Biology Random Retrieval

How is variation introduced during prophase 1?

The Mass Flow Hypothesis, is the best explanation for translocation in plants. What does it suggest happens at 'sources'?

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

What is the tap and water reservoir above it for?

Which of the following is a way a high salt content in your diet increases your risk of developing CVD?

What happens during Ventricular Systole?

What term describes the haem groups which contain iron?

Haemoglobin is a quaternary protein, how many polypeptide chains make up a single molecule of haemoglobin?

Why does the blood flow in an opposite direction the the water?

Pulmonary Ventilation Rate ( PVR) -= Tidal Volume x breathing rate. If the breathing rate is 7, and the PVR is 1.4 dm³ min ^-1, what is the tidal volume?

What is the correct term for the cells which make up the alveolar wall?

Cresol red is an indicator which goes clear at a low pH. A plate of agar jelly with cresol red added was made, and two blocks were cut out. Block A measured 10mm x 10mm x 10mm. Block B measured 20mm x 7mm x 7mm. Which one will decolourise quickest when placed in an acidic solution ?

Which type of electron microscope produced this image?

The image shows palisade cells in a leaf. Line B (length) in the image measures 3.5 cm, and the actual cell measures 7μm. What is the magnification of this image of the palisade cell?

Which of the following organelles has a different structure in prokaryotes when compared to eukaryotes.

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

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

What base does the 'A' stand for?

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

Which disaccharide is made from glucose and galactose?

What type of reaction is involved in the breakdown of ATP?

What is the name of molecule B?

If DNA replicated by a Conservative method, what would the DNA bands look like after one generation in N¹⁴ medium(Tube A)?

What name is given to the DNA fragments labelled C in the diagram?

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

What type of bonds are broken between the DNA bases when replication starts?

Which bonds are disrupted by changes in pH?

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

What substance are enzymes made out of?

What is the name of the biochemical test for proteins?

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?

More than two amino acids joined together is called what?

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

Which of the following terms best describes the phosphate part of a phospholipid?

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

The 'tail' of a fatty acid can be a variable length molecule. But what type of molecule is the tail?

What is the formula for glycerol?

Name the polymer in the picture.

What type of bond forms between two monosaccharides?

Which molecule is Beta - Glucose?

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

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

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

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

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

Why can't glucose diffuse directly through the phospholipids?

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

a) Oxygen
b) Carbon Dioxide
c) Lipids

Why can more pigment leak out across the plasma membrane at a higher temperature (80⁰C) ?

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

Name molecule J (Spell it correctly)

To perform a 'Root Tip Squash' , what do you have to do to your root tip cells prior to staining?

Name the area where the sister chromosomes together, and attach to the spindle fibres here. (Spell it correctly)

Between which times does synthesis take place?

What term is given to describe G1 phase, S phase and G2 phase combined? ( Spell it correctly)

Why must the solution used to homogenise be cold?

Which organelle will be found in pellet A?

To look at a fresh sample under a light microscope, you'll need to prepare a temporary mount. What is NOT used to stick the specimen to the microscope slide?

Which type of electron microscope can only be used on non-living samples?

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

What substance is layer B made out of?

In the mass flow hypothesis, the water potential is reduced in the phloem near the sources. What will happen to water movement?

In terms of translocation, what is an 'assimilate'?

What is the tap and water reservoir above it for?

What is transpiration the movement of?

Xylem or Phloem ? - No end plates on these cells

Which of the following is a way a high salt content in your diet increases your risk of developing CVD?

What has happened at position D?

What has happened at position A?

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?

Does this bar cart show a correlation between number of cigarettes smoked, and the risk of CVD?

Which type of blood vessel has a folded endothelium?

In which direction ( if any), would a curve be for humming bird haemoglobin?

Where in a human, is the affinity of haemoglobin for oxygen the highest?

Using the diagram, which part is a gill filament?

What is 'Tidal Volume'?

Sufferers of emphysema also have reduced elastin in the alveolar walls. What effect does this have on breathing?

Which of the following is the correct sequence for inhalation?

How have multicellular organisms adapted to not being able to absorb everything via diffusion over their surface?

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?

What technique is required when culturing bacteria?

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

How do new alleles occur in a population?

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

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

Which of the following is true about all mutagenic agents?

Which of the following is a mutagenic agent?

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?

What is the order of events from the diagram for Meiosis division 2?

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

What word describes cells which contain pairs of chromosomes?

As the mRNA is fed through the ribosome, complementary base pairing between the mRNA and tRNA mean that amino acids are lined up in a specific order. What level of protein structure is established here ?

How many tRNA molecules can fit into a ribosome at any time?

Where does the enzyme used in transcription bind?

Which bonds are broken by the enzyme used in transcription?

Which is the true statement about DNA compared to RNA?

On this diagram, what does B represent?

What is an 'homologous chromosome'?

What is the position of gene on a chromosome called?

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

Which area of DNA is particularly affected by methylation?

What are iPS cells?

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

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?

What represents the total allele frequency in a population?

The actual ratio of phenotypes after several matings between the above two hamsters was more similar to 6:1:1:6. How are the alleles linked?

The image above shows a muscle fibre. Name organelle C

What the the tiny gaps called labelled X on the above diagram? ( Type your answer)

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

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

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

Which of the following is an example of a plant growth factor?

Which term describes an organism which feeds on dead organic matter and digests their food externally? (watch your spelling)

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 above shows anaerobic respiration in which type of organism?

Once 'W' reaches protein complex VI, what does it combine with to form water?

Isocitrate dehydrogenase is an enzyme used in the Krebs cycle to convert Citrate into the 5C intermediate. IDH1 is an inhibitor of Isocitrate dehydrogenase. If IDH1 acted as a competitive inhibitor of the enzyme, how would it reduce enzyme activity?

How do you calculate the Rf value for a substance?

How many turns of the Calvin Cycle are required to balance the number of carbon atoms to produce one glucose molecule?

Which letter represents a lamella?

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.

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?

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

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?

Which of the following is NOT an accurate way of measuring biomass?

Which direction would the bubble move in the above experiment?

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

Where does the Electron Transfer Chain ( ETC) occur?

How many reduced NADs have been produced from one glucose molecule by the end of the link reaction?

Why did the student set up tube 1?

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

In the above experiment, a 'starting line' is drawn in pencil. What is the name of the starting line - The ______(spell it correctly!)

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?

What does substance H do to substance B?

Name molecule F

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

Where in a chloroplast do the Light Independent Reactions ( LIRs) occur? ( watch your spelling!)

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

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

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.

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 gives rods high sensitivity compared to rod cells?

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

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

If the concentration of neurotransmitter secreted is very low, then threshold may not be reached. What term describes the process of increasing neurotransmitter release? either by multiple presynaptic neurones forming a single synapse or increasing the frequency of neurotransmitter release. Type your answer

Whether a synapse is excitatory or inhibitory depends on what?

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

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

Using the diagram, name C

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

Axons with a wider diameter axon have...

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

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:

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

Put the above events ( A-F) in order for the passage an action potential.

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

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

What response do roots have to light?

What is the native climax community in the UK?

Which factor will the lichen and mosses change the most?

At which stage will abiotic factors be most hostile?

What is the biological meaning of succession?

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?

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?

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?

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

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.

Natural Selection means that over time the frequency of beneficial alleles in a population will do what?

What is 'crossing over'?

Which of these is a source of variation?

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?

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?

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

What is the definition of 'allele'?

What is the definition of 'genotype'?

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

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

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?

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

What is 'Epigenetics'?

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

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

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

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 molecule is created during transcription?

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.

What type of mutation has occurred ?

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 does the term 'Degenerate' mean when referring to the genetic code?

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.

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

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

Name the type of bond which forms the backbone of the DNA strand.