Ch 1: The Human Organism

Anatomy

Study of the body's structures.

Physiology

Study of the processes and functions of living things.

Chemical Level

The simplest level of organization; consists of atoms and molecules such as water, proteins, DNA, and glucose.

Cell Level

Level where molecules combine to form cells; the cell is the basic structural and functional unit of living organisms.

Tissue Level

Groups of similar cells and surrounding materials that perform a common function.

Organ Level

Two or more tissue types combined to form a structure with a specific function.

Organ System Level

Multiple organs working together to perform related functions.

Organism Level

All organ systems functioning together to make one living human.

Integumentary System

Protects the body, regulates temperature, and provides sensation.

Skeletal System

Provides support, protection, movement, mineral storage, and blood cell formation.

Muscular System

Responsible for movement, posture, and heat production.

Nervous System

Provides rapid communication and control throughout the body.

Endocrine System

Regulates body functions using hormones.

Cardiovascular System

Transports blood, gases, nutrients, wastes, and hormones.

Lymphatic System

Maintains fluid balance and provides immune defense.

Respiratory System

Performs oxygen and carbon dioxide exchange.

Digestive System

Breaks down food and absorbs nutrients.

Urinary System

Removes wastes and regulates fluid and chemical balance.

Reproductive System

Produces sex cells and enables reproduction.

Boundaries

Limits or barriers that separate the organism or its cells from the environment and regulate interactions.

Ingestion

Taking substances into the body through the mouth, such as eating or drinking.

Digestion

Breaking down substances from food into smaller molecules that the body can use.

Metabolism

Chemical processes that convert food and nutrients into energy and materials needed by the body.

Excretion

Elimination of metabolic wastes from the body.

Movement

The ability of the body or its parts to change position in response to needs or environmental conditions.

Reproduction

The production of new cells or a new organism.

Growth/Remodeling

Increase in size or changes in body structures in response to growth, use, or environmental demands.

Homeostasis

The body's ability to maintain a relatively stable internal environment.

Stimulus

A change in a variable that causes the body to respond.

Receptor

A structure that detects changes in the body's internal or external environment.

Control Center

Receives information from receptors and determines what response should occur.

Effector

A structure that carries out the response directed by the control center.

Negative Feedback

A response that opposes or reverses the original stimulus to return the body toward normal.

Positive Feedback

A response that increases or strengthens the original stimulus until a process is completed.

Superior

Toward or above another body structure.

Inferior

Toward or below another body structure.

Anterior

Toward the front of the body.

Posterior

Toward the back of the body.

Medial

Toward the midline of the body.

Lateral

Away from the midline of the body.

Proximal

Closer to the point of attachment or origin.

Distal

Farther from the point of attachment or origin.

Superficial

Toward or near the body's surface.

Deep

Away from the body's surface.

Sagittal Plane

Divides the body into left and right portions.

Midsagittal/Median Plane

Divides the body into equal left and right halves.

Parasagittal Plane

Divides the body into unequal left and right portions.

Frontal/Coronal Plane

Divides the body into anterior and posterior portions.

Transverse/Horizontal Plane

Divides the body into superior and inferior portions.

Body Cavities

Spaces within the body that contain and protect internal organs.

Dorsal Body Cavity

Posterior body cavity containing the cranial and vertebral cavities.

Cranial Cavity

Contains and protects the brain.

Vertebral Cavity

Contains and protects the spinal cord.

Ventral Body Cavity

Anterior body cavity containing the thoracic and abdominopelvic cavities.

Thoracic Cavity

Chest cavity located superior to the diaphragm.

Abdominopelvic Cavity

Cavity inferior to the diaphragm containing the abdominal and pelvic cavities.

Diaphragm

Muscle that separates the thoracic cavity from the abdominopelvic cavity.

Abdominal Cavity

Contains organs such as the stomach, liver, and intestines.

Pelvic Cavity

Contains structures such as the urinary bladder, reproductive organs, and rectum.

Serous Membranes

Membranes surrounding certain internal organs that help reduce friction as organs move.

Visceral Layer

The layer of a serous membrane that directly covers an organ.

Parietal Layer

The layer of a serous membrane that lines the wall of a body cavity.

Serous Fluid

Fluid between the visceral and parietal layers that reduces friction between moving