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WBIO5/01 – Article potential questions

Biology A Level Tutor

Potential questions for the International Advanced Level Biology
Scientific Article for use with Question 7 – Unit 5

In Unit 5, the last question (question 7) is based on a pre-released scientific article; a total of 30
marks
...
The star-nosed mole has what is very likely the world’s fastest and most fantastic nose”
Scientific Article for question 7 for International Advance Level Biology - WBIO5/01
...

Delegation = A body of representatives
...

Ringed = Marked with or encircled by a ring or rings
...

Forelimbs = Either of the front limbs of an animal; a foreleg, wing, flipper, etc
...
What is the use of the appendages?
o Sensory organ
o To explore the environment
o Supersensitive organ
o As the mole is blind
2
...
Suggest what might be the selective advantage (the selection pressure) for the star-nose
evolving?
o The ability to detect
o And consume
o Small prey
o Rapidly
o In the dark tunnels

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WBIO5/01 – Article potential questions

Biology A Level Tutor

4
...
How does the star-nose function and what is it used for?
o Work as the eyes
o To sense and explore the environment
o To detect prey
o The nose has 22 appendages that are covered with thousand receptors
6
...
Define evolution?
o The gradual development of living organisms
o From earlier forms
o Over several generations
8
...
What is considered a mammal?
o Belongs in the Mammalia class
o Warm-blooded
o Higher vertebrates
o Nourish their young with milk secreted by mammary glands
o Have skin usually more or less covered with hair
...

Paragraph: 2
Murky = dark and gloomy, especially due to thick mist
...

Unsurpassed = Better or greater than any other
...
List the adaptations of the star-nose mole and how each one helps it survive
...
The Binomial System is used to name these animals
...

o The first part is the genus shared by all related species
o The second defines the particular species
...
Why is the use of the binomial system developed by Linnaeus an advantage?
o Because organisms are given a two-part Latin name
...

13
...

14
...
Scientists classify organisms into taxonomic groups such as three domains
...

o Organisms with specific common characteristics are placed in a group
o Characteristics are assessed and classification can be done based on observable
characteristics:
o Behavioural similarities,
o DNA similarities
o Molecular phylogeny
...
What is Taxonomy?
o The science of classifying living things

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WBIO5/01 – Article potential questions

Biology A Level Tutor

17
...

o This is the basis of a hierarchical classification system
o Kingdom
o Phylum
o Class
o Order
o Family
o Genus
o Species
18
...
Suggest why they have a high metabolism and a voracious appetite?
o High metabolism as they need high energy
o To keep warm (produce more heat energy)
o To move inside the tunnels
o Voracious appetite as they need food to get energy
o The more food they eat the more energy they acquire

20
...
What is molecular phylogeny and how can it be used to find
evolutionary relationships?
o The study of molecules, DNA, RNA, proteins
o To identify evolutionary relationships based on:
o The more sequences in common, the closer the relationship between the
organisms
o Based on DNA profiling/eq
o And sequences of bases in RNA or DNA
o And proteomics/ amino acid sequences
21
...
Explain in terms of its size and temperature why is has a high metabolism?
o It has a large surface are to volume ratio due to its size
o Thus, it losses heat (radiates heat)
o Also, losses heat as it leaves in cold wet weather
o So, needs high metabolism, to produce more heat energy
o To keep warm and survive
23
...
What type of neurones should be found on the star skin and why?
o Sensory
o To relay the information to the brain
25
...

Aggregation = A cluster of things that have come or been brought together
...
A bump
...

26
...

o Advantage:
o Huge powers of magnification
o Huge powers of resolution
o Disadvantage:
o All specimens are examined in vacuum
o Specimens undergo severe treatments which is likely to result in artefacts
o It is extremely expensive

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WBIO5/01 – Article potential questions

Biology A Level Tutor

27
...
The diagram below shows a typical animal cell as seen using an electron microscope
...

o G - Centrioles

29
...

o Made from three layers: epidermis, dermis and subcutaneous fat
o Epidermis is made from epiderma cells, that make the skin though and waterproof
30
...
What are touch receptors? And what is their function?
o They are nerve cells
o Send signals to the brain
o There are several types:
(1) Mechanoreceptors – Senses pushing, pulling or movement
(2) Thermoreceptors – sense temperature
32
...
Describe and explain the sequence of events that occurs at the synapse
...

33
...
What is a Sensory organ?
o A body structure that receives a stimulus
o It initiates a wave of excitation in an associated sensory nerve
o Which convey specific impulses to the central nervous system
o Where they are interpreted as corresponding sensations
35
...
What is the Eimer’s organs?
o Specialized epidermal
o Sensory receptors
o Domed shaped

10

WBIO5/01 – Article potential questions

Biology A Level Tutor

Paragraph: 4
37
...


38
...
What are Schwann cells? What is their function and structure?
o Wrap around the axon of the long nerves,
o Creating a thick layer of membrane,
o Which insulates the nerve
o Allows for much faster conduction speed
...


11

WBIO5/01 – Article potential questions

Biology A Level Tutor

40
...

o Idea that Schwann cells cover the axon
o Idea that myelin / Schwann cells provide insulation
o Action potential / depolarisation at nodes of Ranvier
o Idea that local currents occur over a longer distance
o Reference to saltatory conduction
o Impulse jumps from node to node
41
...
How are neurotransmitters released?
o Action potential / impulse causes influx of Ca2+
o Vesicles fuse with pre-synaptic membrane Or reference to exocytosis
o Idea that a neurotransmitter released and attaches to receptors
43
...
Describe the differences in the structure of a myelinated sensory
neurone and a myelinated motor neurone
o In sensory neurone:
o The dendron is longer
o The dendron is myelinated
o The axon is shorter
o Cell body not at the end but towards the middle
o Reference to no motor end plate being present
44
...
e
...
What is differentiation?
o Process by which less specialized cells become more specialized cell types
depending on the proteins they express
...
State the levels of organisation:
o Cell, tissue, organ, organ system, organism
47
...

o Organ has many functions and the tissue has one
o Organ gas many/several cell types/tissues, tissues has one/fewer cell types
48
...

o Both have cells working together /for same function
49
...
The human skin acts as a homeostatic organ, through the use of these receptors
...

Describe and explain how these signals can lead to temperature change through changes in
blood flow or sweating
...
Paragraph 4 states that “Both these receptors are commonly found in mammalian skin”,
describe how the DNA and protein (receptors) of this mole and other mammals could be
compared to show that they have a common ancestor
...
To carry out DNA comparison between different mammals enough DNA must be obtained
for analysis
...

o Reference to polymerase chain reaction/PCR
o Polymerase enzyme added
o Idea of need for primers and nucleotides
o 90-98oC, then 50-65 oC, then 70-75 oC
o Idea that cycle needs to be repeated several times/to make several copies of DNA
53
...

o Idea of comparing total number of bands
o Idea of comparing position of bands
o Idea of comparing size/width of bands
54
...
What is a nerve formed from?
o A nerve is formed of a bundle of many nerve fibres *the axon of the neuron), with
their myelin sheaths

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WBIO5/01 – Article potential questions

Biology A Level Tutor

56
...
What are sensory receptors?
o They transfer energy of a particular stimulus
o e
...
light, sound, movement
o into the electrochemical energy
o of an action potential in a sensory nerve fibre
58
...

o Exteroceptors – respond to external stimuli
o Interoceptor – respond to internal stimuli
o Chemoreceptors – Respond to chemical stimuli e
...
smell, taste, pH
o Proprioceptors – respond to changes in the position of the skeleton and the
degrees of muscle contraction
o Mechanoreceptors – respond to pressure, tension, movement
o Photoreceptors – respond to electromagnetic stimuli (for humans is visible light)
o Thermoreceptors – respond to heat stimuli
59
...
Discuss how regulatory authorities control the use of animals in research
...
Suggest why these regulating authorities should include people involved in animal research
and people not involved in animal research
...
Describe the ethical issues concerning the use of animals in research
...
Suggest two reasons why some people might have objections to the use of star-nosed moles
in this investigation
...
Scientist are encouraged to use non-animal alternatives in their research
...

o Tissue Culture/ Computer modelling
o More ethical/ no animals harmed
65
...
Suggest what is meant by the
term absolutism
...
There is an alternative to absolutism
...
Suggest the opinion a relativist would have with regard to using animals
in research
...


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WBIO5/01 – Article potential questions

Biology A Level Tutor

67
...

o Animal welfare (hygiene, veterinary care)
68
...

o Any population with a large gene pool has higher chances of survival, due to higher
chances of having an advantageous allele
...
g
...

o These individuals will survive, as they were better at exploring their environment
and finding prey
...
For natural selection to occur, there must be genetic variation within the population, so that
advantageous alleles can arise
...

70
...
Describe how scans
from magnetic resonance imaging (MRI) may be used to investigate the brain
...
How can you view and study differences in the brain? (Suggest how fMRI was able to show
that certain areas in the brain became more active when the star-nose mole uses the
appendages)
...
A CAT scan is the same as a CT scan
...
There are various ways of investigating organ structure and function
...

o Comparative image clarity (image resolution is higher for MRI)
o Thus, CT can only identify larger structures whereas MRI can identify smaller
structures
o Reference to tissue identified
o MRI uses radio waves and magnetic field whereas CT uses x-rays
o Both give 2D/3D images
o However, MRI is noisy and the patient needs to keep still and it is not good for
people with metal implants and pacemakers, whereas CT is using X-rays which is
not safe
o Images of both are at one point in time
o CT is cheaper than MRI
74
...

o Idea that fMRI can allow brain activity to be seen in real time
o Idea that fMRI uses radio waves/magnetic field
o Increase supply of oxygenated blood in active areas [active areas use more oxygen
thus more deoxygenated blood is produced]
o That reflects/does not absorb fMRI signals [if deoxygenated then more signal
absorbed]
o Idea of seen as a white area [area lights up or is a different colour]
o Idea of comparison with and without touching something by the appendages

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WBIO5/01 – Article potential questions

Biology A Level Tutor

75
...

o View brain activity directly
o Idea of see brain activity over a period of time
o Safer as does not use X-rays
o No need to use special dyes
76
...

o MRI gives better resolution
o Therefore, more detail can be seen
o No use of X-rays
o Therefore, safer/less risk of mutation
o Therefore, can be used more often
Paragraph: 6
Formidable = Inspiring fear
...

Haunts = A place frequented
...
The CNS consists of?
o The brain
o And the spinal cord
78
...

79
...
The
cerebral hemispheres have a number of functions
...

o Think, learn, feel emotions, personality, ability to see, memory, initiate motor
activity, speech, decision making, problem solving, intelligence, controls voluntary
behavior, forming associations, ability to carry out different movement
...
The mammalian processing centre is part of the cerebral hemispheres of the brain
...

81
...

o Any population with a large gene pool has higher chances of survival, due to higher
chances of having an advantageous allele
...
g
...

o These individuals will survive, as they were better at exploring their environment
and finding prey
...

o Thus, reproduce more
o Pass their advantageous allele to the next generation
o And over time (over several generations) the allele frequency within the population
will change (the frequency of the advantageous allele will increase)
Paragraph: 7
82
...
If each Eimer’s organ has a surface area of 1 cm2 what is the total area covered/explored in
one second and then calculate the total area for one minute?
o 12 cm2 covered in one second
o 720 cm2 covered in one minute

20

WBIO5/01 – Article potential questions

Biology A Level Tutor

Paragraph: 8
84
...

o Fovea which is one of the functional systems has only cone photoreceptors
o Cones are responsible for colour vision
o Cones function best in relatively bright light
o The rest of the retina is mostly covered by rod cells
o Rod cells are responsible for black and white vision
o The low-resolution area
o Work better in dim light
...
What is the retina?
o The light-sensitive tissue
o Lining the back of the eye
...
What is fovea?
o Located in the macula of the retina
o Provides the clearest vision of all
o Made out of cones, the cells that give the sharpest image
87
...

Describe how this is brought about
...

o ATPase activated to hydrolyse ATP ADP + Pi (with use of Ca+2) and energy used
to return myosin head to original position
...
Reticulum (and the muscle is relaxed)
...
What would be the role of calcium ions in this rapid eye movement
...

o (also needed by ATPase to work)
o Ca+2 in sarcoplasmic reticulum
89
...

o ATP needed to remove Ca+2 and return them to sarcoplasmic reticulum
o ATP needed to change shape of myosin in head
o And break the cross-bridges between actin and myosin (and return head to its
original position)
o (ATP also required for synthesis of neurotransmitters
...
What is saccades?
o A quick,
o Simultaneous movement
o Of both eyes
o In the same direction
o In order to focus an image on the fovea
91
...
For the retina to work, to be able to see, the visual cortex and ocular dominance must
develop
...
Paragraph 8 states “The much larger low-resolution area of your retina locates potentially
important areas to analyze next”, this lower resolution area is made up rod cells
...

o Light (energy) absorbed by rhodopsin / pigment
o Retinal changes shape / cis to trans
o Rhodopsin splits / bleaches
o Into retinal and opsin
o Sodium gates close / reduced permeability to sodium ions / less
sodium diffuses in / hyperpolarisation of membrane / rod cell
becomes more negative inside
o Bipolar cell becomes depolarised
o Action potential formed in ganglion (cell)
94
...

o One cone linked to one ganglion / bipolar cell
o One cone stimulated, one impulse to brain
o Several rods linked to one ganglion / bipolar cell convergence
o Several rods stimulated to trigger one nerve impulse
o Information from several rods is combined (summation)
Paragraph: 9
95
...

o Both have low and high-resolution areas
o The high-resolution areas have more sensitivity, sensory receptors
o For the eye is the fovea for the star is the 11th appendage
o Both focus on the area of interest for more information
o Fovea is located near the optic nerve and the 11th appendage near the mouth
o Both are focused due to rapid movements
96
...
How can muscles bring about this repositioning?
o The functional unit of contraction is the sarcomere
o Muscle cells contain many sarcomeres arranged in parallel
o The sarcomere contains overlapping actin and myosin
o The process by which actin is pulled in towards each other by the myosin is called
cross-bridge cycling
o This is how muscles contract
See questions in other sections of this report for muscle contraction
...
How is the retina connected with the brain?
o Cones and rods that make up the retina
o Synapse with bipolar neurones
o Which synapse with ganglion neurones
o Whose axons together make up the optic nerve
o The optic nerve connects to the brain
o Connect to the primary visual cortex where the information is processed
99
...
Describe how a neurotransmitter is released
from a brain cell when a signal arrives?
o Reference to arrival of impulse/action potential
o Calcium ion channels open in presynaptic membrane/brain cell membrane
o Calcium ions enter brain cells through diffusion down a concentration gradient
o Causing vesicles, containing neurotransmitters, to move towards/fuse with
presynaptic membrane
o Vesicles fuse with pre-synaptic membrane Or reference to exocytosis
o Neurotransmitter is released through exocytosis
100
...
This causes a neurotransmitter, such as acetylcholine, to be released
...

o Diffuses across gap
o Bind to receptors on post-synaptic membrane
o Idea of gated channels opening or sodium ions travel through post-synaptic
membrane
o Causing a depolarisation
o If sufficient present an action potential is set up in post-synaptic membrane
o Details such as temporal or spatial summation
24

WBIO5/01 – Article potential questions

Biology A Level Tutor

o
o
o
o

Idea that allows coordination/one-way flow of information
Idea that it allows integration in post-synaptic cell
Neurotransmitter broken down by enzyme
So that do not get prolonged action potential in post synaptic membrane (make
receptors available again)
o Credit reference to fate of products e
...
reabsorbed through pre-synaptic
membrane or to be re-synthesised into neurotransmitter substance
101
...

o Phospholipid bilayer
o Idea of its hydrophobic properties inhibit movement of ions across membrane
o Na+ gated channel present
o To allow Na+ to enter during depolarisation/to open when local currents occur
o K+ channels
o To allow K+ to diffuse
o Sodium-potassium pump
o To export Na+ /import K+
o Role of pump in neurone membrane
o Idea that only parts of the membrane may be involved e
...
nodes of Ranvier
(salutatory condition)
See questions given in other sections of this report
Paragraph: 11
102
...
List the different mammalian sensory systems
o Vision
o Hearing
o Touch
o Taste
o Smell
o Balance

25

WBIO5/01 – Article potential questions

Biology A Level Tutor

104
...
g
...
Why is the topographic organization important?
o Provides information about brain function
o And structure
106
...

o Different parts of the brain
o Represent information from different sensory receptors
o One region represents the stimuli received from the retina
o Another region represents the stimuli received from the ears
107
...
Paragraph 12 states “In all mammals, the left half of the body is represented predominantly
in the right side of the cortex, and vice versa”, why?
o There is criss-crossing of the neurones (wiring) in the spinal cord
o Due to anatomical (and physiological) constrains
109
...
What evidence are there that a critical ‘window’ exists
...
Is it nature or nurture responsible for the creation of this topographic organization?
o NURTURE has overriding influence
o on patterns laid down by nature
...
What are cell markers?
o Cell surface antigens
o That help identify and classify cells
o They are unique for different cell types
112
...

113
...
Explain the difference between spatial and temporal summation
...

o The total amount of neurotransmitter released may exceed the threshold value of
the postsynaptic neurone
o The higher the frequency of the action potential the more quickly the threshold
may be exceeded
114
...
Explain how nerve impulses are conducted along a myelinated axon after an action
potential has been initiated
...

o Reference to local currents
o Depolarisation of {adjacent / next} section of axon
o Sodium channels open / sodium ions move in (to axon)
o More
sodium
ions
move
in
so
more
sodium
channels
open / positive feedback idea
o Correct reference to +40 mV / {becomes positive / less negative}
inside the axon
o Potassium channels open / potassium ions move out (of the axon)
o Membrane repolarises
o Wave of depolarisation / depolarisation – repolarisation process
repeats itself along the axon
o Refractory period / hyperpolarised / more negative than resting potential
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WBIO5/01 – Article potential questions

Biology A Level Tutor

o Idea of impulse moves in one direction only
o Myelin sheath speeds up conduction
o Current jumps between nodes of Ranvier (saltatory effect)
116
...
Describe how propagation of a nerve impulse occurs along an axon
...
Explain how myelination increases the speed of nerve impulses in a neurone
...

o Impulse jumps from node to node (node of Ranvier)
119
...


28

WBIO5/01 – Article potential questions

Biology A Level Tutor

Paragraph: 13
120
...
g
...
Why is this (the 11th appendage) the most important part of the sensory surface?
o Because is responsible for sharp central awareness of the moles environment
o It is necessary in moles for activities where detail is of primary importance
o e
...
a prey is detected
122
...
fMRI scanning is another way of collecting information about the brain
...

o Increased neural activity of cerebrum when the 11th appendage is active
o More oxygen needed so increase in blood flow/oxyhaemoglobin in the region of
the brain associated with the 11th appendage
o Less radio waves/signal absorbed from that region
Paragraph: 14
Acuity = keenness
124
...
What is tactile stimulation?
o Tactile sensory stimulation involves the sensation of touch and texture
...
Why the one responds to tactile stimulation and the other to stimulation of larger areas
...

o There are more nerve fibres per Eimer organ leaving from the 11th appendage
o Than for other areas
o Thus, more information so tactile stimulation
o Or the are cortical area per nerve fibre is larger for the 11th appendage
127
...

o Method:
o Raise monkeys from birth in three groups for 6 months
o Group 1 are the control (no blindfold),
o Group 2 are blindfolded in both eyes,
o Group 3 are blindfolded in one eye (monocular deprivation)
o Then the tested the monkeys to see whether they can see using each eye
o Then tested the sensitivity of retinal cells
o Then tested the activity of nerves in the visual cortex in response to stimuli
o The results:
o Monkeys in Group 2 (both eyes blindfolded) had impaired vision
o Monkeys in Group 3 (monocular deprivation) were blind in the deprived eye
o Retinal cells were responsive in all groups
o Cortical activity was reduced in parts of the brain that process information
from the deprived eye
o Adults undergoing the same tests showed no difference between groups
...

o Conclusion:
o There is a critical window for visual neural development
o Which requires stimulus from the eye
Paragraph: 15
128
...
What does fovea mean in the context of this paragraph?
o High density of sensory receptors
o High number of nerve fibres connecting this region with the brain
o Large representation in the brain
30

WBIO5/01 – Article potential questions

Biology A Level Tutor

130
...

o Acoustic fovea is an area highly sensitive
o To a narrow range of frequency
o Detecting the frequency of the echo produced by the bat’s call
o Has a high number of neurons responding to the region of the acoustic fovea
o And it corresponds to a large section of the cortex
Paragraph: 16
131
...
Explain what is the doppler shift
...
Explain what is doppler shift compensation
...
Explain convergent evolution
o Phenotypic traits (observable characteristics)
o Are common between organisms sometimes
o Because they are adapted to similar conditions
o This is convergent evolution
o Where unrelated organisms evolve with a similar appearance
o As they adapt to the same conditions

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WBIO5/01 – Article potential questions

Biology A Level Tutor

135
...

o Where unrelated organisms evolve with a similar appearance
o As they adapt to the same conditions
136
...
“Why not just wire the entire sensory system for high resolution input and eliminate the
need to constantly shift the eyes, star or echolocation frequency?
o It would take a massive enlargement of the brain
o It would take a massive enlargement of the nerves carrying the sensory inputs
o It would flood the brain with unnecessary and overwhelming information
Paragraph:18
Staggering = Walk or move unsteadily, as if about to fall
...
Other examples of efficiency in design?
o Wrapping the DNA around histones
o Supercoiling DNA due to epigenetic markers
o DNA methylation and histone acetylation
o Thus, if this design did not exist and the DNA was stretched all the way out it would
be 2metres, but this way it is more efficient, as only the regions needed for
translation (to make proteins) are uncoiled and transcript
Paragraph: 19
Parcellation = the division into parcels, the act or process of dividing
139
...
How did Hubel and Weisel showed that the basic organisation of the visual cortex in
present at birth?
o Showed a critical window is present in the maturing of the visual cortex in cats
o They stitched one or both eyes of newly born kittens and monkeys and observed
the effect of this sensory deprivation
o One kitten eye stitched when it was 1 week old
...
How does the visual cortex develop?
o There appears to be further visual development after birth
o There is much overlap between the dentrites and synapses of axons in the different
columns in newly born mammals
o When an eye is stitched, the synapses from the closed eye are not working and
eventually are lost
o The axons and synapses of the active eye in the cortex become dominant
...
What does cortical parcellation mean?
o The division of the cortex in the brain into sections

Paragraph: 20
See questions given in other sections of this report in regard to animal ethics and welfare and on
the use of animals for research
...

See questions given in other sections of this report in regard to neurons, nerve fibers, sensory
neurons structure
...
Suggest how the scientists who conducted the study had their results accepted by other
scientists
o Idea of work appearing in a scientific journal or being presented at a conference
o Idea that validity or reliability is considered
o By another scientists/ref to peer review

33

WBIO5/01 – Article potential questions

Biology A Level Tutor

Paragraph: 21
144
...
What is a Stroke?
o The brain receives less/no blood supply
o Thus, no oxygen/glucose to the brain cells
o Brain cells become damaged or die
o Thus, rapid loss of brain function(s)
146
...
What factor increase the changes of a stroke?
o Factors that cannot be changed:
▪

Age

▪

Genes

▪

Gender

o Factors that can be changed:
▪

High blood pressure

▪

Obesity

▪

High cholesterol intake

▪

Higher saturated fat intake (low unsaturated fat intake)

▪

High salt intake
34

WBIO5/01 – Article potential questions

▪

Low fiber intake

▪

Smoking

▪

Inactivity

▪

Genetic inheritance

▪

High stress level

▪

High alcohol intake

Biology A Level Tutor

148
...
B
...
arrive at site of damage (macrophages)
o They accumulate cholesterol and other chemicals
...
B
...
and lipids clump together
and form fatty streaks
o More W
...
C
...
In studies concerning brain injuries, stroke what factors should be controlled?
o Age and gender
o Activity
o Lifestyle
o Diet
150
...

o Reliable/ representative data/study
o Because there is large variation between individuals
o To remove bias
o Accuracy /reliability
151
...

o To map the changes in the cortex
o To observe the small changes that will cause remapping of the cortex
152
...
What does experience-dependent plasticity mean?
o Cortical circuits and maps
o Can be modified
o By e
...
perceptual learning and visual deprivation (for the visual cortex)
Paragraph: 22
154
...
What is nature and what is nurture based on paragraph 22?
o Behaviours may shape the way the cortex is organized is Nurture
o Intrinsic developmental mechanisms may match the size of cortical maps to their behavioural significance is Nature
Paragraph: 23
See questions in other section of this report in regard to animal ethics and use of embryos for
experiments and research
...
Paragraph 23 states “sensory inputs from the star have an opportunity to influence the way
that the cortical maps form”, explain
...
Why are the hands of mole embryos gigantic?
o To dig
o To survive/ defend it self
o Needed for survival
Paragraph: 25
158
...
To write a proper reference for the study referred in this paragraph (25), what information
would you need?
o Authors’ names –Last name and Initial of first name –
o (date)
o article title
o journal title
o Vol
o (Issue)
o Pages
...
What possible theories are given here as an explanation of the 11th appendage’s cortical
map?
o Early development results in greater activity
o Early development results in more neurone signalling
o Thus, capture larger area in the brain
o Also, activity dependent expansion – i
...
the more it is used the more area it
acquires in the cortex
161
...
How do this cylinder looking appendages break free from the skin?
o Apoptosis of cells / cell suicide
o p53 is a gene that can initiate cell death
o Lysozymes – digestive enzymes are released
o Lysosome break in the cell, that release these enzymes and digest/break down the
cell
o Thus, the cells attaching the appendages die and the appendages break free from
the skin
163
...
Random mutation in the DNA that lead to errors in transcription occur often in all
organisms during the cell cycle
...
g
...
g
...
g
...
What does the S
...
townsendii the latin name of the Townsend’s
mole?
o Scapanus
o Has the same genus name with the coast mole
o As they have evolved from a common ancestor
o And they belong to the same species
166
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What does this name indicate? And why
is it used? (paragraph 28)
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167
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What does hypothesis mean?
o A proposed explanation
o Made on the basis of limited evidence
o As a starting point for further investigation
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WBIO5/01 – Article potential questions

Biology A Level Tutor

168
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o Causation: when a change in one variable is responsible for a change in another
variable
o Correlation: (relationship between two variables such that) a change in one of the
variables is reflected by a change in the other variable
169
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Define correlation?
o When a change in on variable is accompanied by a change in another variable
171
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Describe how the DNA and protein of these two moles could be compared to show that
they have a common ancestor
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To carry out DNA comparison between these moles enough DNA must be obtained for
analysis
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o Reference to polymerase chain reaction/PCR
o Polymerase enzyme added
o Idea of need for primers and nucleotides
o 90-98oC, then 50-65 oC, then 70-75 oC
o Idea that cycle needs to be repeated several times/to make several copies of DNA

40

WBIO5/01 – Article potential questions

Biology A Level Tutor

174
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o DNA profiling/fingerprinting/gel electrophoresis
175
...
This DNA was amplified,
fragmented and used to produce a DNA profile (DNA fingerprint) for each species
...

o Multiple copies of DNA made
o Using PCR (polymerase chain reaction)
o Credit any correct detail of PCR (step 1: 90 to 95oC, step 2: 50 to 65 oC, step 3: 70
to 80 oC, also use PCR mixture, i
...
primers/DNA polymerase/nucleotides, and
many repetitions – cycles)
o Reference to restriction enzymes/endonucleases to produce DNA fragments
o Idea of loading the DNA onto the gel (agarose gel)
o Idea that an electric current/charge is applied (potential difference)
o Reference to use of dye/fluorescent taq, UV light/southern blotting/gene
probes/radioactive labelling)
176
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o Idea of comparing total number of bands
o Idea of comparing position of bands
o Idea of comparing size/width of bands
177
...
e
...
Innate developmental mechanisms and behavioural patterns on the organization of the
cortex
...

o Innate mechanisms:
o Large collection of responses, usually seen in every member of a particular
species
o Not a learned behaviour
o Stimulus elicits the same response
o Which has been selected for over generations for survival purposes
o It is genetically determined (NATURE is completely dominant in the
development of neural pathways involved with such processes)
o Examples: avoidance reflexes, complex courtships, territorial displays
...
In young essential because they haven’t yet learnt
by trial-and-error, and in adults because they can leave higher areas
of brain free for more complex learned behaviour
...

o Learns from an experience - NURTURE
o Learning will vary from one organisms to the other
o (The ease with which learning takes place is at least partly due to genetics NATURE)
o Examples: habituation, learning, imprinting, exploratory (latent) learning
Paragraph: 29 and General Questions
179
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What is peer review and what are its benefits?
o The potential paper is send to other scientists (peers) to repeat the work
o To verify if it is valid, reliable
o If the results are significant
181
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Suggest two ways in which the results of these investigations can be shared or suggest how
scientists in other countries learnt of these findings
...
How to write a proper reference?
o Authors (Last name
...

o e
...
Catania K
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How can you improve the bibliography?
o More references
o Articles from scientific journals
o Websites
o Scientific books
185
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o The author of the page,
o The name of the website,
o The title of the article,
o The publication date,
o Example: e
...
"Last name, first name (or name of the website, if no author
available), "Title of article
...

186
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o Idea of work appearing in a scientific journal or being presented at a conference
o Idea that validity or reliability is considered
o By other scientists/reference to peer review
187
...
Explain what niche means using the star-nosed mole as an example
...

o The star-nosed mole lives in shallow tunnels
o The star-nosed mole eats earthworms
Questions on the images: Image page 3
189

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