Category: Biology

Primers are short single stranded pieces of complementary sequenced DNA. Which ISN'T a reason to add specific primers added to the PCR reaction?

In a PCR reaction, the DNA is heated at the start of the cycle to around 95 degrees C. What is the reason for this?

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?

We cannot see the proteins made by recombinant plasmids, nor the plasmids themselves. How do we know the bacteria have been transformed properly and contain a recombinant plasmid ( = plasmid and new gene fragment) ?

If we cut out a human gene using restriction enzymes and ligate it into a plasmid using ligase, then that plasmid is now 'Recombinant'. What do we call the process of putting the recombinant plasmid into bacteria?

Which bond to restriction endonucleases ( restriction enzymes) break?

Acetylation is the addition of a C2H3O group which contains a double bonded oxygen. Where does acetylation occur?

Which term is used to describe the full process of genetic code in DNA being turned into a polypeptide chain?

Which level of protein structure will the binding of oestrogen alter?

Where is the oestrogen receptor located?

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

What do we call a transcription factor that 'turns on ' genes?

Which molecule is created during transcription?

Which enzyme is used during transcription?

Long term exposure to Oestrogen can increase the risk of developing breast cancer. The exact mechanism is still not fully understood, but which of the following is definitely NOT a suggested mechanism ?

If hypomethylation (reduced methylation) happens to a proto-oncogenes gene, what effect will this have on the rate of mitosis ?

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?

Which of the following is a difference between prokaryotic and eukaryotic DNA?

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

Name the enzyme that breaks the hydrogen bonds between complimentary bases during DNA replication.

A student is using a quadrat to estimate percentage cover of clover on the school field. What is the most accurate way to do this?

Using mark release recapture, what would the population of woodlice be if : 27 were caught in the first sample , and 16 unmarked caught in the second, and 3 were marked?

What is the word used to describe 'All the different populations in a habitat along with all the abiotic conditions'?

What type of speciation is caused by a physical barrier between two populations such as a body of water?

What type of variation is show in the graph?

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?

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?

Which of the following is not a cause of variation?

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 Cystic Fibrosis is about 1 in 2500 in the UK. How many individuals will suffer with Cystic Fibrosis in a city of 1.2 million people in it's population?

An Ethiopian breed of cattle has low whey protein in its milk. This is controlled by a dominant allele (M). If 6 % of the herd have low whey protein, what proportion are heterozygotes?

Which part of the Hardy Weinberg equation represents the homozygous recessive individuals?

The Hardy Weinberg principle only applies to a population that is or has ____.

Being colour blind is a sex-linked disorder. What is the probability of an unaffected male having a colour- blind child with a heterozygous female?

Which sex is the carrier of sex lined genes?

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

Which chromosome carries the sex linked alleles?

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 ?

In guinea pigs, Short hair (S) is dominant to long hair (s). In a monohybrid cross between a heterozygous mother, with a heterozygous father, what ratio of long hair to short hair will the offspring have ?

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

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

In the above image, which type of protein makes up the myofilaments labelled C? type your answer in carefully.

The image above shows a muscle fibre. Name organelle E

What is the structural adaptation which give cones high visual acuity compared to rod cells?

Name part A on the above diagram.

Can the potential difference created by a receptor have different values depending on the size of the stimulus?

Doctors investigated two ways of measuring the effect of general anaesthetics. In one method they timed how long it took to stop blinking, and then repeated the investigation using a machine to record when brain activity showed they were unconscious. Blinking involves cholinergic synapses. Anaesthetic S is a similar shape to acetylcholine. Suggest how anaesthetic S stops the transmission across the synapse.

If a neurotransmitter binds to the post synaptic membrane and causes potassium ion channels to open, would it be excitatory or inhibitory?

On the diagram, which type of ion will D allow through when opened on an excitatory synapse?

Using the diagram, name D

Using the diagram, name C

Name the term given to the 'jumping' of an action potential long a myelinated neurone.( Type in your answer)

When an action potential is generated, there is a temporary reversal of the polarity of the neurone membrane at that point. Does this mean that:

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.

Which of the events ( A- F above) requires ATP ? ( Type the letter in the box)

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

The resting potential of a neurone is maintained in part, by the Sodium-potassium pump. But which of the following shows the correct movement of the ions?

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

Which of the following is true?

The concentration of nitrates and phosphates in the soil can be increased by the addition of fertiliser, but what ecological damage can this cause?

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

The diagram shows an Arctic food web. The arctic fox consumes a 35% share of the primary consumers, with the Gulls and skuas consuming 65%. The arctic fox achieves a 9% energy efficiency, from the total primary consumers productivity of 6,112kJ m^-2yr^-1. What is the productivity of the arctic fox?

In a woodland, 8,150 kJ m^-2yr^-1 is lost as heat from respiration. The gross primary productivity of the wood is15,000 kJ m^-2yr^-1. What is the net primary productivity of the woodland?

In this investigation, are the yeast respiring anaerobically or aerobically ?

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?

If oxygen isn't available, which substance cannot be regenerated in high enough amounts to keep the system running?

In which stage of respiration is oxygen required?

Is this the correct equation for anaerobic respiration in animal cells? : Glucose → Carbon Dioxide + Lactic Acid

How many molecules of ATP are generated by oxidative phosphorylation in the ETC from one molecule of glucose?

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

A single molecule of W is produced per turn of the Krebs cycle, and it carries hydrogen off to the ETC. What is it?

Name molecule X

Where does glycolysis occur?

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 substance is represented by I?

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

Name substance A

What does molecule 'H' represent?

Which term best describes what happens to the electrons when light hits the primary pigment (or reaction centre)?

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?

After fertilisation, zygotes ( fertilised eggs) divide by which process?

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

The deoxyribose sugar at the end of a DNA molecule can either have a bond available to join with carbon number 3 ( 3' or 3 prime) or carbon number 5 (5' or 5 prime). DNA polymerase can only join to one end, which end can it bind to and then extend?

Is the following an 'Abiotic adaptation' or a 'Biotic Adaptation': The Warbler Finch has a short slender beak for catching insects whilst, flying. Where as the Large Ground Finch has a strong , deep beak for crushing seeds.

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

Marfan syndrome is a dominant inherited disorder, where the suffer develops an increase in a growth factor ( TGF - beta) which effects connective tissue. What is the probability of a healthy mother and a heterozygous father having a healthy child?

In guinea pigs, Short hair (S) is dominant to long hair (s). In a monohybrid cross between a heterozygous mother, with a heterozygous father, what ratio of long hair to short hair will the offspring have ?

What is the best definition of a 'recessive allele'?

The plasma membrane of a neurone at rest is most permeable to which ions via facilitated diffusion?

Put the following into the correct order:

a) Lower plants die due to lack of photosynthesis.
b)Fish die due to lack of dissolved oxygen.
c) Decomposers respire aerobically to decompose the dead plant matter.
d) Increased algae blocks out the light.
e) Minerals leach into the waterway.
f) Increased minerals cause an algae to grow rapidly.

Many decomposers secrete enzymes to digest organic matter, then absorb the products they require. The digested products which are not required remain in the soil. The digestion of which organic substance will result in the presence of ammonia in the soil?

The diagram shows an Arctic food web. The arctic fox consumes a 35% share of the primary consumers, with the Gulls and skuas consuming 65%. The arctic fox achieves a 9% energy efficiency, from the total primary consumers productivity of 6,112kJ m^-2yr^-1. What is the productivity of the arctic fox?

What does GPP represent in a given area?

How many molecules of ATP are generated in aerobic respiration from one glucose molecule entering glycolysis, to the end of the ETC?

If 5 glucose molecules are respired, how many molecules of CO₂ will be produced from Glycolysis, Link reaction and the Krebs cycle?

How many molecules of Y will be produced by the krebs cycle from a single molecule of glucose?

What is the net gain of molecule Y at the end of glycolysis?

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!)

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?

Which bond to restriction endonucleases ( restriction enzymes) break?

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

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

What is it called when succession is stopped artificially?

Which factor will the lichen and mosses change the most?

Population growth can be exponential . How would we turn a curved population curve into a straight line graph?

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?

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. How many are heterozygotes?

Being colour blind is a sex-linked disorder. What is the probability of an unaffected male having a colour- blind child with a heterozygous female?

On the diagram, which type of ion will D allow through when opened on an excitatory synapse?

This diagram shows part of the nitrogen cycle. Which two processes form nitrification?

The diagram shows an Arctic food web. The arctic fox consumes a 35% share of the primary consumers, with the Gulls and skuas consuming 65%. The arctic fox achieves a 9% energy efficiency, from the total primary consumers productivity of 6,112kJ m^-2yr^-1. What is the productivity of the arctic fox?

What is the formula for NPP?

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

Which part of the mitochondria is represented by B?

Isocitrate dehydrogenase is an enzyme used in the Krebs cycle to convert Citrate into the 5C intermediate. IDH1 is an inhibitor of Isocitrate dehydrogenase. What would happen to the volume of Carbon dioxide produced by cells exposed to IDH1?

What is the net gain of molecule Y at the end of glycolysis?

How many carbons are present in triose phosphate?

The above diagram shows the phosphorus cycle. Name process B

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

True or False : Fungi can increase the uptake of water by a plant

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

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

The above table shows the volume and density of a fresh wood sample, then the volume and density of the same sample after it was dried. Calculate the percentage of water in the sample (water weighs 1g / ml)

What does GPP represent in a given area?

Which direction would the bubble move in the above experiment?

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?

What happens to molecule C?

Molecule B enters the Krebs cycle from the link reaction, what is it ?

What is represented by molecule D?

What happens to molecule X after it has been generated?

If 'X' on graph A represents 'Light Intensity', what effect would increasing carbon dioxide have on the line (represented in green on the diagram)?

The solution in the above experiment had the same water potential, why is this important?

Other than temperature and pH, give two factors that the student should keep constant in the above experiment.

How many molecules of ATP are required to generate TWO molecules of glucose ?

What does substance H do to substance B?

Once light has hit structure D, and the electrons have left the chlorophyll, they can either be passed on to form F or follow path 'G'. What is path 'G'?

Which of the following is a feature of fast twitch muscle fibres when compared to slow twitch.

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

The image above shows a muscle fibre. Name organelle E

The table shows the results on investigating how fast an anaesthetic works. Using the results from the machine, was there a significant difference between anaesthetics S and Q?

Synaptic knobs contain mitochondria, which of the following is NOT a use of ATP in the presynaptic neurone?

Put the following statements in order to explain what happens at an excitatory synapse:

• a) Voltage gated calcium channels open.
• b) Synaptic vesicles fuse with the pre-synaptic membrane
• c) If threshold is reached, an action potential is generated
• d) Calcium ions diffuse into the presynaptic neurone.
• e) Arrival of an action potential
• f) Neurotransmitters bind to receptors with associated sodium channels
• g) Neurotransmitters diffuse across the cleft
• h) Sodium ions diffuse into post synaptic membrane

Using the diagram, name C

Axons with a wider diameter axon have...

Name the term given to the 'jumping' of an action potential long a myelinated neurone.( Type in your answer)

Which of the events ( A- F above) requires ATP ? ( Type the letter in the box)

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

Across a resting human neurone plasma membrane, what is the average potential difference?

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

In the above experiment on woodlice, how would you make the method more valid?

What piece of equipment do animal scientists use to investigate the effect of different stimuli on invertebrates?

Woodlice are more stationary with increased humidity. Is this taxis or kinesis?

Maggots follow a scent up a concentration gradient towards a food source. Is this taxis or kinesis?

Mica is like thin glass, and is impermeable to most substances. What does Boysen Jensen's experiment inserting mica show ?

What word describes the growth response of a plant to a stimulus?

Plant responses to stimuli are controlled by what?

Which of the following is an example of secondary succession?

What do we call a stage 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?

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

What would you press to show a bacterial population graph , plotted with a log 10 scale, back into actual bacterial population?

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

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

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

What type of speciation is caused by reproductive Isolation, but without a physical barrier between two populations?

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?

A group of organisms of the same species living in a particular area at a particular time' is the definition for what?

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?

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?

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 ?

Marfan syndrome is a dominant inherited disorder, where the suffer develops an increase in a growth factor ( TGF - beta) which effects connective tissue. What is the probability of a healthy mother and a heterozygous father having a healthy child?

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 long haired and ginger?

What is the best definition of a 'recessive allele'?

What is the definition of 'allele'?

Why do we need two primers in PCR?

PCR is an example of what type of DNA amplification?

We cannot see the proteins made by recombinant plasmids, nor the plasmids themselves. How do we know the bacteria have been transformed properly and contain a recombinant plasmid ( = plasmid and new gene fragment) ?

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

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

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

What does the RISC complex do to the mRNA?

What type of hormone is oestrogen?

What do we call a transcription factor that 'turns off ' genes?

What is the difference between mRNA and pre-mRNA?

Long term exposure to Oestrogen can increase the risk of developing breast cancer. The exact mechanism is still not fully understood, but which of the following is definitely NOT a suggested mechanism ?

Which of the following would have the most dramatic effect on the primary structure of the polypeptide produced?

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?

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

Which of the following carries the code for the order of amino acids?

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

Which of the following is a difference between prokaryotic and eukaryotic DNA?

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

What does the A stand for in the genetic code?

What is the name of the modification of pre-mRNA in eukaryotes?

Xylem or Phloem ? - This type of cell is carries dissolved organic substances both up and down the plant

Which of the following IS NOT a way that smoking contributes to the risk of CVD?

Name the structures labelled B

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

Is there a significant difference between risk of CVD smoking -19 cigarettes a day and more than 20 cigarettes a day?

What is it called, when Carbon Dioxide causes the dissociation curve to shift?

Which is an example of a behavioural adaptation which allows an animal to live at hotter temperatures?

Read the above passage. Before reweighing, the potato was blotted dry. Which of the following is NOT a reason for doing this?

Would the number of carrier proteins present affect the rate of active transport across a membrane?

If you were to investigate mitosis in plant tissue, which part of a plant would you choose to look at?

Assume the scale bar in this image is 2cm long, what is the magnification of this image?

Bacterial cell division creates.

True or False: The circular chromosome can only replicate once per division, but the plasmids can replicate multiple times.

What word best describes this molecule?

In this experiment, bacteria were grown for many generations in a medium containing N¹⁵. The bacteria were then removed from the N¹⁵ , and placed in medium containing .N^14.. When The DNA from this first generation was centrifuged ( tube A), what pattern did the DNA bands form?

Which of the following is not true of RNA?

The two strands in DNA are 'antiparallel'. What does antiparallel mean?

Glycine and Alanine are two common amino acids. How are their structures different to each other?

Is one of the monomers beta glucose ?

Which of the following molecules contain a phosphate group?

ATP can be used to add a phosphate group onto molecules. What is this process known as?

In a section of double stranded DNA, there were 62 bases. Of these, 20 were A. How many of the bases were T?

The direction each DNA strand is facing is often called 5 prime (written 5') or 3 prime (written 3'). What does this refer to?

What base does the 'A' stand for?

Explain how non-competitive inhibitors reduce rate.

Will line A ever plateau if the substrate is unlimited?

Which letter on the above graph is the ' Saturation' point?

In this reaction, what percentage difference in energy needed for an enzyme catalysed reaction, compared to an uncatalysed one?

What is the function of the active site?

a) To hold the substrate in such a way as to strain the bonds so they are easier to break. or
b) To hold the substrate in such a way, as to allow new bonds to form.

Enzymes speed up chemical reactions by doing what?

The structure of a protein relates to its function. What is the best description of a channel protein from the following?

Which is the correct structure for an amino acid?

Which best represents the hydrophobic area on this diagram?

On the above diagram, what does structure '2' represent?

Which of the above three molecules shows a correct bond between glycerol and a fatty acid?

What word best describes the fatty acid 'tails'?

Which polysaccharide do animal cells use as storage?

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

Which molecule is NOT glucose ?

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