Use illustrations to discuss relationship between structure and function. For example, the hand’s structure allows the function of grasping. Ask students to give an example of the relationship between structure and function, using a pet or an inanimate object. Pathophysiology is the branch of science that describes the consequences of the improper functioning of the body parts. Fig. 1-1
The basic unit of life is the cell. More complex organisms have tissues, organs, and even organ systems. Fig. 1-2
Groups of organs create organ systems. Each of the 12 human organ systems has a specific function.
The integumentary system forms a covering for the body, helps regulate body temperature, and contains some of the structures needed for sensation. The skeletal system forms the basic framework for the body and protects and supports body organs. The muscular system moves the skeleton and helps maintain body posture. Fig. 1-3
The afferent peripheral nervous system transmits information to the spinal cord and brain. The brain and spinal cord make and transmit decisions back to the body via efferent peripherals. The circulatory system pumps and transports blood throughout the body, carrying nutrients and oxygen to cells and waste away from them. The endocrine system secretes hormones that regulate body activities such as growth, reproduction, metabolism, and water balance. Fig. 1-3
The lymphatic system helps defend the body against pathogens and other foreign material. It also plays an important role in fluid balance. The digestive system breaks down the food we eat into substances that can be absorbed by the body. It also eliminates the waste products formed during this process. The respiratory system brings oxygen-rich air into the lungs and removes carbon dioxide–rich air from the lungs. Fig. 1-3
The urinary system excretes waste products from the body through the urine. It also helps control the amount of water and other substances in the body. The reproductive system enables humans to reproduce. The immune system (not shown) works with the lymphatic system to protect the body from pathogens and foreign substances. Fig. 1-3
The word “homeostasis” comes from Greek and Latin words meaning “staying the same”: homeo- is a prefix meaning “same,” and -stasis is a suffix meaning “staying.” Homeostatic functions allow conditions in the body to remain the same when homeostasis is achieved despite external challenges. Hundreds of homeostatic mechanisms help the body maintain homeostasis and help prevent disease or dysfunction caused by homeostatic imbalance.
Remembering that the palms face forward is especially helpful for identifying the bones and muscles of the arms. Anatomical position is the mirror image to the viewer’s position. Fig. 1-4
Superior means above and inferior below. Anterior means front and posterior back. Medial means toward the midline and lateral away from it. Proximal means near the point of attachment and distal means farther away from it. Superficial means near the surface and deep means below it. Central means center; peripheral means away from it. How is the elbow both distal to the shoulder and proximal to the wrist? The elbow is farther from the point of attachment than the shoulder, but it is nearer the point of attachment than the wrist.
Each plane divides the body with an imaginary line in one direction. If the cut is made exactly down the midline of the body and the right and left halves are equal, this is a midsagittal section. The frontal plane creates the front and back parts of the body. It is also known as the coronal plane. Horizontal and transverse “cuts” are called cross sections. Ask students to demonstrate these planes on a partner with a piece of paper. Fig. 1-5
Regional terms refer to the different regions or areas of the body. Figure 1-6 illustrates the regional terms for both the anterior and posterior surfaces of the body.
The thoracic cavity is divided by the mediastinum, which contains the heart, part of the esophagus, trachea, thymus gland, and the blood vessels of the heart. The right and left lungs are located on either side of the mediastinum. They are located in the pleural cavities. The abdominopelvic cavity consists of an upper portion, called the abdominal cavity, and a lower portion, called the pelvic cavity. Thoracic and abdominopelvic cavities are separated by the diaphragm.
The abdominal cavity contains the stomach, most of the intestine, liver, gallbladder, pancreas, spleen, and kidneys. The pelvic cavity contains the remainder of the intestines, rectum, urinary bladder, and internal parts of the reproductive system. The abdominopelvic cavity is quite large. In the health care setting, the surface of the abdominopelvic cavity is often described in terms of quadrants and regions. Fig.1-8
The Human Body in Health and
Illness, 4th edition
Introduction to the