Category: Biology

PCR allows DNA to replicate by semi-conservative replication. But what word best describes the rate at which it amplifies?

Usually the cut out gene is inserted into a vector. Which of the following is a vector for use in genetic modification of bacteria?

Can extra methylation be removed from the DNA?

What is 'Epigenetics'?

What substances can be used to take mature, differentiated adult cells, and de-differentiate them back into pluripotent stem cells ?(usually only found in embryos).

iPS cells can be made from adult somatic cells. What are somatic cells?

What does the RISC complex do to the mRNA?

What does the 'si' stand for in siRNA?

What is the oestrogen receptor called when the oestrogen has bound?

Oestrogen can act as a transcription factor. To do so, it needs to bind to what molecule?

What are the proteins called that also need to bind to activate RNA polymerase?

What is the removal of introns called?

What is the difference between mRNA and pre-mRNA?

Which molecule is created during transcription?

Which of the following describes the structure of DNA?

Fill in the missing word : Causes of Mutations A mutation is any change to the order of __12___ in the genetic code. These occur naturally as the enzyme _____13_____ replicates the DNA and makes mistakes. The incidence can also be produced due to exposure to certain agents called mutagenic agents.

These can be chemicals such as nitrous acid, which converts cytosine to uracil. Nitrous acid would therefore cause a __14___ mutation. Ethidium Bromide is used to stain DNA during gel electrophoresis. It can insert between bases, acting in a similar way to an addition mutation and therefore causing a __15___ along the rest of the gene. UV radiation is also a mutagenic agent.

It can cause bonds to form between pyrimidine bases ( thymine and cytosine). This bonding causes polymerases to misread or stop working all together at that point.

What is the position of gene on a chromosome called?

Which word describes the sequence of three bases on DNA that code for an amino acid?

Which of the following is not coded for by a gene?

What does the C stand for in the genetic code?

Which of the following does NOT stop succession?

What do we call a stage of succession?

Which stage represents lichen and mosses?

True or false : Succession involves only the change of biotic factors ( Not abiotic).

Is the following an 'Abiotic adaptation' or a 'Biotic Adaptation': Monarch butterflies fly south when the number of daylight hours shorten?

What is the word used to describe 'The specific role of a species within its habitat'?

What is the word used to describe 'Populations of different species in specific habitat'?

Speciation is when a new species arises from another: they can no longer produce fertile offspring because their DNA is no longer compatible. What term describes this inability between two populations to reproduce successfully?

What type of variation is show in the graph?

Which type of selection is when the number of individuals with a particular characteristic, increase around a middle or mid value, and outliers decrease?

Natural Selection is when organisms which are better adapted are more likely to survive and pass on their genes. Factors which affect the chance of survival are called selection pressures. These can be positive ( advantageous) or negative ( disadvantageous). Which of these is a negative selection pressure?

Tay Sachs is a recessive disease which leads to the build up of certain lipids which eventually become toxic. The Cajun community in the USA has an incidence of about 1 in every 3,500 births. What is the number of homozygous dominant healthy individuals in a Cajun population of 100,000 people?

What does 'p' represent ?

In hamsters two genes are autosomally linked : Fur and Eye colour . Where Ginger fur = G, and White fur =g. Black eyes = B and red eyes = b. In a cross between a homozygous recessive male for both traits and a heterozygous female for both traits , what would be the expected ratio of Ginger & Black eye, White and Black eye, ginger and red eye and white with red eyes?

Which type of allele tends to be sex linked?

How can you tell from a pedigree (family tree) that a trait is sex linked?

What is the definition of 'homozygous'?

What is a gene?

Which protein found in a myofilament has multiple globular heads? (Type your answer carefully).

The image above shows a muscle fibre. What is the function of organelle E?

When a stimulus is detected by a receptor, it generates a potential difference across it's plasma membrane. What is the name of this potential difference?

On the diagram, F is a voltage gated ion channel on an excitatory synapse, but which type of ion does it allow through?

Why does an increase in temperature ( up to 40 degrees) cause an increase in the speed of conduction along a neurone?

True or False - The speed of conduction along an unmyelinated neurone is around 5 m/s ( jogging pace).

Once an action potential has been generated, why is the wave of depolarisation only in one direction?

In the above diagram, which graph shows the correct effects of increasing a stimulus?

After an action potential has fired, the refractory period acts as the following:

• a) Prevents action potentials overlapping
• b) Limit the frequency of action potentials
• c) Limit the size of action potentials
• d) Makes action potentials travel unidirectionally.

True or False: A stronger stimulus will generate more frequent action potentials.

True or false: If more sodium channels are opened by a stimulus, then the action potential which is generated is bigger.

Which of the events (A - F above) starts depolarisation? Type the letter in the box

What ion is moving during process '3' on the above diagram?

When an neurone axon is at rest, what charge is the extra cellular fluid compared to the cytoplasm?

• a) Simple Diffusion
• b) Facilitated Diffusion
• c) Active Transport

What would be a suitable control for Went's experiment ?

What does Darwin's experiment where he placed a black cover over the tip show?

What does Darwin's experiment where he removed a shoot tip then replaced it show?

How does IAA become unevenly distributed?

In shoot tips which are lit from the side, where will the highest concentration of IAA be found?

How does IAA bring about this effect?

Denitrifying bacteria use nitrates in the soil to carry out respiration and produce nitrogen gas. Are the vast majority aerobic or anaerobic?

External digestion involves the secretion of enzymes outside of the organisms outer-most layer. Which term best describes this?

In the absence of oxygen as the final electron acceptor, some processes of aerobic respiration cannot occur. Some of the processes however can continue, which is the last stage that can still function?

Is the column for Krebs in the above diagram correct?

Is the column for the link reaction in the above diagram correct?

Using the ETC, how many molecules of ATP can each reduced FAD generate?

What is passed along the 4 protein complexes - represented by 'W' on the diagram?

How many molecules of reduced NAD ( or NADH) are generated in aerobic respiration from one molecule of glucose?

How many carbon atoms are in a single molecule of Oxaloacetate?

Which two processes turn Citrate into the 5C intermediate?

Name molecule X

Which graph represents the effect of changing the concentration of carbon dioxide on the rate of photosynthesis?

In the above experiment, chloroplasts were isolated from plants grown at different light intensities. In each trial scientists collected oxygen for 15 minutes. Calculate the difference in oxygen produced from mutant plants at low and high light intensities at a light intensity of 500 μmol photons m^–2s^–1. Measured in μmol O2 mg^–1 hour^–.

How many molecules of C are required to produce one molecule of glucose?

How many carbon atoms are there in ONE molecule of substance B?

Name substance A

Which two products from the Light Dependent Reactions ( LDRs) does the Calvin Cycle use?

What type of molecule is represented by 'C'?

The splitting of water at PSII creates molecules A & B, what do A and B represent?

Which membrane is represented by 'C' on the diagram?

PCR allows DNA to replicate by semi-conservative replication. But what word best describes the rate at which it amplifies?

Sometimes when trying to find a gene which important in a particular disease, it is useful to find out what genes the diseased cells have used (expressed) by extracting mRNA rather than DNA. However, mRNA cannot be used in genetic modifications. What do we need to change it into to be able to use it?

Where is the oestrogen receptor located?

Where are transcription factors often stored?

If hypomethylation ( reduced methylation) happens to a tumour suppressor gene what effect will this have on the rate of mitosis?

Name the type of reaction that joins the nucleotides together.

Which method would you use to see if there is a difference between the percentage cover of moss on the north face compared to the south face of tree trunks?

Which method would you use to see if there is a correlation between profile height and percentage cover of marsh grass?

Was the reduction in insects caused by the cold weather an abiotic factor or a biotic factor?

What type of population does genetic drift have the greatest effect on?

Speciation is when a new species arises from another: they can no longer produce fertile offspring because their DNA is no longer compatible. What term describes this inability between two populations to reproduce successfully?

In peppered moths, having light coloured wings is dominant. In Sheffield (an industrial northern town in the UK) a sample of moths was taken. The numbers collected were 73 light coloured , and 326 dark coloured. What proportion of all alleles are for the dark one?

In the actual ratio of 6:1:1:6, there were more of the ginger and black eyed hamsters and more of the white with red eyed hamsters than expected. Therefore, there are proportionately fewer of the mixed traits (Ginger and red eyes and white with black eyes). What process allowed those few mixed trait offspring to occur?

Marfan Syndrome ( TGF Beta) is dominant (T) to the healthy recessive allele(t) . Having a V shaped hairline (V) is dominant to having a straight hairline (v). What percentage of the offspring of a father = TtVv and a mother TtVv will have Marfan syndrome and a V shaped hair-line ?

One form of muscle disease is caused by a mutated allele of a gene. This leads to production of myosin molecules that are unable to bind to other myosin molecules. If myosin molecules are unable to bind to other myosin molecules, this prevents muscle contraction. Suggest why.

What reduces the concentration of neurotransmitter in a synapse after it has diffused across?

True or False : Fungi can increase the uptake of inorganic ions from the soil by a plant.

Which would be the most accurate method of sampling dry biomass?

In the above experiment, chloroplasts were isolated from plants grown at different light intensities. The mutant plants produced more chlorophyll b . The scientists predicted the mutant plants would grow better in any light intensity; why might this be?

Which two products from the Light Dependent Reactions ( LDRs) does the Calvin Cycle use?

Using bacteria is an example of what type of DNA Amplification?

What do we call enzymes that cut DNA at specific base sequences?

Which type of stem cells are not found in adults?

The mRNA travels to the ribosome, where it feeds between the two subunits, exposing the template bases. tRNA molecules each carry a specific amino acid at the top, with a complementary sequence of three bases called an anti-codon at the bottom. The tRNA anticodons then complementary base pair with the mRNA codon. In the ribosome there are 3 binding sites for tRNA, two where a peptide bond is formed between the carried amino acids.

These amino acids then form a ____10_____ chain which leaves the ribosome. The third site is a departure site, where the tRNA which has released its amino acid departs to pick up a new amino acid. Once the entire mRNA sequence has been ____11____, it can either pass into another ribosome to make another polypeptide or be degraded.

Which type of DNA is not circular?

Each complementary strand of DNA runs in opposite directions. What word describes this?

Name the method by which DNA replicates.

Name the type of bond that holds the complementary base pairs together.

What is lichen made out of ?

Which stage represents lichen and mosses?

What should you use to estimate a population of a sessile organism?

Marfan Syndrome ( TGF Beta) is dominant (T) to the healthy recessive allele(t) . Having a V shaped hairline (V) is dominant to having a straight hairline (v). What is the percentage probability of the offspring of a father = TtVv and a mother = TtVv would have Marfan Syndrome and a straight hair - line ?

Which of the above diagrams represents the myofilaments a 'Z line' in muscle?

The image above shows a muscle fibre. Name organelle A

Which ions are moving across the membrane during process '4'?

True or False : Fungi can increase the surface area of roots

What are the strands of fungi called?

Which stage of the nitrogen cycle does the above equation represent?

In the above experiment, chloroplasts were isolated from plants grown at different light intensities. In each trial scientists collected oxygen for 15 minutes. Calculate the difference in oxygen produced from mutant plants at low and high light intensities at a light intensity of 500 μmol photons m^–2s^–1. Measured in μmol O2 mg^–1 hour^–.

Name structure B

True or False : Symbiotic fungi generally increase the amount of glucose in a plant.

Nitrogen fixation from gas to compound, requires a large amount of energy (at least 16 ATP molecules and 8 electrons). A select few bacteria can carry out this task, but which of the following CANNOT fix nitrogen?

Which process can occur due to the actions of Nitrosomonas bacteria?

What is the formula for NPP?

Which would be the most accurate method of sampling dry biomass?

What would be the most appropriate units for measuring biomass?

The diagram above shows one form of anaerobic respiration, name molecule 'Z'.

Using the ETC, how many molecules of ATP can each reduced FAD generate?

What is represented by molecule Y?

How many molecules of reduced NAD ( or NADH) are generated in aerobic respiration from one molecule of glucose?

Molecule Z represents ATP. How is this molecule of ATP generated?

How many carbon atoms are in a single molecule of molecule B?

How many carbon atoms are carried into the Krebs cycle in each Acetyl Co A?

Name molecule X

Which graph represents the effect of changing the temperature on the rate of photosynthesis?

True or False - Using a different solvent does not alter the distance travelled by different substances in this technique?

Name substance C

Why can it be advantageous to a plant for more of process 'G' to occur?

In the chloroplast, many chlorophyll molecules (and other pigments) are attached to protein complexes in the internal membranes, labelled 'A' on the diagram. What are these complexes called ? ( Plural please!)

Name structure B

Breaks down ATP on myosin head

Which protein blocks the actin-myosin binding site in a relaxed myofibril?

Which of the above diagrams represents the myofilaments an 'M line' in muscle?

Point C is the point where most colour sensitive photoreceptor cells are located. What is it called?

When the layers of connective tissue are pressed, what happens to the neurone membrane?

GABA is a neurotransmitter released in some inhibitory synapses in the brain. GABA causes negatively charged chloride ions to enter postsynaptic neurones. Explain how this inhibits postsynaptic neurones

What term is used to describe when more than one presynaptic neurone releases its neurotransmitter onto single post-synaptic neurone? ( Type your answer carefully)

On the diagram, F is a voltage gated ion channel on an excitatory synapse, but which type of ion does it allow through?

True or False - Axons with a narrower diameter have a faster speed of conduction.

After an action potential has fired, the refractory period acts as the following:

• a) Prevents action potentials overlapping
• b) Limit the frequency of action potentials
• c) Limit the size of action potentials
• d) Makes action potentials travel unidirectionally.

Name stage 5 on the above diagram ( spell it carefully!)

What causes a change in the type of channels that are open at stage '4' ?

Name the process happening at '4' on the above diagram?

Which direction are the ions moving during process 3 on the above diagram?

Stimulation ( either by a generator potential in a receptor cell or a neurotransmitter binding to a receptor on a postsynaptic membrane) caused which type of channel to open?

Which word best describes the charge distribution across a resting axon plasma membrane?

Honey bees can detect the polarised light from the sun and use it to navigate even in cloudy weather. Is this taxis or kinesis?

True or False : Taxis is when an organism either moves faster in harsh conditions or turns less in harsh conditions.

What would be a suitable control for Went's experiment ?

What effect does low concentrations of IAA have on root tissue?

What is the native climax community in the UK?

Which type of plants are more likely to be the pioneer species in secondary succession?

Which of the following is an example of secondary succession?

Between stages B and C, what will happen to soil depth?

Which stage represents lichen and mosses?

What is the biological meaning of succession?

Which of the following is not an assumption that affects the accuracy of the Mark Release Recapture population estimate?

What is the advantage of carrying out an interrupted belt transect compared to belt transect?

Was the cold winter an example of an abiotic factor or a biotic one?

Is the following an 'Abiotic adaptation' or a 'Biotic Adaptation': Monarch butterflies fly south when the number of daylight hours shorten?

What type of population does genetic drift have the greatest effect on?

Natural Selection is when organisms which are better adapted are more likely to survive and pass on their genes. Factors which affect the chance of survival are called selection pressures. These can be positive ( advantageous) or negative ( disadvantageous). Which of these is a negative selection pressure?

In the creation of gametes, which process mixes up the alleles?

Tay Sachs is a recessive disease which leads to the build up of certain lipids which eventually become toxic. The Cajun community in the USA has an incidence of about 1 in every 3,500 births. What is the number of sufferers of Tay Sachs in a Cajun population of 100,000 people?

Tay Sachs is a recessive disease which leads to the build up of certain lipids which eventually become toxic. The Cajun community in the USA has an incidence of about 1 in every 3,500 births. What is the allele frequency of the normal healthy genes?

The probability of an individual having Cyctic Fibrosis is about 1 in 2500 in the UK. What proportion of the population will be carriers?

This gene interaction once again alters the phenotype ratio. Which type of Epistatic allele will produce a ratio of 9:3:4?

In Guinea pigs, ginger(G) hair is dominant to white(g), and short hair (S) is dominant to long (s). In the following cross: GgSs and GgSS, what percentage chance will the offspring being born short haired and white?

How can you tell when an allele is recessive in a pedigree (a family tree)?

Sometimes, two marker genes are used: The first marker gene is often an antibiotic resistance gene to show if the plasmid is present; the bacteria can only grow on a plate containing the antibiotic, if they have the antibiotic resistance gene on the plasmid. The second is often a gene with a colour change, which is broken by the insertion of the fragment.

e.g. An example of a gene to test for the presence of a fragment is Green Fluorescent Protein (GFP) glowing or not. What would a bacterial plate look like that contained an antibiotic, and was spread with bacteria which had been transformed with a plasmid and had a new gene fragment in?

What bond does DNA ligase create?

What is the active site of a restriction endonuclease complementary too?

What are iPS cells?

The morula hollows out into a hollow sphere, with a small group of cells at the bottom called teh inner cell mass which go on to develop into an embryo. What do the outer cells go on to make?

In humans, the zygote ( fertilised egg ) divides into a ball of cells called a Morula. What word describes the cells contained in a morula?

Which enzyme will the Oestrogen - Oestrogen Receptor ( OOR) activate?

What is the oestrogen receptor called when the oestrogen has bound?

Where is the oestrogen receptor located?

Where are transcription factors often stored?

The mRNA travels to the ribosome, where it feeds between the two subunits, exposing the template bases. tRNA molecules each carry a specific ______6____at the top, with a complementary sequence of three bases called an _____7_____ at the bottom. The tRNA anticodons then complementary base pair with the mRNA ____8____.

In the ribosome there are 3 binding sites for tRNA, two where a ____9____ bond is formed between the carried amino acids. These amino acids then form a ____10_____ chain which leaves the ribosome.

The third site is a departure site, where the tRNA which has released its amino acid departs to pick up a new amino acid. Once the entire mRNA sequence has been ____11____, it can either pass into another ribosome to make another polypeptide or be degraded.

What is the removal of introns called?

Which molecule is created during transcription?

Which enzyme is used during transcription?

If a tumour suppressor gene mutates, then it can mean the protein it codes for is non-functional. What will happen to the rate of mitosis if this happens?

Cancer is often caused by a mutation causing a cell to divide uncontrollably and spread into other tissues. Name the gene that normally increases cell division:

Fill in the missing word : Causes of Mutations A mutation is any change to the order of __12___ in the genetic code. These occur naturally as the enzyme _____13_____ replicates the DNA and makes mistakes. The incidence can also be produced due to exposure to certain agents called mutagenic agents. These can be chemicals such as nitrous acid, which converts cytosine to uracil.

Nitrous acid would therefore cause a __14___ mutation. Ethidium Bromide is used to stain DNA during gel electrophoresis. It can insert between bases, acting in a similar way to an addition mutation and therefore causing a __15___ along the rest of the gene. UV radiation is also a mutagenic agent.

It can cause bonds to form between pyrimidine bases ( thymine and cytosine). This bonding causes polymerases to misread or stop working all together at that point.

TTA = Leu TTG = Leu TTC = Phe TCA = Ser TAA = Stop Here is the original sequence : TTCTTGTTATCATAA. Here is a mutated sequence: TTCTTGTTATAACATAA.

What will be the effect on the mutated polypeptide?

TTA = Leu TTG = Leu TTC = Phe TCA = Ser TAA = Stop Here is the original sequence : TTCTTGTTATCATAA. Here is a mutated sequence: TTCTTATTATCATAA.

Will this mutation affect the primary structure of the polypeptide ?

What attracts new 'free' nucleotides to the exposed template strand during DNA replication?

Which of the following is a mutagenic agent?

In eukaryotes, the pre-mRNA is modified by removing what?

Which word does NOT describe the genetic code?

Which of the following is not coded for by a gene?

Which direction will the bubble move?

Which of the following would decrease the rate of transpiration?

Why can we not state using this data, CVD is caused by smoking?

How many oxygen molecules can each haem group carry?

Which of the following is a similarity between diffusion an osmosis?

In the above diagram of three cells, will water move from :

Which of the following molecules can diffuse directly through the phospholipid bilayer?

a) Oxygen
b) Carbon Dioxide
c) Lipids

Which organelle will be found in pellet B?

The Christae of the mitochondrion shown in this picture are 2m x 10^-8wide (A). How many 'nm' is this ?

Name structure A

Name this organelle.

Name the pentose sugar found in DNA.

Describe what the line would look like when a non-competitive inhibitor was added to the reaction.

Which points on the above graph show when the enzyme is denatured?

Starch is insoluble. What is that advantage of being insoluble?

What type of bond forms between two monosaccharides?

Many important substances in biological systems are ionic. What property of water allows these substances to dissolve and make water a good solvent?

Which bond is broken when ATP is used?

What type of molecule is part C ?

Which pair of scientists proved the method by which DNA replicated?

Which molecules bind to the exposed bases when DNA becomes single stranded?

Which of the following is not true of RNA?

Name the pentose sugar found in DNA.

On the above diagram, name the group labelled A

DNA and RNA are both polymers of which monomer?

Which points on the above graph show when the enzyme is denatured?

On the above diagram, which letter represents the activation energy without an enzyme?

Enzymes speed up chemical reactions by doing what?

What colour shows a positive result?

What is the name of the biochemical test for proteins?

What is the name of this molecule?

What substance is added to the sample at the start of a test for lipids?

Fats that contain unsaturated fatty acids (compared to saturated) are more likely to have:

Which of these three molecules is a fatty acid?

What is the formula for glycerol?

Is one of the monomers beta glucose ?

True or False - Each B cell has an antibody with a different shaped variable region on its membrane.

A doctor vaccinated a group of patients against poliomyelitis. He gave each patient two doses of vaccine, 3 months apart. Calculate the percentage increase in the mean concentration of antibodies in blood between samples 2 and 3.

NMO is a disease NMO is a disease that leads to damage to nerve cells in the spinal cord. A person with NMO produces anti-AQP4 antibody that attacks only these nerve cells. Explain why the anti-AQP4 antibody only damages these cells