Biology Random Retrieval

How many chromatids are present in a human cell at the start of meiosis?

What is a difference between RNA and DNA?

Water molecules stick together due to what type of bond?

What has happened at position A?

What do we call the arteries which supply the heart muscle?

In which direction ( if any), would a curve be for diving seal haemoglobin?

The blood and water flow in opposite directions, what is this called?

Which muscles contract during forced expiration?

Which type of cell activates other immune cells in an immune response?

A worm native to fresh water will die when placed in sea water. Why is this?

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

What type of molecules are most likely to pass through C?

What happens in G1 phase?

What type of molecule is part C ?

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

If everything else was kept the same, what effect would adding more enzyme have on the position of the line?

On the above graph, lines A and B represent the same enzyme, in identical conditions; the only difference is the temperature.

What would happen to the red line after this point ?

On the above diagram, which letter represents the product?

What would the products be from the hydrolysis of sucrose?

Are molecules A,B and C isomers of each other?

Are the bonds between water molecules stronger or weaker than covalent bonds?

What charge will be on the hydrogen atoms in this molecule?

How many bonds form between the Bases C and G when the base pair?

On the above diagram, name the group labelled C.

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?

If everything else was kept the same, what effect would adding more enzyme have on the position of the line?

On the above graph, lines A and B represent the same enzyme, in identical conditions; the only difference is the temperature.

What would happen to the red line after this point ?

Which letter on the above graph shows when the most enzyme-substrate complexes will be formed?

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

What is the area of an enzyme called where the substrate binds?

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

What is the name of the biochemical test for proteins?

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

What is the name of the bond that forms between two amino acids?

What is the name of the NH₂ group on an amino acid molecule?

Which best represents the hydrophobic area on this diagram?

If this diagram represented the plasma membrane of an epithelial cell in a human small intestine. What solutions would be on side'a' and side 'b'?

Which of these three molecules is a fatty acid?

Which polysaccharide do animal cells use as storage?

Which elements are found in carbohydrates?

Which is the variable region on the above diagram?

True or False - Plasma cells are clones.

Digested pathogen proteins can be displayed on the cell surface membrane of a phagocyte. What is this called?

Type your answer.

Which term describes a solution with a lower water potential than the cells bathed in it?

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

What type of transport is osmosis?

Which type of membrane protein is not involved in facilitated diffusion?

Which part of the phospholipid bilayer prevents sodium ions leaving via simple diffusion?

Name structure G.

Name the part of molecule J, which makes up part B.

How long is one complete cell cycle on this graph?

What happens in S phase?

Which organelle will be found in supernatant C?

What does SEM stand for?

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

What is structure F called?

Name the function of organelle A

This is found inside most eukaryotic cells, what is C ?

This is found inside most eukaryotic cells, what is A?

What is the function of this organelle?

At the sink, solutes are removed from the phloem, what effect does this have on water movement?

Water molecules stick together due to what type of bond?

The evaporation of water molecules out of the leaf, 'pulls' the water molecules behind up. What is this 'pull' called ?

Xylem or Phloem ? - No end plates on these cells

What is a Thrombosis?

What is an Atheroma?

Which chamber do you think the green line represents?

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?

What do we call the arteries which supply the kidneys?

In the diagram of the human circulatory system, which letter represents the Pulmonary Vein?

If Carbon Dioxide concentration increases, which letter shows the direction the curve will shift?

What unit do we use to measure the concentration of oxygen in the tissue?

Why is haemoglobin described as being 'Quaternary'?

What is the function of the lamellae?

Using the diagram, which part is a gill filament?

Forced Expiratory Volume (FEV) is the maximum volume of air that can be breathed out in 1 second. What is the FEV for person B?

Pulmonary Ventilation Rate ( PVR) -= Tidal Volume x breathing rate. If someone take 60 breaths over 5 minutes, and takes in 230 cm³, what is their PVR?

Which letter represents the diaphragm?

Why can single celled organisms exchange many substances by simple diffusion over the plasma membrane?

A Palisade cell is rectangular, and measures 100 µm by 40 µm. What is its surface area?

True or false : The most effective antibiotic for E Coli O121 will also be the most effective antibiotic for EColi K1.

How do Microbiologists test for bacterial susceptibility to antibiotics?

The development of antibiotic resistance is an example of what type of selection?

The Amish in America are a closed community, which only reproduce with-in their own population. They are descended from 200 Swiss who migrated there. They have a much higher proportion of alleles which cause genetic disorders, rarely seen in the rest of the population. What is this an example of?

True or false : The Founder Effect is a type of genetic drift?

In Biology, what does genetic diversity represent in a population?

Which of the following can be a mutagenic agent?

What type of mutation is this ? ACCTGG becomes ACTGG

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

On this diagram, what does D represent?

On this diagram, what does B represent?

What molecule is formed at the end of translation?

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

Which is the true statement about DNA compared to RNA?

What word describes the fact there is more than one set of three bases for each amino acid?

DNA is read in sets of three bases called what?

What do H and h represent?

How many chromosomes do most human cells contain?

Which word does NOT describe the genetic code?

True or False : The sex chromosomes ( X and Y) are an homologous pair?

Why do we need two primers in PCR?

If the same restriction enzyme is used to make two fragments, what can form between the exposed bases on each end if they are mixed with each other?

What is an advantage of using iPS cells to treat degenerative disorders, instead of embryonic stem cells?

Which molecule does the SIRNA / protein complex (RISC) bind to?

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

True or false: Succession only happens on land?

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?

Which type of selection is shown by fossils of black bears, showing them becoming bigger during glacial periods ( ice ages)?

What is the definition of 'heterozygous'?

Axons with a wider diameter axon have...

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?

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

True or false : Kinesis is a random movement

True or False : Kinesis is a directional response to a stimulus.

Which of these statements about Went's experiment is NOT true?

How does IAA become unevenly distributed?

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

Which wavelength of light would the rate of photosynthesis be lowest in the above experiment?

The transfer of electrons along the carrier proteins causes hydrogen ions to be moved across the membrane, causing a proton concentration gradient. the protons than pass back through the membrane creating ATP. What is the name of this process involving using electrons to produce a concentration gradient?

In non-cyclic photophosphorylation, the electrons that leave the chlorophyll are replaced by the splitting of water. What is the name of this process?

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

What is 'Guano'?

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

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

The diagram shows a food web found in the arctic. the producers have a net productivity of 4.52 x 10 ^-3 kJ m^-2yr^-1-2yr^-1

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

What would be the most appropriate units for measuring biomass?

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

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

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

Which part of the mitochondria is represented by B?

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

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 Oxaloacetate produced by cells exposed to IDH1 ?

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

Name the above process: The ______ _________

In the above experiment, chloroplasts were isolated from plants grown at different light intensities. What is the saturation point of Normal plants grown in high light?

In the above experiment, what measurements should the student take to measure the rate of photosynthesis?

What does substance H do to substance B?

Name molecule F

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

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

The image above shows a muscle fibre. Name organelle C

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.

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

What effect do inhibitory synapses have on the post-synaptic membrane?

Whether a synapse is excitatory or inhibitory depends on what?

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

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

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

What is the main function of the fatty substance wrapped around peripheral nerve axons?

Why can't a second action potential pass immediately after the first ?

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

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?

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?

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

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?

Plant responses to stimuli are controlled by what?

True or false: Succession only happens on land?

What is the native climax community in the UK?

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

What do we call a stage of succession?

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

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

Which of the following is an abiotic factor which effects population size?

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?

Which type of selection is human birthweight showing? (As low birth - weight babies and high birth - weight babies are less likely to survive)

What type of variation is show in the graph?

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, split into two groups?

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?

What does 'p' represent ?

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

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?

Which sex is the carrier of sex lined genes?

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)?

What do we call it if the restriction enzyme cuts both strands of DNA in a staggered position to create an overhang?

How would the cDNA base sequence of a gene differ to the normal genomic base sequence of a gene?

What causes epigenetic markers to be added or removed from DNA?

What is 'Epigenetics'?

Cardiomyocytes are an example of what type of stem cell?

Which type of stem cells are not found in adults?

What does the RISC complex do to the mRNA?

Which molecule does the SIRNA / protein complex (RISC) bind to?

What forms the substrate in a Transcription complex formed from OOR and RNA Polymerase?

Where is the oestrogen receptor located?

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 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?

TTA = Leu TTG = Leu TTC = Phe TCA = Ser TAA = Stop What would be the order of amino acids in a polypeptide coded from this sequence?

TTCTTGTTATCATAA

What is the position of gene on a chromosome called?

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?

Name the method by which DNA replicates.

Which of the following is NOT a difference between RNA and DNA?

What does the C stand for in the genetic code?

Name the components of a DNA nucleotide.