run from the base of the brain down the spine.
79 of 352
What are neurones?
Neurones are nerve cells.
80 of 352
The brain is made up of...
...billions of interconnected neurones.
81 of 352
Explain the function of scanners.
The brain can be visualised without surgery using scanners; scanners are used to investigate brain functions. Scanners reduce the need for rsiky surgeries.
82 of 352
What is the nervous system?
The nervous system is what lets you react to what goes on around you.
83 of 352
The nervous system is made up of -(1)- which go to --(2)-- of the body.
1:-neurones-; 2:-all parts-
84 of 352
The body has lots of sensory receptors. What are sensory receptors?
Groups of cells that can detect a change in the environment.
85 of 352
Different receptors detect different stimuli. What do receptors in your eyes detect?
Receptors in the eyes detect light.
86 of 352
What do receptors in your skin detect?
Receptors in the skin detect touch(pressure) and temperature change.
87 of 352
What is a stimulus?
A stimulus is a chnage in the environment.
88 of 352
What is reaction time?
The time it takes you to respond to a stimulus.
89 of 352
What is a synapse?
The connection/gap between two neurones is called a synapse.
90 of 352
What are neurotransmitters?
Neurotransmitters are chemicals that transfer nerve siganls.
91 of 352
How do neurotransmitters move/travel?
They diffuse across the gap.
92 of 352
What is a reflex?
An automatic, rapid respsonse to stimuli.
93 of 352
What is the aim/purpose of a reflex?
To reduce the chances of being injured.
94 of 352
What is a reflex arc?
The passage of information in reflex (from receptor to effector) is called a reflex arc.
95 of 352
The neurones in reflex arcs go...
...through the spinal cord or (through) an unconscious part of the brain.
96 of 352
Why are reflexes quicker?
Because you don't have to spend time thinking about the response, it's quicker than normal responses.
97 of 352
---(1)--- can damage the eye so you have a reflex to --(2)--.
1:-Very bright light-; 2:-protect it-
98 of 352
The -(1)- is sensitive to -(2)- and responsible for sight.
1:-eye-; 2:-light-
99 of 352
The -(1)- from light is converted into --(2)--.
1:-information-; 2:-electrical impulses
100 of 352
The lens is -(1)-, so the eye can focus light onto the retina by ---(2)--- of the lens.
1:-elastic-; 2:-changing the shape-
101 of 352
Long and short-sightedness are caused by..
...structural abnormalities.
102 of 352
Long-sighted people are unable to...
...focus n near objects.
103 of 352
Short-sighted people are unable to...
...focus on distant object.
104 of 352
How can you correct long-sightedness?
You can use glasses or contact lenses with a convex lens.
105 of 352
How can you correct short-sightedness?
You can use glasses or contact lenses with a concave lens.
106 of 352
What is the most common form of colour blindness?
The most common form of the disorder is red-green colour blindness.
107 of 352
What is red-green colour blindness caused by?
It's caused when red or green cones in the retina are not working properly.
108 of 352
Is there a cure for colour blindness and explain why.
There's no cure for colour blindness at the moment because the cone cells can't be replaced.
109 of 352
Explain what a cataract is?
A cataract is a cloudy patch on the lens, which stops light from being able to enter the eye normally.
110 of 352
People with cataract are likely to have...
...blurred vision, difficulty seeing in bright light and may also experience colours looking less vivid.
111 of 352
A cataract can be treated by...
...replacing the faulty lens with an artificial one.
112 of 352
Topic 3
Genetics
113 of 352
Sexual reproduction produces...
...genetically different cells.
114 of 352
What is sexual reproduction?
Sexual reproduction is where genetic information from two organisms (a father and a mother) is combined to produce offspring which are genetically different to either parent.
115 of 352
In sexual reproduction, the father and mother produce -(1)- and in animals these are -(2)- and --(3)--.
1:-gametes-; 2:-sperm-; 3:-egg cells-
116 of 352
What are gametes?
Gametes are reproductive cells.
117 of 352
Gametes contain...
...half the number of chromosomes of normal cells.
118 of 352
What is meant by the term "normal cells"?
Cells with the full number of chromosomes.
119 of 352
What is a zygote?
A fertilised egg.
120 of 352
How does a zygote develop into an embryo?
by undergoing cell division (by mitosis).
121 of 352
What is the diploid number for a human?
46 chromosomes.
122 of 352
What is the haploid number for a human?
23 chromsomes.
123 of 352
Gametes are produced by...
...mitosis.
124 of 352
Meiosis is a type of...
...cell division.
125 of 352
How is meiosis different to mitosis?
It's different to mitosis because it doesn't produce identical cells.
126 of 352
In humans, meiosis only happens...
...in the reproductive organs.
127 of 352
What are the reproductive organs in humans?
Ovaries and testies.
128 of 352
The haploid gamete of a plant species has 12 chromosomes. Two of these gametes fuse to make a zygote. How many chromosomes will there be in the zygote?
24 chromosomes.
129 of 352
How does meiosis introduce genetic variation?
When the cell divides, some of the chromosomes from the organism's father and mother go into each new cell. The mixing up of the chromosomes/genes creates genetic variation.
130 of 352
Humans can only reproduce...
...sexually.
131 of 352
Some organisms can reproduce by either...
...sexual or asexual reproduction.
132 of 352
Reproducing is very important to all organisms. why?
It's how they pass on their genes.
133 of 352
Explain what happens when cells divide asexually.
They divide by mitosis resulting in two diploid daughter cells, which are genetically identical to each other and to the parent cell.
134 of 352
Explain sexual reproduction
It involves meiosis and the production of different haploid gametes, which fuse to form a diploid cell at fertilisation.
135 of 352
What is reproduction all about?
Passing on your DNA to the next generation.
136 of 352
DNA is made up of...
...nucleotides.
137 of 352
DNA strands are -(1)- made up of lots of repeating units called -(2)-.
1:-polymers-; 2:-nucleotides-
138 of 352
Each nucleotide consists of...
...one sugar molecule, one phosphate molecule and one 'base'.
139 of 352
Explain the sugar and phosphate molecules in the nucleotides.
The sugar and phosphate molecules in the nucleotides form a 'backbone' to the DNA strands.
140 of 352
What joins to each sugar?
One of four different bases joins to each sugar.
141 of 352
What are the bases in DNA?
A (adenine), T (thymine), C (cytosine), G (guanine).
142 of 352
A DNA molecule has ----(1)---- in the shape of a --(2)--.
1:-two strands coiled together-; 2:-double helix-
143 of 352
Base A ---(1)--- with T, and (base) C ---(2)--- with G. This is called ---(3)---.
1:-always pairs up-; 2:-always pairs up-; 3:-complementary base pairing-
144 of 352
Complementary base pairs are joined together by...
...weak hydrogen bonds.
145 of 352
DNA is stored as -(1)- and contains -(2)-.
1:-chromosomes-; 2:-genes-
146 of 352
What are chromosomes?
Chromosomes are long, coiled up molecules of DNA.
147 of 352
Where are chromosomes found?
They're found in the nucleus of eukaryotic cells.
148 of 352
What is a gene?
A gene is a section of DNA on a chromosome that codes for a particular protein.
149 of 352
All of an organism's DNA makes up its...
...genome.
150 of 352
Why is it useful to use salt when extracting DNA from fruit cells?
The salt helps the DNA stick together.
151 of 352
Proteins are made by...
...reading the code in DNA.
152 of 352
DNA controls...
...protein synthesis in a cell.
153 of 352
What is protein synthesis?
The production of proteins.
154 of 352
Proteins are made up of...
...chains of molecules called amino acids.
155 of 352
Each different protein has its own particular...
...number and order of amino acids.
156 of 352
What is triplet?
A code based on base triplets.
157 of 352
DNA also contains...
...non-coding regions.
158 of 352
Many regions of DNA are --(1)-- meaning that they --(2)-- for any --(3)--.
1:-non-coding-; 2:-don't code- 3:-amino acids-
159 of 352
All of an organism's DNA, including the ---(1)--- makes up the organism's -(2)-.
1:-non-coding regions-; 2:-genome-
160 of 352
Genetic variants can arise by...
...mutations.
161 of 352
What is a mutation?
A mutation is a rare, random change to an organism's DNA base sequence that can be inherited.
162 of 352
If a mutation happens in a gene, it produces a...
...genetic variant.
163 of 352
What is a genetic variant?
A different version of the gene.
164 of 352
A genetic variant may cause the activity of an enzyme to...
...increase, decrease or stop altogether.
165 of 352
Genetic variants could end up changing...
...the phenotype of an organism.
166 of 352
Mutations can also happen in ---(1)--- of DNA.
1:-non-coding regions-
167 of 352
Explain how a gene can code for a particular protein.
The order of bases in a gene determines the order of amino acids in a protein. Each gene contains a different order of bases, which the gene can code for a particular protein.
168 of 352
Explain how a genetic variant can result in a protein with a very low level of activity.
A genetic variant could alter the sequence of amino acids coded for by a gene which could affect the shape of the protein, decreasing its activity.
169 of 352
Proteins are made in -(1)- stages.
1:-two-
170 of 352
What are the two stages of protein synthesis?
Transcription and translation.
171 of 352
Where are proteins made?
Proteins are made in the cell cytoplasm by subcellular structures called ribosomes.
172 of 352
What is mRNA?
Messenger RNA is a molecule.
173 of 352
Why is mRNA used in protein synthesis as against DNA?
Information for proteins come from DNA however DNA is found in the cell nucleus and is too large to move out so the molecule mRNA is used to get the information from the DNA to the ribosome in the nucleus.
174 of 352
mRNA uses -(1)- instead of -(2)- as a base.
1:-uracil-; 2:-thymine-
175 of 352
The base uracil still pairs with...
...adenine.
176 of 352
What is RNA polymerase?
RNA polymerase is the enzyme involved in joining together RNA nucleotides to make mRNA.
177 of 352
Once the -(1)- is bound to a ribosome, the -(2)- can be assembled. This stage is called -(3)-.
1:-mRNA-; 2:-protein-; 3:-translation-
178 of 352
What are codons?
Codons are base triplets in mRNA.
179 of 352
What is a polypeptide?
A protein.
180 of 352
Gregor Mendel was an --(1)-- who trained in mathematics and --(2)--.
1:-Austrian monk-; 2:-natural history-
181 of 352
On his garden plot at the monastery in the mid 19th century, Mendel noted how...
...characteristics in plants were passed on from one generation to the next.
182 of 352
The results of Mendel's research were published in -(1)- and eventually became the foundation of --(2)--.
1:-1866-; 2:-modern genetics-
183 of 352
What are "hereditary units"?
Genes.
184 of 352
Suggest why the importance of Mendel's work wasn't realised straight away.
Scientists of the time didn't have the background knowledge to properly understand Mendel's findings because they didn't know about genes, DNA and chromosomes.
185 of 352
You can use genetic diagrams to predict...
...how different characteristics will be inherited.
186 of 352
What are alleles?
Alleles are different versions of the same gene.
187 of 352
What genes you inherit control...
...what characteristics you develop.
188 of 352
You have -(1)- versions (alleles) of --(2)-- in your body, one on --(3)-- in a pair.
1:-two-; 2:-every gene-; 3:-each chromosome-
189 of 352
Define homozygous?
Having two alleles that are the same for a particular gene.
190 of 352
Define heterozygous?
Having two alleles that are different for a particular gene.
191 of 352
Some alleles are -(1)- and some are -(2)-.
1:-dominant-; 2:-recessive-
192 of 352
Dominant alleles are shown...
...with a capital letter.
193 of 352
Recessive alleles are shown...
...with a lower case letter.
194 of 352
If an organism has one dominant allele and one recessive allele for a gene,...
...then the dominant allele will determine what characteristic is present.
195 of 352
To display a dominant characteristic,...
....an organism can have either two dominant alleles for a particular gene or one dominant and one recessive allele for that gene.
196 of 352
For an organism to display a recessive characteristic,...
...both its alleles must be recessive.
197 of 352
Define genotype.
Your genotype is the combination of alleles you have.
198 of 352
Define phenotype.
Your phenotype is the characteristics you have.
199 of 352
What is monohybrid inheritance?
The inheritance of a single characteristic.
200 of 352
A genetic diagram can show how -(1)- is determined in humans.
1:-sex-
201 of 352
All eggs have one X chromosome but a sperm can have...
...either an X or Y chromosome.
202 of 352
Sex determination in humans depends...
...on whether the sperm that fertilises an egg carries an X or Y chromosome.
203 of 352
What is a family pedigree?
A family tree of genetic disorders.
204 of 352
Some genetic characteristics are...
...sex-linked.
205 of 352
A characteristic is sex-linked if...
...the allele that codes for it is located on a sex chromosome.
206 of 352
What are sex-linked disorders?
Disorders caused by faulty alleles located on sex chromosomes.
207 of 352
Colour blindness is a --(1)-- disorder.
1:-sex-linked-
208 of 352
Colour blindness is caused...
...by a faulty allele carried on the X chromosome.
209 of 352
Name another sex-linked disorder aside from colour blindness.
Haemophilia.
210 of 352
There are --(1)-- that determine blood group.
1:-multiple alleles-
211 of 352
Humans have -(1)- potential blood types and the gene for blood type in humans has ---(2)---.
1:-four-; 2:-three different alleles-
212 of 352
Organisms of the --(1)-- will usually look slightly different; these differences are called the -(2)- within a species.
1:-same species-; 2:-variation-
213 of 352
What are the two types of variation?
Genetic and environmental.
214 of 352
Genetic variation within a species is caused by...
...organisms having different alleles (versions of genes) which can lead to differences in phenotype.
215 of 352
Genetic variations can be caused by...
...new alleles rising through mutations.
216 of 352
--(1)-- also causes genetic variation since it results in alleles being -(2)- in lots of --(3)-- in offspring.
1:Sexual reproduction-; 2:-combined-; 3:-different ways-
217 of 352
Environmental variations in phenotype are also known as...
...acquired characteristics.
218 of 352
Why are environmental variations also known as acquired characteristics?
Because they're characteristics that organisms acquire during their lifetimes.
219 of 352
Most variation in phenotype is determined by...
...a mixture of genetic and environmental factors.
220 of 352
What are mutations?
Mutations are changes to the base sequence of DNA.
221 of 352
When mutations occur within a gene they result in...
...an allele, or a different version of the gene.
222 of 352
Most mutations don't have any effect so in other words they are...
...neutral.
223 of 352
Why does sexual reproduction in genetic variation in a population?
It results in new combinations of alleles in offspring.
224 of 352
With the Human Genome Project, the big idea was...
...to find every single human gene.
225 of 352
State the start, end and results of the Human Genome Project.
The project officially started in 1990 and a complete map of the human genome, including the locations of around 20,500 genes, was completed in 2003.
226 of 352
The Human Genome Project has helped to identify about --(1)-- related to disease, which has huge potential -(2)- for -(3)-.
1:-1800 genes-; 2:-benefits-; 3:-medicine-
227 of 352
How could information from the Human Genome Project be used to help prevent individuals from developing certain diseases?
A person's genes can be used to help predict what diseases they're most at risk of devolving. This means that they could be given lifestyle and diet advice to help prevent them from getting the diseases.
228 of 352
Topic 4
Natural Selection and Genetic Modification.
229 of 352
What is evolution?
Evolution is the slow and continuous change from one generation to the next.
230 of 352
Charles Darwin came up with the theory of --(1)-- to explain how -(2)- occurs.
1:-natural selection-; 2:-evolution-
231 of 352
Natural selection means...
..."survival of the fittest".
232 of 352
Individuals in a population show --(1)-- because of differences in their -(2)-. New alleles arise through -(3)-.
1:-genetic variation-; 2:alleles-; 3:mutations-
233 of 352
State the three selection pressures.
Predation, competition for resources (e.g. food, water, mates, etc) and disease.
234 of 352
A species that can't compete is likely to go...
...extinct.
235 of 352
What is an antibiotic?
A drug designed to kill bacteria or prevent them from reproducing.
236 of 352
Why is it easy to see evolution in bacteria?
Because they reproduce so quickly.
237 of 352
What is a fossil?
A fossil is any trace of an animal or plant that lived a long time ago (e.g. over a thousand years).
238 of 352
Fossils are most commonly found in...
...rocks.
239 of 352
Generally, the -(1)- the rock the -(2)- the fossil.
1:-deeper-; 2:-older-
240 of 352
By arranging fossils in chronological order, what can be observed?
Gradual changes in organisms can be observed and this provides evidence for evolution, because it shows how species have changed and developed over billions of years.
241 of 352
How do fossils provide evidence that organisms evolved from simpler life forms?
Arranging fossils in chronological order shows gradual changes/development in organisms.
242 of 352
Describe Wallace's role in developing the theory of evolution by natural selection.
Wallace provided evidence for natural selection and worked with Darwin to develop the theory.
243 of 352
Evidence from -(1)- suggests that humans and -(2)- evolved from a --(3)-- that existed around --(4)-- years ago.
1:-fossils-; 2:-chimpanzees-; 3:-common ancestor-; 4:-6 million-
244 of 352
Human beings and their ancestors are known as...
...hominids.
245 of 352
Fossils of several --(1)-- have been found; these fossils have characteristics that are -(2)- apes and humans. By looking t --(3)-- you can see how much humans have -(4)- over time.
1:-hominid species-; 2:-between-; 3:hominid fossils-; 4:evolves-
246 of 352
-(1)- is a fossils hominid 4.4 million years old.
1:-'Ardi'-
247 of 352
-(1)- is a fossil hominid 3.2 million years old.
1:-'Lucy'-
248 of 352
--(1)-- is a fossil hominid 1.6 million years old.
1:-Turkana Boy-
249 of 352
Development of --(1)-- provides evidence for human evolution.
1:-stone tools-
250 of 352
What is a pentadactyl limb?
A pentadactyl limb is a limb with five digits.
251 of 352
You can see the pentadactyl limb in many species, e.g....
...mammals, reptiles, amphibians.
252 of 352
What is classification?
Classification is organising living organisms into groups.
253 of 352
Traditionally, organisms were classified according to...
...similarities and differences in their observable characteristics. As technology improved this included things you can see with a microscope, e.g cell structure.
254 of 352
What are the five kingdoms?
Animals, plants, fungi, prokaryotes, protists.
255 of 352
What are Woese's three domains?
Archaea, Bacteria, Eukarya.
256 of 352
Give one example of how advances in technology allowed scientists to distinguish between Archaea and Bacteria.
RNA/DNA sequencing showed that Archaea and Bacteria were less closely related than first thought.
257 of 352
Give the simple definition of selective breeding.
Taking thee best best plants or animals and breeding them together to get the best possible offspring.
258 of 352
Give the scientific definition of selective breeding.
When humans artificially select the plants or animals that are going to breed so that the genes for particular characteristics remain in the population.
259 of 352
Organisms are --(1)-- to develop features that are -(2)- or -(3)-.
1:-selectively bred-; 2:-useful-; 3:-attractive-
260 of 352
Tissue culture involves...
...taking little bits tissues and growing them on an artificial growth medium.
261 of 352
The plants produced via tissue culture are -(1)- and are --(2)-- organisms.
1:-clones-; 2:-genetically identical-
262 of 352
You can use tissue culture to create lines of clones all with the same beneficial features e.g. ...
...pesticide resistance, tasty fruit, etc.
263 of 352
Genetic engineering involves...
...modifying an organism's genome (it's DNA)to introduce desirable characteristics.
264 of 352
Genetic engineering involves the use of...
...enzymes and vectors (carriers).
265 of 352
What are recombinant DNA?
Two different bits of DNA stuck together.
266 of 352
What is a vector?
A vector is something that's used to transfer DNA into a cell and can be used to insert DNA into other organisms.
267 of 352
There are two sorts of vectors, what are they?
Plasmids and viruses.
268 of 352
Genetic engineering is useful in -(1)- and -(2)-.
1:-agriculture-; 2:-medicine-
269 of 352
Explain one benefit of being able to genetically engineer herbicide-resistant crops.
It can improve the yield of the crop because herbicide-resistant crops can be sprayed with herbicides to kill weeds without the crop being damaged.
270 of 352
Describe restriction enzymes.
Restriction enzymes recognise specific sequences of DNA and cut the DNA at these points; the pieces of DNA are left with sticky ends where they have been cut.
271 of 352
Describe ligase enzymes.
Ligase enzymes are used to join two pieces of DNA together at their sticky ends.
272 of 352
What does GMO stand for?
Genetically modified organisms.
273 of 352
Suggest three methods that could be used to help provide food for a growing human population.
Use of GM crops with improved yields; use of fertilisers on poor soils; use of biological pest control methods.
274 of 352
What is WHO?
The World Health Organisation.
275 of 352
What is the WHO's definition of health?
A state of complete physical, mental, and social well-being, and not merely the absence of disease or infirmity.
276 of 352
Infirmity means...
...weakness or frailness, commonly due to old age.
277 of 352
What is disease?
A disease is a condition where part of an organism doesn't function properly.
278 of 352
There are two sorts of disease. What are they?
Communicable and non-communicable.
279 of 352
Describe communicable diseases?
Communicable diseases are diseases that can be spread between individuals.
280 of 352
Describe non-communicable diseases?
Non-communicable diseases can't be transmitted between individuals e.g. cancer and heart disease.
281 of 352
If you are affected by one disease, it could make you...
...more susceptible to others as your body may become weakened by the disease, leaving it less able to fight off others.
282 of 352
Being susceptible to a disease, means...
...that you have an increased chance of getting it.
283 of 352
What are pathogens?
Pathogens are organisms that cause communicable diseases and include viruses, bacteria, fungi and protists.
284 of 352
What pathogen causes cholera and tuberculosis?
A bacterium.
285 of 352
What pathogen causes malaria?
A protist.
286 of 352
What pathogen causes stomach ulcers?
A bacterium.
287 of 352
What pathogen causes chalara ash dieback?
A fungus that infects ash trees.
288 of 352
What pathogen causes ebola?
A virus.
289 of 352
How does cholera spread?
Via contaminated water.
290 of 352
How does tuberculosis spread?
Through the air when infected individuals cough.
291 of 352
How do stomach ulcers spread?
Oral transmission (e.g. swallowing contaminated water or food).
292 of 352
How does ebola spread?
Via bodily fluids.
293 of 352
How does chalara die ashback spread?
It's carried through the air by the wind. It also spreads when diseased ash trees are moved between areas.
294 of 352
How does malaria spread?
Mosquitoes act as animal vectors (carriers), passing on the protist to humans but not getting the disease themselves.
295 of 352
Viruses can only reproduce...
...inside living cells.
296 of 352
Viruses aren't cells; they're usually no more than a --(1)-- around a strand of --(2)--.
1:-protein coat-; 2:-genetic material-
297 of 352
Viruses have to ---(1)--- (called host cells) in order to reproduce.
1:-infect living cells-
298 of 352
The --(1)-- of a virus starts with when it infects a new --(2)--.
1:-life cycle-; 2:-host cell-
299 of 352
What are the two forms of reproduction for viruses.
The lytic pathway and the lysogenic pathway.
300 of 352
What is the most common form of reproduction for viruses?
The lytic pathway.
301 of 352
STIs are infections that are spread through...
...sexual contact, including sexual intercourse.
302 of 352
Plants produce chemicals called -(1)- which kill bacterial and fungal -(2
1:-antiseptics-; 2:-pathogens-
303 of 352
Plants also produce -(1)- to deter -(2)- from -(3)- on their leaves.
1:-chemicals-; 2:-pests-; 3:-feeding-
304 of 352
Plant diseases can be -(1)- in the -(2)- and in the -(3)-.
1:-detected-; 2:-field-; 3:-lab-
305 of 352
In the field, plant diseases are usually detected...
...by observations.
306 of 352
What are plant pathologists?
Experts in plant disease.
307 of 352
What are galls?
Abnormal growths.
308 of 352
With plants, what might galls indicate?
Galls (abnormal growth) might indicate crown gall disease.
309 of 352
Different pathogens are spread in different ways, e.g. patches of diseased plants may suggest...
...that the disease is spread through the soil.
310 of 352
Different pathigens are spread in different ways, e.g. a random distribution of diseased plants may suggest...
...an airborne pathogen.
311 of 352
Laboratory-based --(1)-- allows accurate -(2)- of specific pathogens.
1:-diagnostic testing-; 2:-identification-
312 of 352
Laboratory-based diagnostic testing might involve --(1)-- or --(2)--.
1:-detecting antigens-; 2:-detecting DNA-
313 of 352
Like plants, the human body has -(1)- and -(2)- defences against pathogens.
1:-physical-; 2:-chemical-
314 of 352
These physical and chemical barriers are...
...non-specific and they work against many different types of pathogens.
315 of 352
If pathogens do make it into your body, your --(1)-- kicks in to -(2)- them.
1:-immune system-; 2:-destroy-
316 of 352
The most important part of your immune system is...
...the white blood cells.
317 of 352
B-lymphocytes are a type of white blood cell that are involved in...
...the specific immune response.
318 of 352
Memory lymphocytes give -(1)- to late infection.
1:-immunity-
319 of 352
Immunisation stops you...
...getting infections.
320 of 352
What are epidemics?
Big outbreaks of diseases.
321 of 352
What are B-lymphocytes?
A type of white blood cell that is involved in the specific immune response and produces antibodies.
322 of 352
Why is the secondary immune response to a pathogen much faster than the first respsonse?.
Memory lymphocytes are produced in response to a foreign antigen and remain in the body for a long time. So when the pathogen enters the body again, there are more cells that recognise it and can produce antibodies against it.
323 of 352
Antibodies are produced by...
...B-lymphocytes, a type of white blood cell.
324 of 352
Briefly explain pregnancy tests.
A hormone (HCG) is found in the urine of women only when they are pregnant, pregnancy testing sticks detect this hormone.
325 of 352
What is a hybridoma cell made from?
A (mouse) B-lymphocytes and a tumour (myeloma) cell called a myeloma cell.
326 of 352
What are tumour markers?
Proteins found on the cell membrane of cancer cells.
327 of 352
Why is antibody-based anti-cancer drug superior to other drugs or radiotherapy?
Other cancer treatments (e.g. radiotherapy) can affect normal body cells as well as killing cancer cells so the side effects of an antibody-based drug are lower than for other drugs or radiotherapy, thus making them superior.
328 of 352
Antibiotics are used to treat...
...bacterial infections.
329 of 352
How do antiobiotics work?
Antiobiotics work by inhibiting processes in bacterial cells, but not in the host organism.
330 of 352
Some antibiotics inhibit the building of bacterial cells, explain what this does.
This prevents the bacteria from dividing, and eventually kills them, but has no effect on cells in the human host (which don't have cell walls).
331 of 352
Different antibiotics kill different types of bacteria, so it's important...
...to be treated with the right one.
332 of 352
Antibiotics don't destroy viruses. Why?
Viruses reproduce using the host's body cells, which makes it very difficult to develop drugs that destroy just the virus without killimg the body's cells.
333 of 352
State the difference between antibiotics and antiseptics.
Antiobiotics kill bacteria inside the body; antiseptcis kill bacteria outside the body (e.g. on the skin).
334 of 352
What is an inhibition zone?
A clear area left where bacteria have died.
335 of 352
The more effective the antibiotic is against the bacteria,...
...the larger the inhibition zone.
336 of 352
Smoking is a major risk factor associated with...
...cardiovascular disease.
337 of 352
What is cardiovascular disease?
Any disease associated with the heart or blood vessels e.g. a heart attack or stroke.
338 of 352
a diet with too many or too few nutrients...
...can lead to malnutrition and diseases associated with malnutrition, e.g. scurvy.
339 of 352
What is scurvy?
A vitamin C deficiency disease.
340 of 352
Getting too many nutrients is also a form of -(1)-, and can lead to -(2)-.
1:-malnutrition-; 2:-obesity-
341 of 352
What are risk factors for obesity?
Not getting enough exercise and having a diet high in fat and sugars.
342 of 352
Drinking too much alcohol is a major risk factor for...
...the development of liver disease.
343 of 352
What is cirrhosis?
Scarring of the liver.
344 of 352
As well as smoking, there are lots of other risk factors associated with cardiovascular disease, including:...
...drinking too much alcohol, lack of exercise, and a diet high in saturated fat.
345 of 352
Many non-communicable diseases are caused by --(1)-- rsik factors -(2)- with each other, rather than ---(3)---, including cancer, liver and lung disease and obesity.
1:-several different-; 2:-interacting-; 3:-one factor alone-
346 of 352
Obesity is a risk factor for other non-communicable diseasess, e.g....
...type 2 diabetes and cardiovascular disease.
347 of 352
Give examples of lifestyle factors that increase the rsik of cardiovascular disease.
Smoking;diet high in saturated fat;drinking too much alcohol;not enough exercise;obesity.
348 of 352
The Body Mass Index (BMI) is used as a guide to help decide...
...whether someone is underweight, normal, overweight or obese.
349 of 352
Excess aenergy is stored as...
...fat.
350 of 352
BMI isn't always reliable measure of obesity. Give an example of why.
For example, athletes have lots of muscles, which weighs more than fat, so they can come out with a high BMI even though they're not overweight.
351 of 352
What does CVD stand for?
Cardiovascular disease.
352 of 352

Other cards in this set

Card 2

Front

All living things are made of...

Back

...cells.

Card 3

Front

Cells can either be...

Back

Preview of the front of card 3

Card 4

Front

A prokaryote is...

Back

Preview of the front of card 4

Card 5

Front

What is a prokaryotic cell?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all All resources »