Introduction to Structural Units and Body Systems

All living matter is made up of cells. Cells are the smallest units of life and the basic building blocks composing the human body.
Cells organize to make tissues.
Tissues organize to make organs.
Organs make up the major systems of the body.

In this segment we will cover these body systems in a brief introduction so you can familiarize yourself with each one before studying each one as a separate unit. This is just a basic primer for people who may be considering going into the field of medical transcription or working in a medical office.

The integumentary system is the outermost covering of the human body. It's the system we know mainly as our skin. Skin is classified as an organ. The integumentary system is also comprised of nails, hair, sebaceous glands and sweat glands.

The skeletal system is the innermost system of the body and is made up of membranes, bones and cartilage.

The muscular system is made up of fibrous connective tissues, bursae, tendons and muscles.

The nervous system is made up of all the nerves in the body. It includes sensory and motor structures, peripheral nerves, cranial nerves, the brain and the spinal cord.

The endocrine system is made up of the glands. The pituitary gland is the main gland of the body and controls the other glands. The other glands that made up the endocrine system are the ovaries, the testes, thyroid and the adrenals.

The cardiovascular system is made up of the heart, arteries, veins, and capillaries. It is also known as the circulatory system.

The lymphatic system contains lymph nodes, lymphatic vessels, the spleen and the thymus gland. It is better known as the immune system.

The respiratory system contains the lungs, the bronchi, trachea, nasal cavities, the pharynx and the larynx.

The digestive system is made up of the stomach, the intestines, the mouth, the esophagus, the rectum and the anus. It is also related to and works in conjunction with the liver, the pancreas and the salivary glands.

The urinary system contains the kidneys, the bladder, the urethra and the ureters.

The reproductive system contains the uterus, ovaries, uterine tubes and the vagina in the female. It contains the penis, the testes, vas deferens, seminal vesicles, the prostrate gland and the urethra in the male.

These are the 11 systems that make up the human body. They all work seperately but also together as a whole to keep the body functioning. More in depth information for each system will be covered in subsequent articles.