Back to Revision NotesQ1.
Book 2 Chapters 2 & 3
Essay structure: 4 marks
Content: synaptic potential - small, graded, decays with distance,
depends on receptor gated or second messenger channels, can summate. Action
potential - relatively large, fixed amplitude, all or nothing, does not
decay with distance, depends on voltage gated channels.
When sufficient receptor potentials are summated to depolarise the
axon hillock to threshold, voltage gated sodium channels open allowing
sodium influx. As membrane potential becomes positive, these channels close
and voltage gated potassium channels open allowing efflux of potassium.
This re-polarises the membrane. Potassium channels are open slightly longer
than sodium channels causing the hyperpolarisation following the repolarisation.
12
marks
Understanding e.g. that different channels occur at different
places in the cell membrane 4 marks
Book 1 Chapter 4
Structure: 4 marks
Content:
Ann's fitness: is relative to other members of the population,
should not be based on one component of fitness, should reflect lifetime
reproductive success up to 6 marks
Study of fitness: requires information on survival and reproduction
of offspring, not just those of Ann but of other female tits in the population.
This information must be gathered for the lifetime of all females reproducing
during Ann's lifetime up to 6 marks
Understanding: 4 marks
Book 1 Chapter 4,5,9,10; Book 3 Chapter 2; Book 4 Chapter 4
There are three main reasons:
1) survival - there is a struggle for existence and only some survive
[Bk. 1: 4.3.1, 4.3.2]
2) developmental factors (e.g. caste - ants [Bk. 4: 4.3.1], mole rats
[Bk. 1:10.4.1]; song - zebra finches [Bk. 1: 5.6]; hormones - rats [Bk.
1: 5.3.1]; people (infertility) [Bk. 4: 4.5.5] )
3) mate choice (e.g. finding a mate, being chosen by a mate - territories-/displays;
competitors (red deer [Bk. 1: 4.3.8], fish/birds [Bk. 1: 9.4], frogs [Bk.
3: 2.2.5-2.2.8] )
Structure: 4 marks
Conent:
Survival 4 marks
Development 4 marks
Mate choice 4 marks
An additional 4 marks could be gained by expanding the survival/development/mate
choice sections. (up to max. of 12)
Understanding: 4 marks
Book 3 Chapter 5
Structure: 4 marks
Content:
Structurally there could be an absence of nociceptors and associated
C fibres, no T cells feeding into the spinothalamic tract, no receptors
for substance P, an excess of opiate receptors. 6 marks
Functionally there could be overactivity in the large diameter afferent
fibres, overactivity in the interneurons in the substantia nigra, overactivity
in the descending pathway (all closing the gate), overproduction and leakage
of opioids 6 marks
Understanding: 4 marks
Book 1 Chapter 8 & 10; Book 3 Chapter 1 & 2; Book 5 Chapter
4
Structure: 4 marks
Content:
Some discussion that communication is the exchange of information reducing
uncertainty; that "eavesdropping" complicates any definition; that many
species specific signals have evolved for intraspecific communication;
that it can involve any of the senses. 6 marks
Examples of the link between communication and specific behaviour -
e.g. finding a mate; choosing a mate; direct competition (for territory/food/mates)
especially between males; parental behaviour; group living (dominance/vigilance);
eavesdropping and prey capture etc. Examples should be varied as to behaviour
and sensory modality. 6 marks
Understanding: 4 marks
Book 2 Chapter 10, 11; Book 4 Chapter 5; Book 6 Chapter 3
Structure: 4 marks
Content:
Psychological: different classifications (episodic/declarative/working/short
term etc.), unique, instantaneous (e.g. episodic); crucial to personality
(cf Alzheimer's). 6 marks
Neurophysiological: requires neural substrate (e.g. modified synapses/firing
characteristics); specific memories are associated with firing of specific
cells (e.g. place cells/Penfield) involves the hippocampus and temporal
lobes; disrupted by trauma/lesion/stroke. 6 marks
Understanding: 4 marks
Memory formation could possibly be included, but by itself would not
make for a good answer.
Book 1 Chapter 7; Book 5 Chapter 2
Homeostasis is the maintenance of a stable internal environment. Homeostasis
is the mechanism by which the levels of various substances (e.g. nutrients/water/oxygen)
in the body are maintained despite continuous depletion (because the body
uses them). In addition external factors (sunshine/stressors) can give
rise to internal changes (e.g. in temperature and hormone levels). These
internal and external factors contribute to and result in motivation which
is associated with variability in behaviour; goal-directed behaviour; a
common currency; selectively potentiating species typical behaviour. The
resultant behaviour is such as to remove external factors and/or restore
internal variables to appropriate levels. Hence some behaviour, but not
all (e.g. exploration, sex), is also part of the homeostatic mechanism.
Homeostasis: 4 marks
Motivation: 8 marks
Behaviour: 6 marks (examples)
Understanding: 2 marks
Book 1 Chapter 5; Book 4 Chapter 4
Structure: 4 marks
Content: up to 6 marks for any appropriate, well explained
example to a maximum of 12 marks
bird song: in the zebra finch neural substrate (HVc/RA) no differences
at hatching; oestrogen "organises" these areas; testosterone "activates"
these areas; nestlings must hear the song of adults during memorisaton
phase; fledglings must hear their own song during motor phase.
rodent sexual behaviour: neonatal testosterone organises and
pubertal testosterone activates sexual behaviour; female or male sexual
behaviour results from relevent testosterone levels irrespective of the
sex of the subject; testosterone sustains the LA/BC muscles (involved in
penile reflexes) which in turn sustains the spinal nucleus bulbocavernosus;
there are clearly identifiable sensitive periods.
ocular occlusion: there is a sensitive period for the formation
of appropriate connections within the visual system; during this time the
connections are affected by stimulation; after this time they are not.
sphynx moth antennae: the genotype influences whether long sense
organs are found on the antennae; if they are found then they influence
the antennal lobes to grow macroglomerular complexes
castes: permanent morphological changes result from different
environmental circumstances during development; e.g. soldier vs worker
ants; queen vs worker bees. The same genotype can give rise to very different
phenotypes.
Understanding: 4 marks
Book 6 Chapters 1, 7 & 8
Structure: 4 marks
Content: Students should attempt to clarify the distinction
between neurological (or organic) disorders and psychiatric (psychological
or functional) disorders by giving examples (e.g. Parkinson's, stroke and
depression, schizophrenia respectively). The implication of this mind/brain
dichotomy for explanations and for treatment should be explored. Social
and life-history explanations may result in different treatment from biological
explanations. But if all are susceptible to treatment with drugs perhaps
they are all organic? 12 marks
Understanding: 4 marks
| Back to Questions |
Back to Revision Notes |