Biology Random Retrieval

During Metaphase 1, the homologous pairs can line up with either the paternal chromosome above, or the maternal chromosome above. What is this phenomenon called?

What does the 'm' stand for in mRNA?

Which would not increase the volume of water transpired by the plant?

Through which part does the water evaporate out of the leaf?

What is the stroke volume of a patient if their cardiac output is 3500 cm³ min^-1, and their heart rate is 70 bpm?

Why do the guard cells become 'curved' when they swell up?

What maintains the concentration gradients for gaseous exchange in the tracheoles?

Why might the FEV be lower for person B?

Some animals are adapted to higher temperatures in their environment. Which of the following is an example of this ?

In the above experiment, why would the student be advised to take repeat readings?

In the above diagram, there are three membrane proteins: A, B and C. Which represents where facilitated diffusion occurs?

Why can't glucose diffuse directly through the phospholipids?

Which is the best explanation for the effect of ethanol on membrane permeability?

Name structure G.

Which type of electron microscope show the density of the specimen as a dark patch?

Name this organelle.

Viagra is a similar shape to cyclic GMP ( cGMP). Both will block an enzyme called PDE5. cGMP causes vasodilation. What sort of inhibitor is Viagra?

Other than peptide bonds, a folded protein also contains:

i) Hydrogen Bonds
ii) Ionic Bonds
iii) Di-Sulphide Bridges.

Which bonds form the secondary structure?

What is the formula for glycerol?

What elements are lipids made out of?

Which of the following molecules contain a phosphate group?

Which equation represents the action of ATP Synthase?

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

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 pair of scientists proved the method by which DNA replicated?

Penicillin works by binding to an enzyme called transpeptidase in bacteria, changing the shape of the active site. When penicillin binds, it means the bacteria can no longer make cross-bridges in the bacterial cell wall. What type of inhibitor is penicillin?

Explain why line B forms a plateau:

Which of the following is true, in the currently accepted model of enzyme action?

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 are biological catalysts: they speed up reactions. This allows the reactions to happen at...

What is the next reagent to be added after this initial treatment?

How many naturally occurring amino acids are there in all living things?

What type of bond joins a fatty acid to a glycerol molecule?

Which polysaccharide do animal cells use as storage?

What feature does this polysaccharide have, that makes it straight?

Which two types of polysaccharide form starch?

What would the products be from the hydrolysis of sucrose?

Which disaccharide is made from glucose and galactose?

What type of bond forms between two monosaccharides?

Which molecule is NOT glucose ?

A doctor vaccinated a group of patients against poliomyelitis. He gave each patient two doses of vaccine, 3 months apart. Explain the differences between the mean concentrations of antibodies in blood samples 1 and 2 .

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

What happens to a B lymphocyte when it is activated?

On the diagram above, which structure is a lysosome?

Look at the above graph, what is the concentration of sodium chloride inside the potato cells?

When investigating osmosis, why is it better to calculate the percentage change in mass, rather than just the change in mass?

Is a higher water potential...

What type of transport is osmosis?

Other than glucose, which substance can be absorbed from the ileum via co-transport?

Which protein needs to be used first in the co-transport of glucose across a membrane. For example in the ileum.

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

True or False: Facilitated diffusion can use ATP

In the above experiment, two flasks contained identical masses of animal tissue, identical volume of a solution containing sodium ions, but an inhibitor of ATP production in flask F. Scientists concluded that flask G took up sodium ions by active transport. What is the evidence of this?

a) Uptake in flask G much greater than in flask F , showing use of ATP in flask G

b) Sodium ion concentration in flask G falls to zero, showing uptake against a concentration gradient

What substance will structure C be made out of?

Which organelle will be found in pellet A?

To look at a sample under a microscope, you need to prepare a temporary mount. Why does the specimen have to be thin?

Which of the following is equivalent to 1mm x 10^-4 ?

Name this organelle.

What are the inner membrane folds called in this organelle?

Name this organelle.

Which of the following is an example of a 'sink' ?

Which would not increase the volume of water transpired by the plant?

What term is used to describe the 'sticking' together of water molecules?

Why are the Atrioventricular valves open at D?

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

What has happened at position B?

Cardiac Output ( CO) = Stroke Volume (SV) X Heart Rate ( HR). What is the cardiac output of an athlete with a SV of 95 cm³ , and a HR of 52 bpm?

Name the structures labelled B

Which type of blood vessel has the thickest muscular layer?

On the graph, which letter shows where it is hardest for oxygen to associate?

Why is haemoglobin described as being 'Quaternary'?

What is a xerophyte?

Which number represents a layer which is 2 or 3 times thicker in desert plants?

Which letter is the tracheae?

Emphysema is caused by what?

What does Pulmonary Ventilation Rate (PVR) mean?

Some animals are adapted to a lower environmental temperature. Which of the following is an example of this?

Some animals are adapted to higher temperatures in their environment. Which of the following is an example of this ?

Multicellular organisms cannot absorb enough substances by diffusion. Why is this?

Is it important which way round the numbers go when writing a ratio?

How do Microbiologists test for bacterial susceptibility to antibiotics?

Why do most mutations cause a decrease in reproductive success?

Why do the modern day population of Tristan De Cunha has a much higher than average incidence of the genetic disorder Retinitis Pigmentosa?

Tristan De Cunha is an island populated by a small number of Britons in the early 1800's. What is this an example of ?

What happens to the number of different alleles during a genetic bottleneck?

Some gene mutations will have no effect at all on the polypeptide, why not?

Which of the following gene mutations will have the least dramatic effect on the polypeptide produced?

What type of mutation is this ? ACCTGG becomes ACCTTGG

The goat cardiomyocyte has 30 pairs of chromosomes. How many chromatids will be present in each cell formed at the end of meiosis Telophase 2?

How many different combinations of maternal / paternal chromosomes are there if there are 23 pairs?

How is variation introduced during prophase 1?

Is Anaphase 2 more similar to Anaphase 1, or Anaphase in mitosis?

How does metaphase 1, differ from metaphase 2 in meiosis?

What word describes cells which contain single chromosomes?

What molecule is formed at the end of translation?

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

Which bonds are broken by the enzyme used in transcription?

On this diagram, what does C represent?

How would you describe the shape of prokaryotic chromosome, when compared to a eukaryotic chromosome?

Eukaryotic DNA is stored, wrapped around which type of protein?

Which type of mutation will not cause a frameshift?

Which direction can DNA polymerase only extend the new strand of DNA?

What does the C stand for in the genetic code?

True or false : Succession is the same as evolution.

Which statistical test would we use to see if the observed phenotypes are different from the expected phenotypes?

Which of the above diagrams represents either end of an 'A Band' in muscle?

Using the diagram, name B

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

True or false : Kinesis is a random movement

How does IAA bring about this effect?

The diagram shows an Arctic food web. Why is the energy efficiency between Forbs and Rock Ptarmigan lower than that between a Rock Ptarmigan and an Arctic Fox?

a) Because more of the body of the Ptarmigan is eaten than the Frobs.

b) Because more of the Ptarmigan is digested and absorbed (assimilated)

c) Because a Ptarmigan is bigger than a Forbs

It has been estimated that an area of 8000m² is needed to keep a cow. The productivity of grass in the UK is 18,000 kJ m^-2yr^-1

The diagram above shows anaerobic respiration in which type of organism?

What is the final electron acceptor of the ETC?

Which molecule is represented by Y?

Which wavelengths would the rate of photosynthesis be highest in the above experiment?

A buffer was not used in the above experiment, what would happen to the pH during the experiment.

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

What type of molecule will pick up the 'high energy' electrons in PSII?

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

What is 'Guano'?

The above diagram shows the Phosphorus cycle. Name type of organism which carries out process A?

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

What does GPP stand for?

Anaerobic respiration allows the regeneration of NAD+ in all organisms, which allows glycolysis to continue. How many ATP's are gained during anaerobic respiration of one glucose molecule?

The diagram represents anaerobic respiration, name substance 'Z'.

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 this the correct equation for anaerobic respiration in yeast cells? : Glucose → Carbon Dioxide + Water + Ethanol

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

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

What should go in box 'X'?

As the ETC flows, what will happen to the pH of A?

Which of the following substances is NOT a co-enzyme?

Where does the Electron Transfer Chain ( ETC) occur?

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 concentration of Acetyl Co A produced by cells exposed to IDH1?

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?

Where does the Krebs Cycle occur?

How do you calculate the Rf value for a substance?

A buffer was not used in the above experiment, what would happen to the pH during the experiment.

High energy' electrons leave the chlorophyll molecule: What state does that leave the chlorophyll molecule in?

Name the molecule that carries out the function : Attaches to the Z line at the end of the sarcomere.

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

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?

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

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

Why is the speed of conduction faster on myelinated neurones?

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

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

Which direction are the ions 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

How can charged ions cross a plasma membrane?

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

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

Blow fly maggots have a light sensitive spot on their head, which they use to move away from light. Is this taxis or kinesis?

What is the definition of a stimulus?

What does Boysen and Jensen's experiment using agar show?

Which of the following is true?

What affect does IAA have on shoot tips?

What response do roots have to light?

What is a growth response to light called?

Between stages D and E, what will happen to light intensity at ground level?

What term do we use to describe lichen and mosses in succession?

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?

How many samples should you take to get reliable data?

Which of the following isn't an example of genetic drift?

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

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?

Which type of selection is shown by Darwins finches, where small and large beaks were both at an advantage due to different food sources?

Which type of selection is when the number of individuals with a particular characteristic, increase around an extreme or outlier value?

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 is the allele frequency ( as a decimal) of the light allele in the population?

Drosophila is a type of fruit fly which is used in many genetic experiments. It has two alleles for eye colour : Red ( R) and White (r). If 0.8 of the alleles are red, how many are white?

What does 'p' represent ?

What is the probability of a colour- blind father and a homozygous dominant female having a colour blind child?

A codominant allele' is when both alleles are expressed. One breed of chickens can have Black feathers(B) or White feathers(W). What phenotype will a chicken have with the genotype BW ?

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 proportion of the offspring of a heterozygous father (TtVv) and a heterozygous mother (TtVv) will be health and have a V shaped 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?

What is the definition of 'heterozygous'?

What is the definition of 'phenotype'?

What is a gene?

What enzyme is needed in a PCR reaction ?

If a bacterium contains a recombinant plasmid, then it will express the new 'foreign' gene as well as it's own. Which of the following is not a product made by recombinant bacteria?

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 it if the restriction enzyme cuts both strands of DNA in the same place?

What is 'Epigenetics'?

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

What type of hormone is oestrogen?

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

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 amino acid 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.

Which enzyme is used during transcription?

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

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.

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: TTCTTATTATCATAA.

Will this mutation affect the primary structure of the polypeptide ?

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

If a section of DNA contains 21% base C, what percentage will base A have?

True or False: DNA polymerase requires double stranded DNA in order to initiate DNA replication

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

Name the components of a DNA nucleotide.