Question 1

How many pairs of cranial nerves do humans have?

Accepted Answer

Humans have 12 pairs of cranial nerves. These are responsible for various functions including sensory information, motor control, and autonomic functions of the head and neck region.

Question 2

A reflex arc involves a sensory neuron,a motor neuron,and a(n)__________ neuron.

Accepted Answer

The connector neuron, also known as an interneuron, is responsible for connecting the sensory neuron to the motor neuron in a reflex arc.

Question 3

Your instructor announces a "pop" test.You have not read the chapter yet.Your heart and breathing rate increases,and your mouth becomes dry.Which nervous system was responsible for this reaction?

Accepted Answer

The sympathetic nervous system is responsible for the "fight or flight" response, which includes an increase in heart rate, breathing rate, and dry mouth. This response is activated in situations of stress or perceived danger, such as facing a surprise test.

Question 4

Your instructor has just decided not to give the pop test that was announced at the beginning of class.The class breathes a collective "sigh of relief." This relief is best explained by which nervous system?

Accepted Answer

The parasympathetic nervous system is responsible for rest and relaxation responses, which include decreasing heart rate, lowering blood pressure, and reducing tension in muscles. Therefore, the collective sigh of relief in response to the news of no pop test is best explained by the parasympathetic nervous system.

Question 5

The reflex arc occurs when a stimulus provokes a(n)

Accepted Answer

The reflex arc is a neural pathway that involves the sensory neurons, interneurons, and motor neurons within the spinal cord to produce an automatic response without involvement from the brain. This allows for quick and automatic reactions to stimuli without requiring conscious thought or decision-making.

Question 6

Axons leaving the spinal cord

Accepted Answer

Axons leaving the spinal cord carry both sensory and motor messages.

Question 7

A barefoot child steps on a bee,then jerks his or her foot back in response to the sting.This response has likely involved all parts of the nervous system EXCEPT

Accepted Answer

The quick response to the bee sting is a reflex action that involves the sensory neurons receiving information about the sting and sending a signal to the spinal cord, which then sends a signal to the motor neurons causing the foot to jerk back. This response does not involve conscious thought or decision-making from the brain. Therefore, all parts of the nervous system are involved except for conscious or cognitive processing in the brain.

Question 8

The white matter in the spinal cord consists of

Accepted Answer

The white matter in the spinal cord consists of bundles of axons, which are nerve fibers covered with myelin, a fatty substance that helps with the rapid transmission of nerve impulses.

Question 9

Muscle fibers can contract because they are made up of

Accepted Answer

Muscle fibers are effector cells, which means they carry out the response or effect. They receive signals from motor neurons through neuromuscular junctions, causing them to contract. Neurilemma cells are a type of Schwann cell that produce myelin sheaths around axons in the peripheral nervous system. Connector neurons and sensory neurons are not directly involved in muscle contraction.

Question 10

Nerves that leave the brain directly are called __________ nerves.

Accepted Answer

Nerves that leave the brain directly are called cranial nerves. Spinal nerves arise from the spinal cord, sympathetic nerves are part of the autonomic nervous system, and peripheral nerves include both cranial and spinal nerves.

Question 11

The simplest behavior sequence,organized in the spinal cord,is the

Accepted Answer

A reflex arc is the simplest behavior sequence organized in the spinal cord. It involves a sensory neuron transmitting a signal to the spinal cord, which then activates a motor neuron to produce a reflex action without involving the brain. For example, the knee-jerk reflex. Autonomic and somatic reflexes also involve the spinal cord, but they are more complex as they involve the activation of multiple neural pathways and brain regions. Central synapse refers to the space between two neurons where neurotransmitters are released to transmit signals.

Question 12

Regarding the workings of your nervous systems,which of the following statements is FALSE?

Accepted Answer

The answer of Regarding the workings of your nervous systems,which...

Question 13

A nerve cell carrying information from your brain to muscles and glands is called a(n)

Accepted Answer

A motor neuron is responsible for carrying information from the brain to muscles and glands, allowing for movement and bodily functions.

Question 14

An advantage of having neural reflexes is that it

Accepted Answer

Having neural reflexes allows the brain to quickly and automatically respond to simple stimuli, freeing up cognitive resources for more complex decision-making tasks.

Question 15

The behavior sequence resulting from the actions of a sensory neuron,a connector neuron,a motor neuron,and an effector cell is a(n)

Accepted Answer

The described sequence is a reflex arc, which involves the transmission of sensory information through a sensory neuron, connection with a connector neuron, stimulation of a motor neuron, and ultimately activation of an effector cell. This process occurs rapidly and involuntarily in response to a stimulus and is responsible for many automatic and protective movements in the body.

Question 16

A nerve cell carrying information from your eyes,ears,fingers,etc.toward the CNS is called a(n)

Accepted Answer

A sensory neuron is responsible for carrying information from sensory receptors (such as those in the eyes, ears, and fingers) toward the central nervous system (CNS). Motor neurons, which carry information away from the CNS to muscles and glands, are not involved in this process. Effector cells and connector neurons are not specific types of nerve cells involved in sensory input.

Question 17

The usual flow of information in a reflex arc is

Accepted Answer

The flow of information in a reflex arc begins with a sensory neuron that detects a stimulus and sends the signal to a connector neuron in the spinal cord. The connector neuron then relays the signal to a motor neuron, which in turn activates the appropriate effector (muscle or gland). This sequence of events is known as a reflex arc, and the correct flow of information is sensory neuron, connector neuron, motor neuron. Choice B matches this sequence.

Question 18

You are watching a horror movie.The music changes to the familiar tune you recognize as a prelude to danger.You tense up,your heart rate increases,your breathing becomes shallow,your mouth is dry.Which nervous system has been activated?

Accepted Answer

The sympathetic nervous system is responsible for activating the fight or flight response, which includes increased heart rate, shallow breathing, and dry mouth. These are all physiological responses to a perceived danger such as what is experienced during a horror movie.

Question 19

How many pairs of spinal nerves do humans have?

Accepted Answer

Humans have 31 pairs of spinal nerves that emerge from the spinal cord and control the sensory and motor functions of the body.

Question 20

After rushing to catch the bus,when you find a seat and begin to relax,the return to your normal heart rate is under the influence of the

Accepted Answer

The parasympathetic branch of the autonomic nervous system is responsible for slowing down bodily functions and returning the body to a state of rest and relaxation. This includes a decrease in heart rate after physical activity or stress, such as rushing to catch a bus.

Quiz 2: A: Brain and Behavior