The Human Body: An Orientation

The Human Body – An Orientation Introduction Compare/contrast Anatomy & Physiology. Are the following considered Gross or Histology? Anatomy and physiology are always related. Structure determines function. Levels of organization: Simplest level is the atomic or chemical level. Levels of living structure: Cell Tissue Organ System Organism

Levels of Structural Organization Figure 1.1

II. System Overview Integumentary Skin (External covering) & its derivatives. Waterproofs, cushions and protects organs, regulates temperature and excretes salts, protects deeper tissue from injury. Figure 1.2a

Organ System Overview Skeletal Bones, cartilage and ligaments. Protects, provides framework, movement, stores minerals, produces blood cells. Figure 1.2b

Organ System Overview Muscular Skeletal muscles. Movement & produces heat. Figure 1.2c

Organ System Overview Nervous Nerves, brain and spinal cord. Fast-acting control system & responds to internal and external change. Figure 1.2d

Organ System Overview Endocrine Ductless glands. Controls slow, long lasting processes by producing hormones. Figure 1.2e

Organ System Overview Cardiovascular Heart, blood and vessels Transports materials and protects from invaders Figure 1.2f

Organ System Overview Lymphatic Lymph nodes, lymph and vessels. Returns fluid to blood and fight infection. Figure 1.2g

Organ System Overview Respiratory Nose, pharynx, larynx, bronchi, lungs and diaphragm. Brings in oxygen and removes carbon dioxide. Figure 1.2h

Organ System Overview Digestive Mouth, esophagus, stomach, SI, LI, liver and pancreas. Breaks down and absorbs food. Figure 1.2i

Organ System Overview Urinary Kidneys, ureter, urinary bladder and urethra. Filters wastes from the blood. Figure 1.2j

Organ System Overview Reproductive Ovaries, testes and accessory structures. Produce the gametes for reproduction. Figure 1.2k

III. Necessary Life Functions Characteristics of Living Things Maintain boundaries Move Responsiveness/Irritability Digestion Metabolism Excretion Growth Reproduction

III. Necessary Life Functions Survival needs Food, oxygen, water and appropriate temperature and atmospheric pressure. Feedback Positive: The response increases the effect of the control mechanism. Negative: The response stops the effect of the mechanism. (Most common)

III. Necessary Life Functions Control mechanism Communication within the body is essential for homeostasis. There are 3 components of a control mechanism. Receptor: sensor responding to changes. Control center: determines the maintained level and analyzes the information from receptors to determine proper response. Effector: The means for the control.

Overview of Homeostasis Figure 1.4

IV. The Language of Anatomy To prevent misunderstanding, there is a set of terms that allow structures to be easily located. Anatomical position In anatomy the body is always assumed to be in this position. The body standing straight, head and palms forward, arms out to the side.

Body Landmarks Figure 1.5a