BIOLOGY CLASS TEST 1 MEMO 2017

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LIFE SCIENCE 3B FET
CLASS TEST 1 - 2017
SURNAME: ___________memo_____________________________ STUDENT NR. __________
QUESTION 1 [25]
Choose the alternative that best answers the question or completes the statement. Only encircle the correct letter.
1.1 If a stimulus is to be perceived by the nervous system, which part of the sensory pathway must occur first?
A) Integration
B) Transmission
C) Transduction
D) Reception
E) Amplification
1.2 Cerebrospinal fluid can bedescribed as all of the followingexcept______
A) functioningin transportof nutrients and hormones through the brain.
B) a product of the filtration of blood by the brain.
C) formed from layers of connective tissue.
D) functioningto cushion the brain.
E) fillingcavities in thebrain called ventricles.
1.3 Which of the followingactivities would beassociated with the parasympathetic division of the nervous system?
A) Rest and digestion
B) Release of both acetylcholineand epinephrine
C) Increased metabolic rate
D) Fight-or-flightresponse
E) Releaseof epinephrineonly
1.4 Which area of the brain is mostintimately associated with the unconscious control of respiration and circulation?
A) Thalamus
B) Cerebellum
C) Medulla oblongata
D) Corpus callosum
E) Cerebrum
1.5 Integration of simpleresponses to certain stimuli,such as the patellar reflex,is accomplished by which of the following?

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A) Spinal cord
B) Hypothalamus
C) Corpus callosum
D) Cerebellum
E) Medulla
1.6 Which partof the vertebrate nervous system is most involved in preparation for the fight-or-flightresponse?
A) Sympathetic
B) Somatic
C) Central
D) Visceral
E) Parasympathetic
1.7 Which system controls smooth and cardiac muscles of the digestive, cardiovascular,and excretory systems?
A) Central nervous system
B) Peripheral nervous system
C) Autonomic nervous system
D) Parasympathetic nervous system
E) Sympathetic nervous system
1.8 Which of the followingis (are) characteristic of a simplenervous system?
A) A nerve net such as is found in cnidarians
B) Nerve cell ganglia
C) Havingelectrical impulsestravelingin both directions
D) both A and C
E) A, B and C
1.9 An organismthatlacks integration centres __________
A) cannotreceive stimuli.
B) will not have a nervous system.
C) will not be able to interpret stimuli.
D) can be expected to lack myelinated neurons.
E) only have bipolar neurons.
1.10 The divisionsof the nervous system that have antagonistic actions,or opposingactions are________________
A) motor and sensory.

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B) sympathetic and parasympathetic.
C) presynaptic and postsynaptic.
D) forebrain and hindbrain.
E) central nervous system and peripheral nervous system.
1.11 In the vertebrate brain and spinal cord there are several types of glial cells in which system?
A) Central nervous system
B) Peripheral nervous system
C) Autonomic nervous system
D) Parasympathetic nervous system
E) Sympathetic nervous system
1.12 If you were writingan essay,which partof the brain would be most active?
A) Temporal and frontal lobes
B) Parietal lobe
C) Broca's area
D) Wernicke's area
E) Occipital lobe
1.13 Most of the neurons in the human brain are
A) sensory neurons.
B) motor neurons.
C) interneurons.
D) auditory neurons.
E) olfactory neurons.
1.14 Most of the organelles in a neuron are located in the
A) dendritic region.
B) axon hillock.
C) axon.
D) cell body.
E) axon terminals.
1.15 In certain largeanimals,this typeof neuron can extend beyond one meter in length
A) glial cell in thebrain.
B) a sensory neuron.

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C) an interneuron.
D) a glial cell ata ganglion.
E) a neuron that controls eye movements.
1.16 The "threshold" potential of a membrane
A) is the point of separation froma livingfroma dead neuron.
B) is the lowest frequency of action potentials a neuron can produce.
C) is the minimum hyperpolarization needed to prevent the occurrenceof action potentials.
D) is the minimum depolarization needed to operate the voltage-gated sodium and potassium channels.
E) is the peak amount of depolarization seen in an action potential.
1.17 Action potentials move along axons
A) more slowly in axons of largethan in small diameter.
B) by the directaction of acetylcholineon the axonal membrane.
C) by activatingthe sodium-potassium"pump" at each point alongthe axonal membrane.
D) more rapidly in myelinated than in non-myelinated axons.
E) by reversingthe concentration gradients for sodiumand potassiumions.
1.18 Saltatory conduction is a term applied to conduction of impulses
A) across electrical synapses.
B) an action potential that skips the axon hillock in moving fromthe dendritic region to the axon terminal.
C) rapid movement of an action potential reverberating back and forth alonga neuron.
D) jumpingfrom one neuron to an adjacentneuron.
E) jumping from one node of Ranvier to the next in a myelinated neuron.
1.19 The surfaceon a neuron that discharges synaptic vesiclesis the
A) dendrite.
B) axon hillock.
C) node of Ranvier.
D) postsynaptic membrane.
E) presynaptic membrane.
1.20 Neural transmission across a mammalian synaptic gap is accomplished by
A) the movement of sodiumand potassiumions fromthe presynaptic into the postsynaptic neuron.
B) impulses travelingas electrical currents acrossthegap.
C) impulses causing the release of a chemical signal and its diffusion across the gap.

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D) impulses ricochetingback and forth across the gap.
E) the movement of calciumions fromthe presynaptic into the postsynaptic neuron.
1.21 The activity of acetylcholinein a synapseis terminated by
A) its activetransportacross thepresynaptic membrane.
B) its diffusion acrossthepresynaptic membrane.
C) its activetransportacross thepostsynaptic membrane.
D) its diffusion acrossthepostsynaptic membrane.
E) its degradation by a hydrolytic enzyme on the postsynaptic membrane.
1.22 Where are neurotransmitter receptors located?
A) on the nuclear membrane
B) at nodes of Ranvier
C) on the postsynaptic membrane
D) on the membranes of synaptic vesicles
E) in the myelin sheath
1.23 The divisionsof the nervous system that have antagonistic actions,or opposingactions are ________________
A) motor and sensory.
B) sympathetic and parasympathetic.
C) presynaptic and postsynaptic.
D) forebrain and hindbrain.
1.24 Which area of the brain is mostintimately associated with the unconscious control of respiration and c irculation?
A) thalamus
B) cerebellum
C) medulla oblongata
D) cerebrum
1.25 Which of the followingcontains regions thathelp regulate hunger and thirst?
A) cerebrum
B) cerebellum
C) thalamus
D) hypothalamus

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QUESTION 2 [14]
Give the correct biological term for each of the following statements or definitions.
2.1 The neurotransmitter responsiblefor thermoregulation. Serotonin
2.2 The diseasecaused by the formation of neurofibrillary tangles and amyloid plaquesin the brain. Alzheimer’s disease
2.3 The element needed for the production of thyroxin. Iodine
2.4 The terminal part of the spinal cord. conus medullaris
2.5 Open spacebetween the axon of one neuron and the dendrite of the followingneuron. Synapse
2.6 The clusteringof sensory organs at the front end of the body. Cephalization
2.7 The reflex centre which controls the blood pressurein humans. Vasomotor centre
2.8 The two (2) centres which form part of the Pons and assistto regulate breathing.(2) Pneumotaxic- and Apneustic
centers
2.9 The pathway of which the activity is enhanced by addictivedrugs. Dopamine
2.10 The neurotransmitter activewhen you wake up in the morning. Norepinephrine
2.11 Cells which supply supportand nourishmentto neurons. Neuroglia
2.12 The number of spinal nerves found in the human nervous system. 31 pairs
2.13 A thick band of axons connectingthe two (2) cerebral hemispheres. Corpus callosum
QUESTION 3 [42]
3.1 The Beast played rugby for the Sharks on the 10th of January 2012,he stepped onto a bigthorn which was lyingon the
rugby field,he immediately fell down lifthis foot and a few seconds later started cryinglikea baby.Draw and label a
detailed diagramto explain the stimulus sensed and impulses send through his spinal cord. (20 x ½ = 10)

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3.2 Discuss thedepolarization and repolarization of an impulseacrossan axon,from a restingpotential to an action
potential. (10)
o When an axon is not conducting an impulse the membrane potential is -65mV
o This indicates that the inside of the axon is more negative [more K-ions and less Na+ ions]
o than the outside [less K-ions and more Na+ ions])
o The Action potential is
o a rapid change in polarity across a part of the axon membrane as the nerve impulse occurs.
o It uses gated channel proteins in axon membrane to exchange Na+ and K- ions.
o When the Na+ gates open and Na+ moves inside the axon, depolarization take place.
o The action potential changes from -65mV to +40mV.
o The Na+ gates close and K- gates open and K- leave the axon
o Action potential change from +40mV to -65mV, repolarization occurred
3.3 Name and distinguish between the two (2) types of depression found in humans. (4)
 In major depressive disorder(1), patients have a persistent lack of interest or pleasure in most activities (1)
 Bipolar disorder(1) is characterized by manic (high-mood)(½) and depressive (low-mood) phases(½)
3.4 Name two (2) drugs used to treat depression in humans. (2)
Prozac and Lithium
3.5 Briefly describewhat neuromodulators are and give one example of a neuromodulator. (3)
Neuromodulators: Block the release of neurotransmitters (1) or modify a neuron’s response to a neurotransmitter.
(1)
E.g. endorphins.(1)
3.6 Explain the chemical transmission of an impulseacrossa synapse. (11)
o It is carried out by means of neurotransmitters, found in synaptic vesicles.
o Nerve impulses reaches the axon terminal/synaptic endplate
o Gated channels for Ca+ open and it entersthe neuron.
o The rise in Ca+ stimulates synaptic vesicles to merge with the presynaptic membrane.
o Neurotransmitter molecules are released into synaptic cleft.
o They diffuse through to the postsynaptic membrane.
o Where they bind with specific receptor proteins.
o Sodium (Na) diffuses in o the dendrite terminal and an action potential begins.
3.7 What arethe folds and grooves of the cerebral cortex called? (2)
Sulci and gyri
QUESTION 4 [14]
Fit column B with column A.
Column A Column B Answer
4.1 Vasomotor centre A. Central pattern generators. G
4.2 Hypothalamus B. Apneustic centers N
4.3 Thalamus C. Develop into 3 regions E

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4.4 Epithalamus D. Vermis M
4.5 Diencephalon E. Control emotions C
4.6 Cerebrospinal fluid F. Corpus callosum K
4.7 Cerebullum G. Regulated blood vessel diameter D
4.8 Cerebrum H. Outer protective membrane F
4.9 Pons I. Annelids and arthropods B
4.10. Pia mater J. Flatworms L
4.11 Dura mater K. Cushion or shock absorbs ion H
4.12 Spinal cord L. Inner protective membrane A
4.13 Clusters of neurons M. Includes the pineal gland I
4.14 Central nervous system N. Controls thirst J
Total : 95