Human Anatomy and Physiology: Intro and Homeostasis

Vocabulary flashcards covering the course overview, grading policies, mechanics of homeostasis, and clinical terminology related to health and disease.

Homeostasis

The capacity to maintain a stable internal environment despite internal or external changes, maintained through dynamic equilibrium.

Negative feedback

A mechanism where the result of the action taken is contrary to the original stimulus sensed, reversing the change in the variable back to within its normal range.

Positive feedback

A mechanism that reinforces or strengthens the change in the controlled condition and is not part of homeostasis.

Afferent pathway

The route through which input is sent from the receptor to the control centre.

Efferent pathway

The route through which output is sent from the control centre to the effector.

Receptor (Sensor)

The component that detects a change or imbalance in the internal or external environment.

Control Centre

The component that assesses input and determines the response; while often the brain, it can also be located in organs like the kidneys.

Effector

The component that receives output from the control centre and provides the response to change the imbalance.

Normal human temperature range

The narrow range where humans function normally, between $36-37.5\,^{\circ}\text{C}$ ($96.8-99.5\,^{\circ}\text{F}$).

Fever (hyperthermia)

A condition defined by an internal temperature of $38\,^{\circ}\text{C}$ ($100.4\,^{\circ}\text{F}$).

Hypothermia

A condition defined by an internal temperature of $35\,^{\circ}\text{C}$ ($95\,^{\circ}\text{F}$).

Fatal temperature thresholds

Death typically occurs when internal temperatures go under $24\,^{\circ}\text{C}$ ($75.2\,^{\circ}\text{F}$) or above $44\,^{\circ}\text{C}$ ($111.2\,^{\circ}\text{F}$).

Disorder

Any abnormality of structure and/or function.

Disease

A disorder characterized by a recognizable set of symptoms and signs.

Symptom

An abnormality of function resulting from disease based on the subjective experience or description of the patient.

Sign

An abnormality of function resulting from disease based on visible and objective evidence that is measurable.

Diagnosis

The use of signs, symptoms, medical history, laboratory tests, and procedures to identify a disorder or condition.

Prognosis

A prediction about the possible course and/or outcome of a disease.