Human Physiology - Foundations and Homeostasis Vocabulary

Vocabulary practice flashcards covering introductory concepts in human physiology, structural levels of organization, body tissue types, fluid compartments, and mechanisms of homeostatic control.

Teleological approach

An approach to understanding body functions where explanations are provided in terms of meeting a specific bodily need.

Mechanistic approach

An approach to understanding body functions where explanations are framed in terms of cause-and-effect sequences, viewing the body as a machine.

Chemical level

The lowest level of structural organization comprising atoms (such as oxygen, carbon, hydrogen, and nitrogen making up $\thicksim 99$%) that combine to form molecules such as proteins, carbohydrates, fats, and nucleic acids.

Cellular level

The fundamental unit level of both structure and function in the body, representing the smallest unit capable of carrying out life processes.

Tissue level

A level of organization composed of groups of cells with similar structures and specialized functions, categorized into muscle, nervous, epithelial, and connective tissue.

Six levels of body organization

The structural hierarchy of the body consisting of the chemical level, cellular level, tissue level, organ level, body system level, and organism level.

Muscle tissue

A primary tissue specialized for contracting and generating force, consisting of skeletal, cardiac, and smooth muscle types.

Nervous tissue

A primary tissue consisting of cells specialized for initiating and transmitting electrical impulses, located in the brain, spinal cord, and nerves.

Epithelial tissue

A primary tissue specialized for exchanging materials between the cell and its environment, organized into epithelial sheets and secretory glands.

Lumen

A body cavity located within a hollow organ or tube.

Exocrine glands

Epithelial tissue derivatives specialized for secretion that excrete their products through ducts.

Endocrine glands

Epithelial tissue derivatives specialized for secretion that lack ducts and secrete internally into the blood.

Connective tissue

A primary tissue that connects, supports, and anchors various body parts, distinguished by having relatively few cells dispersed within abundant extracellular material.

Organ level

A structural level consisting of two or more primary tissue types functioning together to perform specific functions.

Body system level

A level of organization formed by collections of organs that perform related functions to interact and support the body across 11 major systems.

Organism level

The highest level of body organization in which all body systems function interdependently to maintain the whole body.

Homeostasis

The ability of a cell or organism to regulate its internal conditions using feedback systems to stay within a physiological range, such as $36\text{--}37^\text{o}\text{C}$.

Intracellular fluid (ICF)

The fluid contained within body cells.

Extracellular fluid (ECF)

The fluid located outside cells, comprised of plasma and interstitial fluid.

Plasma

The fluid portion of blood that forms part of the extracellular fluid.

Interstitial fluid

The fluid portion of extracellular fluid that directly surrounds cells.

Intrinsic controls

Local regulatory control mechanisms that are inherent in an organ.

Extrinsic controls

Regulatory control mechanisms initiated outside an organ, accomplished by the nervous and endocrine systems.

Negative feedback

A homeostatic mechanism where a sensor detects a change, a control centre compares it to a set point, and an effector produces a response that opposes the initial change.

Positive feedback

A homeostatic control system that amplifies or reinforces an initial change, moving a factor farther away from its set point.

Feedforward mechanisms

Control mechanisms that produce responses in anticipation of a change in a regulated factor before it occurs.

Pathophysiology

The abnormal functioning of the body associated with disease.