Chapter 1: The Human Organism - Vocabulary

Vocabulary flashcards covering the structural levels of organization, characteristics of life, microbiome, homeostasis, and feedback systems from Chapter 1.

Anatomy

The scientific discipline that investigates the body's structure.

Physiology

The scientific investigation of the processes or functions of living things.

Chemical Level

The structural level of organization involving the interaction of atoms.

Cell Level

The structural and functional unit of life.

Tissue Level

A level of organization composed of a group of similar cells and the extracellular matrix (ECM) surrounding them.

Organ Level

A level of organization consisting of one or more tissues functioning together.

Organ System Level

A level of organization consisting of a group of organs functioning together for a common purpose.

Organism Level

The highest level of structural organization, representing any living thing.

Microbiome

The microorganisms in the body or parts of the body (e.g., gut microbiome), or their collective genetic material.

Organization

The condition in which there are specific relationships and functions within an organism.

Metabolism

All chemical reactions that occur within the body.

Responsiveness

The ability of an organism to sense changes in its environment and adjust to them.

Growth

An increase in size and/or total number of cells.

Development

The changes an organism undergoes over time, usually referring to the embryonic period.

Differentiation

The developmental process of changing from a general cell type to a specific cell type.

Morphogenesis

The process involved in changing the shape of tissues and organs during growth and development.

Reproduction

The formation of new cells or new organisms.

Homeostasis

The process through which a nearly stable internal environment (milieu intérieur) is maintained in the body so that cellular functions can proceed at maximum efficiency.

Set Point

The ideal normal value of a physiological variable.

Receptor

A component of a feedback system that monitors the value of a specific physiological variable.

Control Center

A component of a feedback system that establishes the set point for a variable.

Effector

A component of a feedback system that can change the value of a variable.

Stimulus

A deviation from the set point that is detected by a receptor in a feedback loop.

Response

The action produced by an effector to influence the magnitude of a stimulus in a feedback system.

Negative-Feedback Mechanism

A homeostatic mechanism that counteracts a change in a variable by decreasing the deviation, returning the variable to its set point.

Positive-Feedback Mechanism

A feedback mechanism where a deviation from the set point produces a response that causes the deviation to become even greater in the same direction.

Total Body Water (TBW) Distribution

The breakdown of body fluid compartments in a $70\,\text{kg}$ person, consisting of $42\,\text{L}$ total body water ($60\%$ of body weight) divided into Intracellular Fluid ($28\,\text{L}$, $2/3$ of TBW) and Extracellular Fluid ($14\,\text{L}$, $1/3$ of TBW, composed of $80\%$ Interstitial Fluid and $20\%$ Plasma).