Question 1

What are the cells that are specialized to produce and conduct electrochemical impulses called?

Accepted Answer

Neurons are specialized cells of the nervous system that are responsible for generating and transmitting electrochemical impulses. Dendrites are extensions of neurons that receive signals from other neurons, while axons are extensions that transmit signals to other neurons or muscle cells. Fibroblasts are not part of the nervous system and are involved in the production of connective tissue, while astrocytes are supportive cells in the nervous system but do not generate or conduct impulses.

Question 2

Due to a mutation in a smooth muscle gene,the blood vessels in the skin of a certain strain of mouse become dilated when temperature falls below a certain point.Based on the likely outcome of this mutation,what precautions should the researchers take to maintain the health of their mice?

Accepted Answer

Since the blood vessels in the skin of the mutant mice dilate when temperature falls below a certain point, it is likely that they will have difficulty regulating their body temperature properly. Therefore, to maintain the health of these mice, the mouse room should be consistently maintained at a warm temperature to prevent them from undergoing fluctuations in temperature that could adversely affect their health.

Question 3

Damage to the integument may trigger action by cells of which system?

Accepted Answer

The immune system is responsible for protecting the body from foreign invaders and can also respond to damage in the integument (skin) by initiating an inflammatory response and sending white blood cells to the site of injury to help repair the damage. The other systems listed do not have a direct role in responding to damage in the integument.

Question 4

When we watch Olympic athletes perform,we are admiring the expert control of which systems working together?

Accepted Answer

Olympic athletes' performances require expert control of their nervous, muscular, and skeletal systems. The nervous system controls and coordinates movement, the muscular system produces force and movement, and the skeletal system provides structure and support for movement. The circulatory and endocrine systems also play important roles in athletic performance, but the control of movement primarily comes from the nervous, muscular, and skeletal systems.

Question 5

Where is the nucleus of a neuron found?

Accepted Answer

The nucleus of a neuron is found in the cell body, which is also known as the soma.

Question 6

The cell body of a motor neuron resides in the spinal cord,but it may control muscles a long distance away.In a giraffe,the ________ of a leg motor neuron may be six feet long!

Accepted Answer

The axon is the long, slender projection of a nerve cell that conducts electrical impulses away from the cell body to other neurons, muscles, or glands. In the case of a motor neuron controlling muscles in a giraffe's leg, the axon may extend up to six feet in length. The dendrites receive signals from other neurons and the cell body, also known as the soma, integrates these signals and generates an output signal through the axon. The node of Ranvier is a gap in the myelin sheath of nerve fibers where action potentials propagate.

Question 7

The axon of a neuron can only communicate with other neuronal cells.

Accepted Answer

The axon of a neuron can also communicate with muscle cells and gland cells, not just other neuronal cells.

Question 8

Which statement describes a home heating and cooling system that functions in a homeostatic way?

Accepted Answer

A home heating and cooling system that functions in a homeostatic way would have a thermostat that keeps the temperature within a narrow range, constantly monitoring and adjusting the heating or cooling to maintain a consistent temperature. This allows for energy efficiency and a comfortable living environment. Option A and B are extreme scenarios that do not describe a homeostatic system. Option C suggests a constant rate of heating, which may not be energy efficient or adaptable to changing environmental conditions.

Question 9

Homeostasis is maintained using negative feedback loops.Which part of a negative feedback loop detects conditions?

Accepted Answer

The sensor detects conditions and sends information to the integrating center, which then coordinates a response to bring the system back into balance. The effector carries out the response directed by the integrating center. The stimulus is the initial disturbance that triggers the feedback loop.

Question 10

Mechanisms that help generate heat and those that allow release of heat are an example of ________.Collectively,these mechanisms increase the ________ of body temperature.

Accepted Answer

Antagonist effectors work in opposition to each other; one set of effectors generates heat, while another set allows for the release of heat. This balance between heat production and heat release mechanisms increases the stability of body temperature.

Question 11

A bride-to-be is enjoying a manicure and a facial before her hair is styled for the wedding.What organ system is being pampered?

Accepted Answer

The integumentary system is being pampered as it includes the skin, hair, and nails, which are being treated during the manicure, facial, and hair styling. The lymphatic system helps to remove toxins from the body, the endocrine system regulates hormones, and the digestive system processes food. None of these systems are directly involved in the pampering the bride-to-be is receiving.

Question 12

A recovering stroke patient complained about strange smells in his room,but no cause could be found.The doctor diagnosed this as phantosmia,or olfactory hallucination,and said it was likely due to stroke-related damage to which tissue?

Accepted Answer

Phantosmia, or olfactory hallucination, is a condition related to the perception of smells that aren't present, and it can be caused by damage to the nervous system, such as from a stroke. This is because the nervous system includes the brain and other neural structures involved in processing sensory information, including smells.

Question 13

What structure do myelin sheaths form along?

Accepted Answer

Myelin sheaths form along axons, which are the long, thin extensions of a neuron that transmit nerve impulses.

Question 14

A couple is having difficulty conceiving a child,and they decide to see a fertility specialist.Which two organ systems will the specialist examine in this couple?

Accepted Answer

The reproductive system is an obvious choice as it is directly related to fertility. The endocrine system is also important as it is responsible for producing hormones that regulate the reproductive system. Additionally, the specialist may examine the urinary system to check for any issues that could be affecting fertility, such as a urinary tract infection. However, the nervous system is not directly related to fertility, and is therefore not as likely to be examined in this scenario.

Question 15

Which of the following is most likely to function as a defense system?

Accepted Answer

The integumentary system consists of the skin, hair, and nails, which serve as physical barriers against pathogens and other harmful substances. It also contains glands that secrete sweat and sebum, which can help to trap and remove bacteria and other toxins from the body. Therefore, the integumentary system is most likely to function as a defense system.

Question 16

In your Ph.D.research,you use thin slices of brain tissue to study neuronal signaling.You attach an electrode to a single neuron,but cannot detect any activity.What is the most likely explanation?

Accepted Answer

When brain tissue is sliced, it is possible to unintentionally sever the neuronal cell body from its dendrites, which are responsible for receiving signals from other neurons. Without these connections, the neuron will not exhibit any activity, even if an electrode is placed on it.

Question 17

Low body temperature triggers adaptive responses to conserve heat.Once the integrating center detects that body temperature has risen,it will decrease these responses.What does this exemplify?

Accepted Answer

The given statement describes a negative feedback loop, where the response to a change in a physiological variable (low body temperature) leads to a reversal of that change (conserving heat). Once the variable (body temperature) returns to the set point, the response stops. This is a characteristic of negative feedback mechanisms, which are essential in maintaining homeostasis in the body.

Question 18

Controversy surrounds the use of zinc-containing nasal sprays as a cold remedy,since they have been associated with anosmia (loss of smell).If true,this is likely due to the sprays damaging which tissue?

Accepted Answer

The sensory systems, specifically the olfactory epithelium in the nasal cavity, are responsible for the sense of smell. Damage to this tissue by zinc-containing nasal sprays could lead to anosmia.

Question 19

Which of the following systems is NOT directly involved with regulation and maintenance of the body's chemistry?

Accepted Answer

The reproductive system is primarily involved with the production of gametes (eggs and sperm) and the facilitation of fertilization and pregnancy, and is not directly involved with regulation and maintenance of the body's chemistry. The other systems listed (digestive, circulatory, respiratory, and urinary) are all directly involved with the intake, transport, and elimination of substances necessary for the body's chemistry.

Question 20

Why do some bread recipes suggest letting the dough rise in a warm place after kneading?

Accepted Answer

Yeast is a living organism that produces carbon dioxide as it metabolizes sugar in the dough. The warmer the environment, the faster the yeast will metabolize and produce carbon dioxide, causing the dough to rise more quickly. This is why some bread recipes suggest letting the dough rise in a warm place after kneading.

Quiz 41: The Animal Body and Principles of Regulation