Question 1

If a response increases a disturbance, the control system is classified as a ________ feedback system.

Accepted Answer

A positive feedback system is one in which the response reinforces or amplifies the disturbance, leading to an increase in the original signal. This can lead to unstable behavior or even a runaway response.

Question 2

The imaging technique that assesses metabolic and physiological activity of a structure is called a

Accepted Answer

PET scans use radioactive tracers to measure metabolic and biochemical activity in the body, making it the imaging technique that assesses metabolic and physiological activity of a structure. Ultrasound, digital subtraction angiography, MRI, and CT scans do not measure metabolic activity.

Question 3

The process that occurs when a cell, tissue, organ, or organ system adjusts in response to some environmental change is

Accepted Answer

The process described in the question is autoregulation, which refers to the ability of a cell, tissue, organ, or organ system to regulate its own activity in response to environmental changes. Autoregulation allows for a dynamic, self-adjusting state of equilibrium, which is distinct from the static state of equilibrium that is maintained through negative feedback. Positive feedback, on the other hand, amplifies a response rather than regulating it, and is therefore not applicable in this context.

Question 4

The ________ is the membrane that covers the internal organs.

Accepted Answer

The visceral serosa is the membrane that covers the internal organs. The parietal serosa is the membrane that lines the body cavities, while the mucous membrane lines the openings to the outside world (such as the respiratory and digestive tracts). The cutaneous membrane is another term for the skin. The term "serous membrane" refers to both the visceral and parietal serosa.

Question 5

When body temperature rises, a center in the brain initiates physiological changes to decrease the bodytemperature. This is an example of

Accepted Answer

Negative feedback is a process by which the output of a system (in this case, the rising body temperature) is inhibited or reversed by a stimulus (in this case, the center in the brain initiating physiological changes to decrease body temperature) in order to maintain a stable internal environment (i.e., homeostasis). This is what is happening in the given scenario, making option A the best choice. Positive feedback, on the other hand, amplifies or reinforces the output of a system, which is not the case here. Non-homeostatic regulation and diagnostic regulation are not relevant in this scenario. Fever is a condition in which the body temperature rises above normal and is not a physiological mechanism for maintaining homeostasis like negative feedback is.

Question 6

The tendency for physiological systems to stabilize internal conditions is called

Accepted Answer

Homeostasis refers to the ability of an organism to maintain stable internal conditions despite external changes. This is achieved through self-regulation of physiological systems, which work together to maintain equilibrium. Equilibriosis and hemopoiesis are not related to this concept, and amplification refers to the process of increasing a signal strength.

Question 7

The imaging technique that builds an image by using sound waves reflected by internal structures is calleda

Accepted Answer

The imaging technique described in the question, which uses sound waves to build an image of internal structures, is called ultrasound. PET scans, digital subtraction angiography, MRI, and CT scans all use different methods to create images, such as detecting radioactivity, injecting contrast agents, or using magnetic fields.

Question 8

Identify the structure located within the mediastinum.

Accepted Answer

The pericardial cavity is a structure located within the mediastinum. It is a sac that surrounds the heart and is filled with fluid to reduce friction during heart contractions. The other options listed are not located within the mediastinum.

Question 9

Which of the following imaging techniques is used to monitor blood flow through specific organs, such asthe brain, heart, lungs, and kidneys?

Accepted Answer

Digital subtraction angiography (DSA) is specifically used to visualize blood vessels and monitor blood flow through organs by subtracting pre-contrast images from post-contrast images, highlighting the blood vessels.

Question 10

A cell or an organ that responds to commands of the control center in negative feedback is termed a(n)

Accepted Answer

An effector is a cell or organ that responds to commands of the control center in negative feedback, producing a response that opposes the initial stimulus. A receptor detects changes in the internal or external environment and communicates this information to the control center, which then sends out commands to effectors. The hypothalamus is a region of the brain that serves as a control center for many homeostatic processes, including temperature regulation. Thermoregulators are organisms or devices that maintain a constant temperature, but this term does not apply to a cell or organ in negative feedback. Stimulus refers to any change in the internal or external environment that activates a receptor.

Question 11

________ results from the activities of the nervous or endocrine system.

Accepted Answer

Extrinsic regulation results from the activities of the nervous or endocrine system. This type of regulation involves responses to stimuli from outside the organ or system being regulated. Examples include the release of insulin in response to high blood sugar or the activation of the sympathetic nervous system in response to stress. Self-regulation, automatic regulation, intrinsic regulation, and autoregulation all refer to processes within an organ or system itself.

Question 12

This type of feedback exaggerates the effects of variations from normal.

Accepted Answer

Positive feedback amplifies changes or deviations from a norm, leading to an increase in the magnitude of the response.

Question 13

Which of the following imaging techniques causes particles within atoms to line up in uniform directionallowing the imaging of soft tissue?

Accepted Answer

MRI uses a strong magnetic field, radio waves, and a computer to cause the particles within atoms to line up in a uniform direction. This allows for the imaging of soft tissue.

Question 14

The maintenance of a relatively constant internal environment in an organism is termed

Accepted Answer

Homeostasis refers to the maintenance of a relatively constant internal environment in an organism, regardless of external changes. This is important for the proper functioning of cells, tissues, and organs, and is regulated by various feedback mechanisms. Positive feedback is a process that amplifies or reinforces a particular change, while negative feedback is a process that counteracts a particular change and restores equilibrium. Effector control and integration are related concepts, but they do not fully capture the complexity of homeostasis.

Question 15

Visceral pericardium is located

Accepted Answer

The visceral pericardium, also known as the epicardium, is the innermost layer of the pericardium and is located directly on the surface of the heart.

Question 16

Homeostatic regulation usually involves a(n) ________ that detects a particular stimulus, and a(n) ________that responds to the stimulus by communicating with a(n) ________ whose activity has an effect on the same stimulus.

Accepted Answer

Homeostatic regulation involves a receptor that detects a particular stimulus and communicates with a control center, which then sends signals to an effector to bring about a response. Therefore, the correct sequence is receptor → control center → effector, which is represented by choice C.

Question 17

The ________ is the membrane that covers the inner surface of cavity walls.

Accepted Answer

The parietal serosa is the correct answer because it refers to the part of the serous membrane that lines and adheres to the cavity wall, as opposed to the visceral serosa, which covers the organs (viscera) within the cavities.

Question 18

If a response decreases a disturbance, the control system is classified as a ________ feedback system.

Accepted Answer

A negative feedback system is one in which a response decreases a disturbance, whereas a positive feedback system is one in which a response increases a disturbance. The other answer choices are not relevant to this concept.

Question 19

The mediastinum

Accepted Answer

The mediastinum is the central compartment of the thoracic cavity, which separates the two pleural cavities (where the lungs are located) and includes the pericardial cavity (where the heart is located).

Question 20

The central principle of physiology is

Accepted Answer

Homeostasis is the central principle of physiology, which refers to the ability of the body to maintain a stable internal environment despite changes in external conditions. Physiological processes like temperature regulation, nutrition, reflexes, and stimulation are all essential for maintaining homeostasis, but they are not the central principle itself.

Quiz 1: An Introduction to Anatomy and Physiology