Anatomy and Physiology: Characteristics, Feedback Mechanisms, and Body Regions

Organization

Living things exhibit a high degree of organization, from the cellular level (cells, tissues, organs) to the organismal level.

Responsiveness

Living organisms react to stimuli in their environment.

Growth and Development

Living organisms increase in size and complexity over time.

Reproduction

Living things produce new organisms of their own kind.

Metabolism

This encompasses all the chemical reactions that occur within a living organism.

Homeostasis

This refers to the maintenance of a stable internal environment despite external changes.

Negative Feedback

The fundamental mechanism of Homeostasis, which is the body's ability to maintain a stable internal environment despite external changes.

Key Components of Negative Feedback

Receptors, Control Center, Effectors.

Positive Feedback

A biological mechanism that amplifies the effect of a stimulus, leading to a change in the body's state rather than maintaining a stable internal environment.

Anatomical Position

A standardized posture used as a reference point for describing body structures and locations.

Standing Upright

A position where the body is erect.

Facing Forward

The body is oriented with the front facing forward.

Arms at the Sides

The arms are positioned straight down alongside the body.

Palms Facing Forward

The palms are oriented to face forward.

Feet Flat on the Floor

The feet are positioned flat on the ground.

Feet Facing Forward

The feet are oriented to point straight ahead.

Directional Terms

Used to describe the location of body parts relative to each other.

Superior (or Cranial)

Refers to a position above or higher than another part.

Inferior (or Caudal)

Refers to a position below or lower than another part.

Anterior (or Ventral)

Refers to the front of the body.

Posterior (or Dorsal)

Refers to the back of the body.

Medial

Refers to a position closer to the midline of the body.

Lateral

Refers to a position further away from the midline of the body.

Proximal

Refers to a position closer to the point of attachment or origin.

Distal

Refers to a position further away from the point of attachment or origin.

Superficial

Refers to a position closer to the surface of the body.

Deep

Refers to a position further away from the surface of the body.

Body Cavities

Spaces within the body that contain vital organs.

Thoracic Cavity

Surrounded by the rib cage and separated from the abdominal cavity by the muscular diaphragm.

Abdominal Cavity

Bounded primarily by the abdominal muscles and contains the stomach, intestines, liver, spleen, pancreas, and kidneys.

Pelvic Cavity

Small space enclosed by the bones of the pelvis containing the urinary bladder, part of the large intestine, and internal reproductive organs.

Serous Membranes

The cavity between the visceral and parietal serous membranes is filled with serous fluid.

Visceral Layer

Covers the organs.

Parietal Layer

Lines the body cavity wall.

Abdominopelvic Cavity

The large body cavity located in the lower half of the trunk, encompassing both the abdominal and pelvic regions.

Subdivisions of Abdominopelvic Cavity

Includes abdominal cavity (digestive organs, kidneys, spleen) and pelvic cavity (reproductive organs, bladder, rectum).