Question 1

Sensory neurons are sometimes referred to as

Accepted Answer

A)  afferent neurons. 
B)  efferent neurons. 
C)  effectors. 
D)  affectors. 
E)  All options listed here are incorrect. 
A)  afferent neurons. 
B)  efferent neurons. 
C)  effectors. 
D)  affectors. 
E)  All options listed here are incorrect. A

Question 2

In a squid, which of the following behaviours would involve the highest degree of input from higher brain centres?

Accepted Answer

A)  The tentacles shoot forward to grasp a small fish and then withdraw it to the mouth. 
B)  An extended tentacle suddenly contracts in immediate response to a tactile stimulus. 
C)  The rate of the regular in and out movements of the mantle, that ventilate the gills, increases in response to a decrease in the oxygen concentration of the surrounding water. 
D)  A sudden forceful contraction of the mantle muscles expels water through the siphon, propelling the animal backwards, away from a predator. 
E)  The release of ink in response to fear. 
A)  The tentacles shoot forward to grasp a small fish and then withdraw it to the mouth. 
B)  An extended tentacle suddenly contracts in immediate response to a tactile stimulus. 
C)  The rate of the regular in and out movements of the mantle, that ventilate the gills, increases in response to a decrease in the oxygen concentration of the surrounding water. 
D)  A sudden forceful contraction of the mantle muscles expels water through the siphon, propelling the animal backwards, away from a predator. 
E)  The release of ink in response to fear. A

Question 3

The glial cells of the nervous system

Accepted Answer

A)  are electrically excitable. 
B)  provide electrical output to neurons. 
C)  are nourished by neurons. 
D)  provide electrical insulation. 
E)  receive input from the environment. 
A)  are electrically excitable. 
B)  provide electrical output to neurons. 
C)  are nourished by neurons. 
D)  provide electrical insulation. 
E)  receive input from the environment. D

Question 4

Which organism has the most complex neural circuitry?

Accepted Answer

A)  Drosophila melanogaster 
B)  Procambrus (crayfish) 
C)  Locusta (Orthopteran) 
D)  Mus musculus (mouse) 
E)  Helix (Gastropod) 
A)  Drosophila melanogaster 
B)  Procambrus (crayfish) 
C)  Locusta (Orthopteran) 
D)  Mus musculus (mouse) 
E)  Helix (Gastropod)

Question 5

The pigment-cup eye of a flatworm can

Accepted Answer

A)  recognise patterns. 
B)  form a clear image of an object. 
C)  focus light onto a layer of photopigment. 
D)  detect the direction of a light source. 
E)  form images that are subsequently combined physically. 
A)  recognise patterns. 
B)  form a clear image of an object. 
C)  focus light onto a layer of photopigment. 
D)  detect the direction of a light source. 
E)  form images that are subsequently combined physically.

Question 6

The speed of propagation of an action potential along an axon is increased by

Accepted Answer

A)  a decrease in the insulation of the axon. 
B)  an increase in the length of the axon. 
C)  an increase in the diameter of the axon. 
D)  the number of Na+ channels in the axon. 
E)  a decrease in the concentration of Na+ ions inside the axon. 
A)  a decrease in the insulation of the axon. 
B)  an increase in the length of the axon. 
C)  an increase in the diameter of the axon. 
D)  the number of Na+ channels in the axon. 
E)  a decrease in the concentration of Na+ ions inside the axon.

Question 7

What would happen to a neuron's electrochemical gradient if the plasma membrane became strongly permeable to Na+?

Accepted Answer

A)  The voltage difference across the neuronal membrane would decrease. 
B)  The voltage difference across the neuronal membrane would increase slightly. 
C)  The voltage difference across the neuronal membrane would be unchanged. 
D)  The voltage difference across the neuronal membrane would increase significantly. 
E)  The neuronal membrane would become unstably polarised. 
A)  The voltage difference across the neuronal membrane would decrease. 
B)  The voltage difference across the neuronal membrane would increase slightly. 
C)  The voltage difference across the neuronal membrane would be unchanged. 
D)  The voltage difference across the neuronal membrane would increase significantly. 
E)  The neuronal membrane would become unstably polarised.

Question 8

A drug that deactivates the potassium channels in the membrane of a neuron would

Accepted Answer

A)  make it easier to trigger action potentials in the neuron. 
B)  inhibit the conduction of action potentials along the neuron. 
C)  cause the membrane to hyperpolarise. 
D)  make it more difficult for the neuron to respond to repeated stimuli. 
E)  prevent depolarisation of the membrane. 
A)  make it easier to trigger action potentials in the neuron. 
B)  inhibit the conduction of action potentials along the neuron. 
C)  cause the membrane to hyperpolarise. 
D)  make it more difficult for the neuron to respond to repeated stimuli. 
E)  prevent depolarisation of the membrane.

Question 9

Sensory neurons are different from motor neurons in that

Accepted Answer

A)  sensory neurons carry information from enteroreceptors whereas motor neurons carry information from exteroreceptors. 
B)  motor neurons carry information away from the central nervous system whereas sensory neurons carry information towards the central nervous system. 
C)  sensory neurons function as efferent pathways whereas motor neurons function as afferent pathways. 
D)  motor neurons have long axons whereas the axons of sensory neurons are relatively short. 
E)  All the answers are correct. 
A)  sensory neurons carry information from enteroreceptors whereas motor neurons carry information from exteroreceptors. 
B)  motor neurons carry information away from the central nervous system whereas sensory neurons carry information towards the central nervous system. 
C)  sensory neurons function as efferent pathways whereas motor neurons function as afferent pathways. 
D)  motor neurons have long axons whereas the axons of sensory neurons are relatively short. 
E)  All the answers are correct.

Question 10

Which division of the nervous system can still function when all neural connections with the central nervous system are severed?

Accepted Answer

A)  Sympathetic nervous system. 
B)  Parasympathetic nervous system. 
C)  Enteric nervous system. 
D)  No division can function without the central nervous system. 
E)  Somatic nervous system. 
A)  Sympathetic nervous system. 
B)  Parasympathetic nervous system. 
C)  Enteric nervous system. 
D)  No division can function without the central nervous system. 
E)  Somatic nervous system.

Question 11

Which receptors have Pacinian corpuscles at the end of the sensory axon?

Accepted Answer

A)  Chemoreceptors 
B)  Mechanoreceptors 
C)  Photoreceptors 
D)  Enteroreceptors 
E)  Exteroreceptors 
A)  Chemoreceptors 
B)  Mechanoreceptors 
C)  Photoreceptors 
D)  Enteroreceptors 
E)  Exteroreceptors

Question 12

The following events occur at the membrane of a nerve cell during the generation of an action potential:
1) The potential inside the cell is positive.
2) The potential inside the cell is negative.
3) The threshold potential is reached.
4) Voltage-dependent K+ channels open.
5) Voltage-dependent Na+ channels open.
Which of the following is a correct sequence for these events?

Accepted Answer

A)  5, 1, 4, 2, 3. 
B)  2, 5, 4, 1, 3. 
C)  2, 5, 3, 4, 1. 
D)  2, 4, 5, 1, 3. 
E)  2, 3, 5, 1, 4. 
A)  5, 1, 4, 2, 3. 
B)  2, 5, 4, 1, 3. 
C)  2, 5, 3, 4, 1. 
D)  2, 4, 5, 1, 3. 
E)  2, 3, 5, 1, 4.

Question 13

Motor neurons

Accepted Answer

A)  detect signals from the external environment. 
B)  monitor blood pressure. 
C)  receive information from muscle cells to initiate a response. 
D)  control the activity of several glands. 
E)  require enteroreceptors and exteroreceptors for function. 
A)  detect signals from the external environment. 
B)  monitor blood pressure. 
C)  receive information from muscle cells to initiate a response. 
D)  control the activity of several glands. 
E)  require enteroreceptors and exteroreceptors for function.

Question 14

When pain is felt, it is thought that nerve endings are stimulated by

Accepted Answer

A)  activation of stretch receptors. 
B)  the deformation of Pacinian corpuscles. 
C)  adrenaline released in response to the damage. 
D)  chemicals released by damaged or irritated tissue. 
E)  the release of endorphins. 
A)  activation of stretch receptors. 
B)  the deformation of Pacinian corpuscles. 
C)  adrenaline released in response to the damage. 
D)  chemicals released by damaged or irritated tissue. 
E)  the release of endorphins.

Question 15

Which of the following is NOT found in the central grey region of the spinal cord?

Accepted Answer

A)  Nerve cell bodies 
B)  Dendrites 
C)  Initial parts of axons and synaptic inputs 
D)  Areas of sensory connections 
E)  Axons that pass up and down the cord 
A)  Nerve cell bodies 
B)  Dendrites 
C)  Initial parts of axons and synaptic inputs 
D)  Areas of sensory connections 
E)  Axons that pass up and down the cord

Question 16

Energy in the form of ATP is required

Accepted Answer

A)  to generate an action potential. 
B)  to propagate an action potential. 
C)  to maintain a nerve cell membrane at resting potential. 
D)  to transport K+ out of the cell. 
E)  All of the answers are correct. 
A)  to generate an action potential. 
B)  to propagate an action potential. 
C)  to maintain a nerve cell membrane at resting potential. 
D)  to transport K+ out of the cell. 
E)  All of the answers are correct.

Question 17

Many autonomic pathways are tonically active, which means

Accepted Answer

A)  animals have strong avoidance behaviour to painful stimuli. 
B)  special neural networks control the automatic function of many internal organs. 
C)  the complex reflex circuits of the enteric nervous system is embedded in the walls of the digestive system. 
D)  that some groups of autonomic neurons fire action potentials continually and so control the level of activity of the organ they innervate. 
E)  autonomic neurons have axons which project to peripheral ganglia to control activity. 
A)  animals have strong avoidance behaviour to painful stimuli. 
B)  special neural networks control the automatic function of many internal organs. 
C)  the complex reflex circuits of the enteric nervous system is embedded in the walls of the digestive system. 
D)  that some groups of autonomic neurons fire action potentials continually and so control the level of activity of the organ they innervate. 
E)  autonomic neurons have axons which project to peripheral ganglia to control activity.

Question 18

Mechanical stimulation of a Mauthner neuron, in fish, results in a stereotyped escape response. Within milliseconds, contraction of particular trunk muscles and other muscles in the fin, jaw and operculum, cause an abrupt body turn away from the stimulus, positioning the fish to accelerate away. This behaviour is an example of a

Accepted Answer

A)  rhythmically generated pattern modified by conscious input. 
B)  consciously generated pattern modified by a rhythmic pattern generator. 
C)  monosynaptic reflex. 
D)  polysynaptic reflex. 
E)  response to adrenaline release. 
A)  rhythmically generated pattern modified by conscious input. 
B)  consciously generated pattern modified by a rhythmic pattern generator. 
C)  monosynaptic reflex. 
D)  polysynaptic reflex. 
E)  response to adrenaline release.

Question 19

The cerebral cortex is concerned with

Accepted Answer

A)  the processing of sensory information. 
B)  the control of movement. 
C)  memory. 
D)  emotional responses. 
E)  All of these functions. 
A)  the processing of sensory information. 
B)  the control of movement. 
C)  memory. 
D)  emotional responses. 
E)  All of these functions.

Question 20

What is the factor in the evolution of neuronal membranes that limits the physical distance over which electrical information integration can occur?

Accepted Answer

A)  Cranio-electroconductivity 
B)  The hormonal output of neurons. 
C)  The energy level of the neuronal electrochemical gradient 
D)  The electrical properties of neuronal membranes 
E)  The distance of environmental input signalling from external receptors 
A)  Cranio-electroconductivity 
B)  The hormonal output of neurons. 
C)  The energy level of the neuronal electrochemical gradient 
D)  The electrical properties of neuronal membranes 
E)  The distance of environmental input signalling from external receptors

Exam 29: Nervous Systems

Sensory neurons are sometimes referred to as

In a squid, which of the following behaviours would involve the highest degree of input from higher brain centres?

The glial cells of the nervous system

Which organism has the most complex neural circuitry?

The pigment-cup eye of a flatworm can

The speed of propagation of an action potential along an axon is increased by

What would happen to a neuron's electrochemical gradient if the plasma membrane became strongly permeable to Na+?

A drug that deactivates the potassium channels in the membrane of a neuron would

Sensory neurons are different from motor neurons in that

Which division of the nervous system can still function when all neural connections with the central nervous system are severed?

Which receptors have Pacinian corpuscles at the end of the sensory axon?

Motor neurons

When pain is felt, it is thought that nerve endings are stimulated by

Which of the following is NOT found in the central grey region of the spinal cord?

Energy in the form of ATP is required

Many autonomic pathways are tonically active, which means

The cerebral cortex is concerned with

What is the factor in the evolution of neuronal membranes that limits the physical distance over which electrical information integration can occur?

Nature of Molecules

Biomolecules

The Chemistry of Life

Functioning Cells

Movement Across Membranes

Harvesting Energy

Cells, Tissues and Signals

Cell Division

Inheritance

Genes, Chromosomes and Dna

The Genetic Code

Gene Expression

Genomes, Mutation and Cancer

Viruses

Genetic Engineering and Biotechnology

Reproduction, Growth and Development of Flowering Plants

Structure of Plants

Plant Nutrition, Transport and Adaptation to Stress

Plant Hormones and Growth Responses

Animal Reproduction

Animal Development

Homeostasis: Water, Solutes and Excretion

Gas Exchange in Animals

Circulation

Metabolism, Temperature Regulation and Environmental Stress

Animal and Human Nutrition

Innate Defences and the Immune System

Hormonal Control in Animals

Animal Movement

Animal Behaviour

Evolving Life

Evolving Earth

Mechanisms of Evolution

Bacteria

The Protists

Plants

Fungi

Simple Animals: Sponges to Flatworms

Annelids, Molluscs, Nematodes and Arthropods

Echinoderms and Chordates

Australian Biota

Population Ecology

Living in Communities

Ecosystems

Human Impacts

Filters

What would happen to a neuron's electrochemical gradient if the plasma membrane became strongly permeable to Na⁺?