Review Questions

Review Questions

1. What is homeostasis?

Homeostasis is the tendency of a cell or the whole organism to maintain a state of balance.

2. What are the levels in the structural organization of the body?

The levels of the body are organized from the smallest to the largest. They are:

* Cells
* Tissues
* Organs
* Body systems (two or more organs)
* The human body as a whole

3. What are the components of the cell, and what are their functions?

The cell consists of these components:

* Cell membrane: the outer covering that controls the substances entering and leaving the cell

* Cytoplasm: the gel-like liquid inside the cell consisting of water, proteins, carbohydrates, lipids (fats), and salts

* Organelles: structures with specialized functions ranging from the nucleus, which controls cell activity including reproduction, to ribosomes, which produce protein for the cell structures

4. What are the four primary types of tissues?

The four primary types of tissues:

* Epithelial: covers the internal and external organs of the body

* Connective: holds parts of the body in place

* Nervous: transmits electrical impulses throughout the body to activate function

* Muscular: contracts and relaxes to cause or allow skeletal, smooth, and cardiac muscle function

5. What is the anatomical position?

The anatomical position is a view of the human body as it stands in a full upright position with the arms relaxed at the sides of the body, palms facing foreword, feet pointed foreword, and eyes looking straight ahead.

6. What are the three body planes and how do they divide the body?

The three body planes:

* Midsagittal plane: passes from the top to the bottom through the center, dividing the body into equal right and left halves

* Frontal plane: divides top to bottom through the center, and divides the body into front and back portions

* Transverse plane: divides the body horizontally into top and bottom portions

7. What are the main directional terms used for medical descriptions?

There are several directional terms used in medicine, none of which correspond to earth surface directions like north or west. Medical directions include the following:

* Lateral: away from the center of the body
* Medial: toward the center of the body
* Anterior: toward the front of the body
* Posterior: toward the back of the body
* Inferior: below
* Superior: above
* Caudal: closer to the lower back
* Cephalic: closer to the head
* Deep: farther from the body surface
* Superficial: close to the body surface
* Distal: farther from a reference point
* Peripheral: away from the center
* Proximal: closer to a reference point
* Apex: at the highest point
* Base: at the lowest point

8. What are the primary body cavities and what structures are in each one?

The primary body cavities:

* Cranial: skull, containing the brain

* Spinal: spinal column, containing the spinal cord

* Thoracic cavity: chest, containing the heart, lungs, and major blood vessels, and separated from the abdominal cavity by the diaphragm

* Abdominal cavity: in the abdomen, containing the stomach, intestines, liver, gallbladder, pancreas, and spleen

* Pelvic cavity: in the lower abdomen, containing the urinary bladder, rectum, and reproductive organs

9. What are the two methods used for describing the abdominal area?

The abdominal area can be described in the following ways:

* Divide the area into nine regions to describe specific areas with greater precision and clarity: epigastric (over the stomach); right and left hypochondriac regions (below ribs); umbilical (navel); right and left lumbar (either side of umbilical); hypogastric (below the stomach); right and left iliac regions (hip bone).

* Describe the abdomen in quadrants: upper quadrant (liver, gallbladder); right quadrant (appendix, some female reproductive organs); left quadrant (pancreas, stomach, spleen); left lower quadrant (some female reproductive organs).