Ch20 Invertebrate Sensorimotor Behavior Full Test Bank

Chapter 20: Walking, Flying, and Swimming: Cellular Mechanisms of Sensorimotor Behavior in Invertebrates

Test Bank

Type: multiple choice question

Title: Chapter 20 Question 01

1. Which of these is not an advantage to the use of invertebrates to study the neural basis of behavior?

Feedback: Subhead: From Behavior to Neurons and Vice Versa

Learning Objective: List three advantages that invertebrates offer for studying how nerve cells integrate information to produce coordinated behavior.

Bloom’s Level: 1. Remembering

a. Invertebrate behavior tends to be more consistent and replicable than that of most vertebrates.

b. The nervous system of many invertebrates is easier to access or observe than that of most vertebrates.

c. Behavioral functions are often controlled by a smaller number of neurons in invertebrates than in vertebrates.

d. The invertebrate brain has basically the same structure as that of vertebrates, but with fewer neurons.

e. All of the above are advantages of invertebrates.

Type: multiple choice question

Title: Chapter 20 Question 02

2. Which of the species below is studied because its relatively simple behaviors are controlled by a small number of easily observable, large neurons?

Feedback: Subhead: From Behavior to Neurons and Vice Versa

Learning Objective: List three advantages that invertebrates offer for studying how nerve cells integrate information to produce coordinated behavior.

Bloom’s Level: 2. Understanding

a. Leech

b. Honeybee

c. Cockroach

d. Desert ant

e. Giant squid

Type: multiple choice question

Title: Chapter 20 Question 03

3. The desert ant Cataglyphis bicolor uses this as a primary stimulus for navigating back to its nest after a foraging trip.

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Describe four different sensory systems that ants and bees use to navigate.

Bloom’s Level: 1. Remembering

a. Pheromone trail

b. Visual landmarks

c. Polarized light

d. Directional cues from the stars

e. The odor of the nest

Type: multiple choice question

Title: Chapter 20 Question 04

4. The foraging trajectory of the desert ant Cataglyphis bicolor follows

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Describe four different sensory systems that ants and bees use to navigate.

Bloom’s Level: 1. Remembering

a. a winding, meandering outward path, with a direct and rapid return.

b. a direct and rapid outward path, and a winding, meandering return.

c. a direct rapid outward and homeward path.

d. a path in the shape of a spiral or concentric circle.

e. short segments between one spatial landmark and the next.

Type: multiple choice question

Title: Chapter 20 Question 05

5. The text discusses the use of these navigational cues by honeybees.

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Describe four different sensory systems that ants and bees use to navigate.

Bloom’s Level: 1. Remembering

a. Geomagnetic cues, polarized light, and a visual odometer

b. Olfactory cues, wind direction, and sun location

c. Wind direction, polarized light, and internal pedometer

d. Auditory cues from the hive, pheromones, and geomagnetic cues

e. Pheromones, sun location, and wind direction

Type: multiple choice question

Title: Chapter 20 Question 06

6. Imagine that a researcher sets up a tunnel through which a bee needs to fly in order to find a sucrose feeder. The inside of the tunnel is lined with a two-inch square black-and-white checker pattern. After the bee is accustomed to foraging here, the researchers do a test in which the tunnel is lined with an (otherwise identical) three-inch square black-and-white checker pattern, and the feeder is removed. Based on what you know about honeybee navigation, predict how the bee will likely behave.

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Describe four different sensory systems that ants and bees use to navigate.

Bloom’s Level: 4. Analyzing

a. It will search for food closer to the hive than the location of the original feeder.

b. It will search for food farther from the hive than the location of the original feeder.

c. It will search for food at approximately the distance of the location of the original feeder.

d. It will just keep flying through the tunnel without searching for food.

e. It will remain at the hive due to the unfamiliar stimulus.

Type: multiple choice question

Title: Chapter 20 Question 07

7. If a foraging bee is placed under a device that modifies the ambient magnetic cues, and the bee tries to orient to the south, the bee will

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Describe four different sensory systems that ants and bees use to navigate.

Bloom’s Level: 2. Understanding

a. orient to the true south.

b. orient randomly.

c. orient to the modified magnetic south.

d. orient to the true south only if the sun is out.

e. fly in circles until it gets out from under the device.

Type: multiple choice question

Title: Chapter 20 Question 08

8. Ants are able to use the sun for navigation, despite its movement through the sky, by

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Describe four different sensory systems that ants and bees use to navigate.

Bloom’s Level: 2. Understanding

a. using time of day to correct for the trajectory of the sun.

b. only traveling at the same time each day, to keep the sun consistent.

c. always orienting away from the sun for an outward trip, and toward the sun to get home.

d. using specialized ommatidia that orient toward the sun at all times.

e. foraging to the east in the morning, and to the west in the afternoons.

Type: multiple choice question

Title: Chapter 20 Question 09

9. How do foraging desert ants use landmarks or distinctive features of the terrain?

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Describe four different sensory systems that ants and bees use to navigate.

Bloom’s Level: 2. Understanding

a. To mark and remember the “goal” location where food can be found

b. Primarily near the nest to pinpoint the location of the hole

c. Throughout the foraging trip as one of the primary navigational cues

d. As “sign posts” to mark where the path needs to turn or change

e. Not at all, because they are insensitive to landmark cues

Type: multiple choice question

Title: Chapter 20 Question 10

10. In addition to using polarized light to navigate, Cataglyphis can also use the following cues

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Describe four different sensory systems that ants and bees use to navigate.

Bloom’s Level: 1. Remembering

a. Pedometer, pheromone trails, and star compass

b. Wind direction, terrain landmarks, and pheromone trails

c. Pedometer, wind direction, and sun location

d. Pheromone trails, geomagnetic field, and sun location

e. Star compass, geomagnetic field, and wind direction

Type: multiple choice question

Title: Chapter 20 Question 11

11. If a researcher were to place a dome over a navigating desert ant that filters polarized light as it travels, she would expect to see

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Explain how polarized light provides a navigation compass for many invertebrates.

Bloom’s Level: 3. Applying

a. a disrupted outward path, and no attempt to return home.

b. a normal outward path, but disruption in the homeward path.

c. normal navigation on both the outward and homeward path.

d. random wandering around the nest with no attempt to forage.

e. a longer outward trip than usual, and failure to compensate on the homeward path.

Type: multiple choice question

Title: Chapter 20 Question 12

12. If researchers were to place a frosted glass dome over a navigating desert ant that allowed light to pass through but prevented the ants from seeing the sun in the sky, they would expect to observe in the ants

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Explain how polarized light provides a navigation compass for many invertebrates.

Bloom’s Level: 3. Applying

a. a disrupted outward path and no attempt to return home.

b. a normal outward path but disruption in the homeward path.

c. normal navigation on both the outward and homeward path.

d. random wandering around the nest with no attempt to forage.

e. a longer outward trip than usual and failure to compensate on the homeward path.

Type: multiple choice question

Title: Chapter 20 Question 13

13. The sensitivity of an ant’s visual system to the polarization of light is based on

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Explain how specialized ommatidia allow the insect eye to respond preferentially to polarized light.

Bloom’s Level: 2. Understanding

a. stacks of microvilli with specific orientations.

b. ommatidia that face different directions.

c. two distinct photopigments that are sensitive to light polarized at different angles.

d. the fact that UV light looks different when it is polarized at different angles.

e. special cells that act as filters over some photoreceptors, blocking light polarized at specific angles.

Type: multiple choice question

Title: Chapter 20 Question 14

14. The location of the ant eye most sensitive to polarized light is the

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Explain how specialized ommatidia allow the insect eye to respond preferentially to polarized light.

Bloom’s Level: 1. Remembering

a. center.

b. caudal region.

c. ventral edge.

d. dorsal rim.

e. frontal segment.

Type: multiple choice question

Title: Chapter 20 Question 15

15. If researchers were to damage the dorsal rim of the eyes of the desert ant, then observe its foraging behavior, they might expect to observe

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Explain how specialized ommatidia allow the insect eye to respond preferentially to polarized light.

Bloom’s Level: 3. Applying

a. a disrupted outward path and no attempt to return home.

b. a normal outward path but disruption in the homeward path.

c. normal navigation on both the outward and homeward path.

d. random wandering around the nest with no attempt to forage.

e. a longer outward trip than usual and failure to compensate on the homeward path.

Type: multiple choice question

Title: Chapter 20 Question 16

16. In order to determine direction using polarized light, an ant must be able to see

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Explain how polarized light provides a navigation compass for many invertebrates.

Bloom’s Level: 2. Understanding

a. the sun, and its location in the sky.

b. the majority of the sky on a cloudless day (even if the sun itself is blocked).

c. the majority of the sky, even if it is overcast.

d. a small part of the sky that need not include the sun.

e. both the sun and an object reflecting the sun.

Type: multiple choice question

Title: Chapter 20 Question 17

17. Learning is required in order for ants to use these stimuli for navigation.

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Give two examples of how learning complements navigation mechanisms in ants.

Bloom’s Level: 2. Understanding

a. Odors that predict the location of food or the nest

b. How to use the location of the sun

c. How to discriminate between different orientations of light polarization

d. Visual landmarks that designate the location of food

e. Which pheromones predict food, and which predict other stimuli

Type: multiple choice question

Title: Chapter 20 Question 18

18. When ants are new to foraging, they maintain their orientation during “learning walks” by using these cues.

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Give two examples of how learning complements navigation mechanisms in ants.

Bloom’s Level: 2. Understanding

a. Light polarization

b. Geomagnetic cues

c. Nest odor

d. Pheromone trails

e. Internal pedometer

Type: multiple choice question

Title: Chapter 20 Question 19

19. The twisted rhabdomeres in certain ommatidia of the honeybee serve the function of allowing

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Explain the function served by the twisted receptors contained in certain ommatidia of bees.

Bloom’s Level: 2. Understanding

a. the bee to perceive geomagnetic fields.

b. the bee to detect stimuli in multiple directions at once.

c. detection of the sun’s location.

d. more accurate discrimination of light polarization.

e. more accurate color vision.

Type: multiple choice question

Title: Chapter 20 Question 20

20. The disadvantage of a visual receptor structure that responds selectively to polarized light is that

Feedback: Subhead: Navigation by Ants and Bees

Learning Objective: Explain the function served by the twisted receptors contained in certain ommatidia of bees.

Bloom’s Level: 2. Understanding

a. polarized light does not provide reliable directional cues.

b. polarized light depends on the location of the sun in the sky.

c. these receptors would be incapable of responding to the visible light spectrum.

d. color perception would depend on surface texture and direction of view.

e. these receptors could not function when the sky is cloudy.

Type: multiple choice question

Title: Chapter 20 Question 21

21. Neuroscientists have studied the mechanisms by which lobsters and crayfish are attracted to _______ and withdraw from _______.

Feedback: Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Discuss how experiments with crayfish have shown how the nervous system integrates visual information to produce motor responses.

Bloom’s Level: 1. Remembering

a. dim light; bright light

b. darkness; light

c. light; darkness

d. blue wavelengths; red wavelengths

e. red wavelengths; blue wavelengths

Type: multiple choice question

Title: Chapter 20 Question 22

22. In the crayfish optic nerve, “sustaining” neurons respond to more intense light by

Feedback: Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Discuss how experiments with crayfish have shown how the nervous system integrates visual information to produce motor responses.

Bloom’s Level: 2. Understanding

a. firing a train of action potentials at a higher rate.

b. firing a train of action potentials at a lower rate.

c. suppressing all firing activity.

d. producing short bursts of activity with a higher probability.

e. firing in an on–off pattern with a greater degree of synchrony.

Type: multiple choice question

Title: Chapter 20 Question 23

23. A command neuron is a specific type of neuron that coordinates

Feedback: Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Explain what command neurons are.

Bloom’s Level: 2. Understanding

a. sequences of motor responses.

b. multiple modalities of sensory input (e.g., auditory and visual stimuli).

c. orientation of photo receptors toward visual inputs.

d. multiple input neurons to fire in synchrony.

e. travel vectors based on polarized light and an internal pedometer.

Type: multiple choice question

Title: Chapter 20 Question 24

24. A neuron that, when stimulated, produces a complete escape response from a stimulus, is most likely a(n)

Feedback: Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Explain what command neurons are.

Bloom’s Level: 3. Applying

a. somatosensory neuron.

b. command neuron.

c. ommatidium.

d. postganglionic neuron.

e. caudal neuron.

Type: multiple choice question

Title: Chapter 20 Question 25

25. Experiments with crayfish have demonstrated that direct illumination of these receptive fields tends to produce a withdrawal rather than a forward walking response.

Feedback: Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Discuss how experiments with crayfish have shown how the nervous system integrates visual information to produce motor responses.

Bloom’s Level: 2. Understanding

a. Upper part of the eye and the tail

b. Upper part of the eye and the antennae

c. Lower part of the eye and the antennae

d. Lower part of the eye and the tail

e. Outer rim of the eye and the forelegs

Type: multiple choice question

Title: Chapter 20 Question 26

26. The mechanism by which a crayfish decides whether to approach or withdraw from illumination appears to be

Feedback: Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Discuss how experiments with crayfish have shown how the nervous system integrates visual information to produce motor responses.

Bloom’s Level: 2. Understanding

a. Mutual inhibition of sustaining neurons.

b. Complex interconnections in the visual cortex.

c. Whether or not sustaining neurons are activated.

d. Motor neurons that propel the legs either forward or backward.

e. a switch neuron in the caudal ganglion.

Type: multiple choice question

Title: Chapter 20 Question 27

27. Sequences of rhythmic behavior, such as backward walking in the crayfish and swimming in the leech, rely on

Feedback: Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Explain what central pattern generators (CPGs) are.

Bloom’s Level: 2. Understanding

a. the motor cortex section of the invertebrate brain.

b. repeated activity of the environmental stimulus that triggers the response.

c. specialized sensory receptors that detect body position.

d. specialized circuits called central pattern generators.

e. specialized motor neurons that innervate multiple muscle fibers.

Type: multiple choice question

Title: Chapter 20 Question 28

28. Compared to insect and crustacean models used in neuroscience, the leech has

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Discuss four reasons why the leech provides a model system for studying neurons at the individual level

Bloom’s Level: 1. Remembering

a. about one-tenth the number of neurons and simpler behavior.

b. about the same number of neurons and simpler behavior.

c. about the same number of neurons but more complex behavior.

d. about one-tenth the number of neurons and more complex behavior.

e. about the same number of neurons but they are easier to map.

Type: multiple choice question

Title: Chapter 20 Question 29

29. Scientists began studying leeches

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Discuss four reasons why the leech provides a model system for studying neurons at the individual level

Bloom’s Level: 1. Remembering

a. over 100 years ago, due to their widespread use in medicine.

b. in the 1960s with the advent of modern neuroscience.

c. in the early 2000s, when they were discovered for transgenic use.

d. in the early 2000s, when they were used to trace embryonic cells.

e. only recently, when their genome was sequenced.

Type: multiple choice question

Title: Chapter 20 Question 30

30. The central nervous system of the leech consists of

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Describe how the organization of the leech body contributes to its appeal as a neurobiological preparation.

Bloom’s Level: 2. Understanding

a. a brain near the head and a spinal cord.

b. a brain near the head and a tail ganglion.

c. one brain-like ganglion at each end and a large number of segmental ganglia.

d. one brain-like ganglion at each end and a central abdominal ganglion.

e. four equally-spaced segmental ganglia of similar size.

Type: multiple choice question

Title: Chapter 20 Question 31

31. One major strength of the leech as a model organism is the

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Describe how the organization of the leech body contributes to its appeal as a neurobiological preparation.

Bloom’s Level: 2. Understanding

a. central brain that acts as a switchboard for all sensory input and motor output.

b. large number of redundant neurons that produce strong field potentials.

c. variety of sensory systems that are comparable to those of humans.

d. consistency of identifiable neurons across ganglia and across individuals.

e. small size for housing in the laboratory.

Type: multiple choice question

Title: Chapter 20 Question 32

32. The segmental ganglia in the leech function by

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Describe how the organization of the leech body contributes to its appeal as a neurobiological preparation.

Bloom’s Level: 2. Understanding

a. relaying sensory information to the brain.

b. densely interconnecting with each other to form a network.

c. receiving motor commands from the brain and sending them to the correct destination.

d. independently receiving sensory input and controlling motor output to its segment.

e. None of the above

Type: multiple choice question

Title: Chapter 20 Question 33

33. In the leech, a central pattern generator (CPG) has been identified that is responsible for

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Describe how the organization of the leech body contributes to its appeal as a neurobiological preparation.

Bloom’s Level: 1. Remembering

a. chewing behavior.

b. antipredatory behavior.

c. annular erection (ridging of the skin).

d. swimming behavior.

e. the startle reflex.

Type: multiple choice question

Title: Chapter 20 Question 34

34. Motor neurons in the leech use this neurotransmitter to produce excitatory responses in muscle fibers.

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Describe how the organization of the leech body contributes to its appeal as a neurobiological preparation.

Bloom’s Level: 1. Remembering

a. Glutamate

b. Dopamine

c. Serotonin

d. Norepinephrine

e. Acetylcholine

Type: multiple choice question

Title: Chapter 20 Question 35

35. In the leech, AE neurons and L neurons, respectively, function to

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Describe how the organization of the leech body contributes to its appeal as a neurobiological preparation.

Bloom’s Level: 2. Understanding

a. detect light stimulation and strong stimulation of the skin.

b. detect chemicals related to food and those related to predators.

c. produce a skin-ridging response and a body-shortening response.

d. produce a body-shortening response and a swimming response.

e. facilitate habituation and sensitization.

Type: multiple choice question

Title: Chapter 20 Question 36

36. Connections between sensory and motor neurons in the leech employ

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Describe how the organization of the leech body contributes to its appeal as a neurobiological preparation.

Bloom’s Level: 2. Understanding

a. only electrical synapses.

b. chemical synapses including both ion channels and g-protein-coupled receptors.

c. primarily nicotinic receptors.

d. primarily glutamate as a neurotransmitter.

e. both chemical and electrical synapses.

Type: multiple choice question

Title: Chapter 20 Question 37

37. T, P, and N neurons in the leech respond to this type of stimulation.

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: List three types of sensory cells found in leech segmental ganglia.

Bloom’s Level: 2. Understanding

a. Illumination (photosensory)

b. Touch (mechanosensory)

c. Vibration (auditory)

d. Chemicals (chemosensory)

e. Internal movement (proprioceptive)

Type: multiple choice question

Title: Chapter 20 Question 38

38. Very light pressure to the skin of a leech will produce activity in a

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: List three types of sensory cells found in leech segmental ganglia.

Bloom’s Level: 1. Remembering

a. C cell.

b. P cell.

c. N cell.

d. T cell.

e. M cell.

Type: multiple choice question

Title: Chapter 20 Question 39

39. T, P, and N neurons in the leech differ by approximately this many expressed genes.

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: List three types of sensory cells found in leech segmental ganglia.

Bloom’s Level: 1. Remembering

a. One

b. Fewer than ten

c. About one hundred

d. About five hundred

e. Over a thousand

Type: multiple choice question

Title: Chapter 20 Question 40

40. If an S-cell is damaged or prevented from transmitting signals, the result is that

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Explain the function of the S cell in leech segmental ganglia.

Bloom’s Level: 2. Understanding

a. habituation is intact but sensitization is impaired.

b. sensitization is intact but habituation is impaired.

c. both habituation and sensitization are impaired.

d. the reflexive response to touch is eliminated.

e. the reflexive response to touch is strengthened.

Type: multiple choice question

Title: Chapter 20 Question 41

41. The function of S-cells appears to involve

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Explain the function of the S cell in leech segmental ganglia.

Bloom’s Level: 2. Understanding

a. serving as a central pattern generator (CPG).

b. producing a reflexive shortening response.

c. serving as a command neuron.

d. modulating the degree to which L motoneurons are excited by sensory input.

e. producing a bending response away from skin stimulation.

Type: multiple choice question

Title: Chapter 20 Question 42

42. Habituation in the leech can be demonstrated by

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Define habituation, dishabituation, and sensitization.

Bloom’s Level: 2. Understanding

a. repeatedly stimulating single L neurons with an electrode.

b. repeatedly touching the same body segment.

c. injecting long bursts of electric current into T neurons.

d. inducing the leech to move forward for an extended period of time.

e. injecting electric current into the segmental ganglia.

Type: multiple choice question

Title: Chapter 20 Question 43

43. Researchers induce habituation in two groups of leeches by repeatedly stimulating a section of skin on the leeches with a gentle stream of water. Following habituation, researchers use an electrode to stimulate a T cell (in Group 1) or an N cell (in Group 2) in a nearby part of the body. When subsequently stimulated with another gentle stream of water (in the original location), the researchers would likely expect to see

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Define habituation, dishabituation, and sensitization.

Bloom’s Level: 3. Applying

a. sensitization in both groups.

b. habituation in both groups.

c. habituation in Group 1, and dishabituation in Group 2.

d. dishabituation in Group 1, and sensitization in Group 2.

e. sensitization in Group 1, and habituation in Group 2.

Type: multiple choice question

Title: Chapter 20 Question 44

44. A researcher studying behavioral flexibility in the leech might expect to observe habituation after repeated stimulation of _______, and sensitization after repeated stimulation of _______.

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Define habituation, dishabituation, and sensitization.

Bloom’s Level: 3. Applying

a. S neurons; L neurons

b. photoreceptors; touch receptors

c. The skin; sensory neurons

d. N cells; T cells

e. T cells; N cells

Type: multiple choice question

Title: Chapter 20 Question 45

45. Serotonin (or 5-HT) levels in the leech have been linked to

Feedback: Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Not aligned

Bloom’s Level: 2. Understanding

a. swimming behavior.

b. eating behavior.

c. crawling behavior.

d. habituation.

e. sensitization.

Type: essay/short answer question

Title: Chapter 20 Question 46

46. Select one of the invertebrate models described in your textbook, and explain two advantages of using that model for neuroscience research.

Feedback: The leech offers several advantages over vertebrate models for neuroscience research. One of these is that leech ganglia have a small number of relatively large neurons, so that specific neurons can be identified and recorded. A second advantage is that leeches produce behavior that is complex enough to be interesting, such as rhythmic locomotion and habituation, but also simple enough to identify the neural circuitry that produces it.

Subhead: From Behavior to Neurons and Vice Versa

Learning Objective: List three advantages that invertebrates offer for studying how nerve cells integrate information to produce coordinated behavior.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 47

47. Imagine that you are a researcher interested in identifying the neural mechanisms responsible for a simple escape response from a strong (noxious) stimulus. What model would you select, and why?

Feedback: I would choose to use a crayfish model. The crayfish exhibits sophisticated locomotor behavior in response to a variety of stimuli (e.g. visual, touch), so could easily produce an escape response. Additionally, the neurons in a crayfish are relatively large, and easier to record from than those of alternative models such as an ant or a bee. Therefore, the crayfish provides a good balance of complexity and simplicity to answer my question.

(other animal models could also be correct, depending on justification presented)

Subhead: From Behavior to Neurons and Vice Versa

Learning Objective: List three advantages that invertebrates offer for studying how nerve cells integrate information to produce coordinated behavior.

Bloom’s Level: 3. Applying

Type: essay/short answer question

Title: Chapter 20 Question 48

48. Describe two stimuli that bees use to navigate through space.

Feedback: One stimulus used by bees is polarized light. Bees are able to detect the direction of polarization of light in order to determine where they are relative to the sun. Additionally, bees are able to use geomagnetic cues to help determine their location and direction of movement.

Subhead: Navigation by Ants and Bees

Learning Objective: Describe four different sensory systems that ants and bees use to navigate.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 49

49. What are the advantages of using polarized light rather than simply the location of the sun in the sky for the purpose of navigation?

Feedback: The major advantage of polarized light is that it can provide directional cues even when the sun is obscured, either on a cloudy day or behind trees or hills. This allows the ant or bee to navigate even if it can only see a small portion of the sky.

Subhead: Navigation by Ants and Bees

Learning Objective: Explain how polarized light provides a navigation compass for many invertebrates.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 50

50. Imagine that you are a researcher presented with a new species of ant that has not yet been studied. Your goal is to determine whether this new species can use polarized light to navigate in the same way as Cataglyphis bicolor. Describe one experiment that you would use to help answer this question.

Feedback: I would insert a polarizing filter that shifts the direction of polarization of the light while the ant navigates, to see whether this affects its homeward route. If it does, that would indicate that the ant is sensitive to polarized light in a way that is similar to Cataglyphis bicolor.

(many other experiments would also be appropriate)

Subhead: Navigation by Ants and Bees

Learning Objective: Explain how polarized light provides a navigation compass for many invertebrates.

Bloom’s Level: 3. Applying

Type: essay/short answer question

Title: Chapter 20 Question 51

51. Describe one way that learning plays a role in spatial navigation in ants.

Feedback: One of the ways that ants learn in navigation is when they are new to foraging. In order to remember the location of the nest, they walk in circles around the nest entrance to view it from multiple directions. This helps them to remember local cues signaling the location of the nest entrance.

Subhead: Navigation by Ants and Bees

Learning Objective: Give two examples of how learning complements navigation mechanisms in ants

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 52

52. What is the difference in structure and function between ommatidia in the dorsal rim of the bee eye, and in the other areas of the bee eye?

Feedback: Ommatidia in the dorsal rim of the eye have neatly stacked microvilli which are arranged to be maximally sensitive to specific directions of polarized light. In contrast, ommatidia in other regions are twisted so that their sensitivity is not selective to specific directions of polarization. This allows the bees to use some specialized ommatidia in the dorsal rim to detect polarization, while the rest of the ommatidia are better able to discriminate color.

Subhead: Navigation by Ants and Bees

Learning Objective: Explain the function served by the twisted receptors contained in certain ommatidia of bees.

Bloom’s Level: 4. Analyzing

Type: essay/short answer question

Title: Chapter 20 Question 53

53. What advantage do crayfish offer compared to ants and bees as subjects for the study of the organization of neuronal circuits?

Feedback: Compared to ants and bees, crayfish are capable of higher levels of behavior, meaning they are better subjects for investigating the detailed links between sensory input and motor performance.

Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Explain why crustaceans provide a better model for studying the organization of neuronal circuits than ants and bees do.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 54

54. Explain how an illumination stimulus can lead sometimes to withdrawal and sometimes to approach in crayfish.

Feedback: There are two mechanisms by which this decision is made. In the first, illumination to different visual fields leads to different responses; illumination of the upper part of the eye produces approach, while illumination of the lower part of the eye, and of the tail, induces withdrawal. Then, bundles of sustaining neurons receiving input from the upper eye, and those receiving input from the lower eye and the tail, mutually inhibit each other. This allows one dominant behavior to emerge and produce either approach or withdrawal.

Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Discuss how experiments with crayfish have shown how the nervous system integrates visual information to produce motor responses

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 55

55. What is a central pattern generator (CPG)?

Feedback: A CPG is a neural circuit that uses internal mutual excitation and inhibition to produce a rhythmic pattern of motor activity, leading to repetitive sequence of behavior such as swimming, flying, or walking.

Subhead: Deciding between Opposite, Incompatible Behaviors: Neuronal Circuits in the Crayfish

Learning Objective: Explain what central pattern generators (CPGs) are

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 56

56. Describe two features of the leech structure that make it especially useful for investigating how individual neurons produce behavior.

Feedback: One advantageous feature of the leech is that the segmental ganglia function largely independently of each other, which makes it simpler to analyze full circuits of sensory input to motor output. A second advantage is that the ganglia are consistently organized, allowing specific neurons to be easily identified.

Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Describe how the organization of the leech body contributes to its appeal as a neurobiological preparation

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 57

57. Explain the functions of the T, P, and N neurons in the leech.

Feedback: All three cells are somatosensory neurons with cell bodies in the segmental ganglia. T neurons respond preferentially to light touch of the skin, P neurons respond preferentially to stronger pressure on the skin, and N neurons respond to strong, potentially damaging contact with the skin. These synapse onto L motoneurons that produce a contraction response in the muscles.

Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: List three types of sensory cells found in leech segmental ganglia.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 58

58. What are the three types of sensory neurons found in leech segmental ganglia?

Feedback: The three types of neurons are T neurons, which respond to light touch, P neurons, which respond to stronger pressure, and N neurons which respond to strong (noxious) stimulation.

Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: List three types of sensory cells found in leech segmental ganglia.

Bloom’s Level: 1. Remembering

Type: essay/short answer question

Title: Chapter 20 Question 59

59. Explain the role of the S neuron in the leech.

Feedback: The S neuron is an interneuron that connects sensory inputs with motor outputs. A functional S neuron is required in order for sensitization of the body-shortening reflex to occur successfully.

Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Explain the function of the S cell in leech segmental ganglia.

Bloom’s Level: 2. Understanding

Type: essay/short answer question

Title: Chapter 20 Question 60

60. Explain how scientists induce habituation in the leech.

Feedback: Habituation can be produced by repeatedly touching a consistent location on the skin of the leech. Initially, this produces reflexive shortening of the body, but as the leech habituates, this reflex gradually weakens.

Subhead: Analysis at the Level of Individual Neurons: The CNS of the Leech

Learning Objective: Define habituation, dishabituation, and sensitization

Bloom’s Level: 2. Understanding