The Human Body an orientation Chapter 1

Anatomy: The study of the structure and shape of the body and body parts and their relationship to one another.

Physiology: The study of how the body and its parts work or function

Structure and Function

Levels of Structural Organization: Atoms Molecules Cells Tissues Organs Organ System Organism

Integumentary System:

Skeletal System:

Muscular System:

Nervous System:

Endocrine System:

Cardiovascular System:

Lymphatic System:

Respiratory System

Digestive System

Urinary System:

Reproductive System:

Maintaining Life

How Do We Maintain Life? What functions of the human body are necessary to maintain life? Which organ systems contribute to each of the necessary life functions?

Maintaining Boundaries Why must living organisms maintain their boundaries? Name different “borders” in the body. What purpose do those borders serve? Skin Cell Membranes Organs

Movement Why do we need to be able to move? Manipulate our environment Respond to stimuli Obtain substances necessary for survival What systems are responsible? Skeletal Muscular What about movement of blood? Food? Urine?

Responsiveness What does the body need to respond to? External and internal What systems are involved? Detect changes and respond to those changes by activating the appropriate areas of the body.

Digestion What do we digest and why? Food needs to be broken down into simple molecules that can be absorbed by the body. What system is involved? (What happens once the food is digested?) The digestive system breaks the food down into simple molecules Molecules are absorbed into the blood and distributed by the circulatory system.

Metabolism What is metabolism? What Systems are involved? The sum of all the chemical reactions happening in the body. Breaking down complex substances into simpler ones, making larger structures from smaller ones, using oxygen and nutrients to produce ATP which powers all cellular activities. What Systems are involved? Digestive, Respiratory, cardiovascular, endocrine

Excretion Why is excretion necessary for maintaining life? Non-useful substances are produced during digestion and metabolism. What systems are involved? Digestive, Urinary, Respiratory, Integumentary

Reproduction What types of reproduction are necessary for maintaining life? Cellular, offspring What systems are involved? reproductive, endocrine

Growth and Development An increase in the overall number of cells results in growth. More cells are being made than are dying/being destroyed.

Survival The organ systems work together to ensure that the body can maintain all of the necessary life functions. However… it can not do it alone. Several factors must be available to the body in order for it to survive.

What does the body need in order to survive? nutrients oxygen water body temperature atmospheric pressure

Homeostasis Virtually every organ system plays a role in maintaining the constancy of the internal environment. Communication within the body is essential for homeostasis and is accomplished chiefly by the nervous and endocrine systems.

The elements of a control system:

Feedback Mechanisms Negative Feedback: Feedback that causes the stimulus to decline or end Positive Feedback: Feed back that tends to cause a variable to change in the same direction as the initial change. (enhances the stimulus)

The Language of Anatomy

Directional Terms Superior vs Inferior Superior- Towards the head Inferior - Away form the

Directional Terms Anterior vs Posterior Anterior – toward the front (ventral) Posterior – toward the backside (dorsal)

Directional Terms Medial vs Lateral Medial – toward the midline of the body Lateral – away from the midline of the body Intermediate – between a more medial and a more lateral structure.

Directional Terms Medial vs Lateral

Directional Terms Proximal vs Distal Proximal – close to the point of attachment to the trunk Distal – farther from the point of attachment to the trunk

Directional Terms Superficial vs Deep Superficial – Towards the surface of the body Deep – Away from the surface, more internal

Body Planes and Sections Sagittal Frontal Transverse

Body Cavities

Why Do We Have Body Cavities? Protection for delicate organs. You can run, jump, bump your head… They permit significant changes in size a shape. Organs can expand and contract without disturbing their neighbors.

The Dorsal Body Cavity Cranial Cavity = the space inside the skull, and it houses the brain Spinal Cavity = extends from the cranial cavity to the base of the vertebral column, and houses the spinal cord.

The Ventral Body Cavity Thoracic- enclosed by the muscles and bones of the chest wall and diaphragm =Most cardiovascular/respiratory organs Abdominopelvic - enclosed by the abdominal wall Abdominal = stomach liver and spleen, intestines Pelvic= reproductive organs, bladder and rectum