A&P CH. 1

The elbow is proximal to the shoulder.

False

A coronal section divides an organ into superior and inferior portions.

False A transverse section divides an organ into superior (top) and inferior (bottom) portions.

The knee is proximal to the thigh.

False Proximal means "closer to the origin of the body part or the point of attachment of a limb to the body trunk." Distal means "farther from the origin of a body part or the point of attachment of a limb to the body trunk." In this case, because the thigh is closer to the body trunk than the knee, the knee is distal (not proximal) to the thigh.

A tissue consists of groups of similar cells that have a common function.

True

Positive feedback mechanisms tend to enhance the original stimulus so that the response is accelerated.

True

Homeostasis is the condition in which the body maintains ________.

a relatively stable internal environment, within limits

Which of the following is the regional term that includes the head?

axial The axial part of the body, which makes up the main axis of our body, includes the head, neck, and trunk.

The dorsal body cavity is the site of which of the following?

brain

The body cavities that protect the nervous system are located in the ________ cavity.

dorsal

Which of the following is an example of a positive feedback?

forming a platelet plug during blood clotting In order to prevent blood loss, the body needs a mechanism that amplifies the action that leads to clotting in a short period of time. This cascade or enhancement of a process is a positive feedback mechanism.

What is a vertical section through the body, dividing it into anterior and posterior regions called?

frontal

The study of large body structures, visible to the naked eye, such as the heart is called ________ anatomy.

gross

Which subdivision of anatomy would include the study of individual cells?

microscopic anatomy Microscopic anatomy is the study of cells, which cannot be seen by the naked eye.

A structure that is composed of two or more tissue types that work together to perform specific functions for the body is a(n) ________.

organ

Which level of structural organization is considered to be the highest (most complex) level? ANSWER:

organismal The highest level of organization is the organism, the living human being. Thus, the organismal level represents the sum total of all structural levels working together to keep us alive.

The anatomical position is characterized by all of the following EXCEPT ________.

palms turned posteriorly

Positive feedback differs from negative feedback because ________.

positive feedback tends to enhance the triggering stimulus while negative feedback tends to return the body to a homeostatic balance or "ideal" level

Some of the nerve endings in the skin are sensitive to changes in temperature. They are part of a negative feedback mechanism regulating body temperature. These nerve endings represent a(n) ________ in the negative feedback mechanism.

receptor

In a homeostatic control mechanism, which component monitors the environment?

receptor Homeostasis refers to maintenance of relatively stable internal conditions even though the outside world changes continuously. Receptors monitor changes occurring both inside and outside the body and send this information (called input) to control centers for processing.

What is a vertical section through the body, dividing it into left and right, called?

sagittal

Which of the following is NOT an example of the same level of structural organization as that represented by image 6?

smooth muscle Image 6 corresponds to the organ level of structural organization. Smooth muscle is a type of tissue and is shown in image 5.

Which directional term is used to describe the relationship of the skin to the skeletal muscles?

superficial The skin covers the outside of the body; thus, it is superficial, or external, to the skeletal muscles.

If the figure were used to represent the regulation of body temperature, the structures represented by the letter C could include __________.

sweat glands in the skin Effectors in the homeostatic control of body temperature include sweat glands and skeletal muscles.

Which of the following represents the correct order in which the components interact in a homeostatic control system?

the receptor, the control center, and the effector Regardless of the factor or event being regulated—the variable—all homeostatic control mechanisms are processes involving at least three components that work together. The first component, the receptor, is a sensor that monitors the environment and responds to changes by signaling (providing input to) the control center. The control center compares the input to the set point, which is the level or range at which a variable is to be maintained, and signals the appropriate effector(s). The effector produces the effect (change) that counteracts the initial problem (stimulus).

The dorsal body cavity is divided into which of the following subdivisions?

the vertebral/spinal and cranial cavities The dorsal body cavity, which protects the fragile central nervous system organs, has two subdivisions: the cranial cavity and the vertebral, or spinal, cavity.

Which of these is NOT part of the dorsal cavity?

thoracic cavity

What level of structural organization is represented by the image numbered 5 in the figure?

tissue Image 5 illustrates a type of tissue (in this case, muscle) consisting of a group of cells that work collectively to achieve a certain function.

Generally, what is the result of the negative feedback process?

to maintain homeostasis

Which of the following best defines anatomy?

It is the study of the structure of body parts and their relationships with one another.

Which of the following is the proper description of the human body in the anatomical position?

The body is erect with feet slightly apart, palms facing forward, and thumbs pointing away from the body. In the anatomical position, the body is erect with feet slightly apart and arms at the sides. This position is easy to remember because it resembles "standing at attention," except that the palms face forward and the thumbs point away from the body.

Why is the figure considered to be an example of a negative feedback system, as opposed to a positive feedback system?

The figure illustrates the correction of an imbalance back to a baseline. Negative feedback, even though it sounds like a bad thing, is what keeps your body systems within a proper working range by reversing trends that move the body away from a set point.

The ventral cavity includes which of the indicated subdivisions in the figure?

C, D, and E The ventral cavity includes the thoracic (C) and abdominopelvic cavities (D and E).