Physiology and Homeostasis Flashcards

These flashcards cover key concepts in physiology, focusing on the functioning of organ systems, mechanisms of homeostasis, and responses to internal and external changes.

Physiology

The science of life that studies how living organisms function under normal conditions.

Mechanisms

Biological processes that explain how structures produce life functions.

Normal physiology

The study of how the body operates under healthy conditions.

Pathophysiology

Applies physiological principles to understanding and treating disease.

Critical care medicine

Applies physiological principles to the care of seriously ill patients.

General physiology

Includes principles that apply across all organ systems.

Nervous system

Controls and regulates other organ systems using electrical and chemical signals.

Muscular system

Enables movement through muscle contraction acting on bones.

Metabolism

Includes all chemical reactions required to maintain life.

Respiratory system

Allows oxygen uptake and carbon dioxide removal.

Cardiovascular system

Circulates blood to deliver oxygen and nutrients.

Vasculature

The network of blood vessels in the body.

Diffusion distance

The minimal distance substances must travel from blood to cells.

Urinary system

Filters blood and removes metabolic waste.

Digestive system

Absorbs nutrients for cellular use.

Endocrine system

Regulates body functions using hormones.

Capillaries

Sites where exchange occurs between blood and tissues.

Homeostasis

Maintains a stable internal environment despite stress.

Regulated variables

Physiological parameters maintained within a narrow range.

Dynamic constancy

Fluctuation within acceptable limits rather than a fixed value.

Internal disturbances

Internal changes such as altered metabolism that affect balance.

External disturbances

Environmental influences that challenge balance.

Levels of organization

Describe the hierarchical structure of the body.

Intracellular fluid (ICF)

Maintains the internal environment of the cell.

Interstitial fluid/Extracellular fluid (ECF)

Regulates conditions within groups of similar cells.

Systemic regulation

Coordinates regulation across multiple organs.

DNA/Genes

Contain instructions for cellular structure and function.

Autonomic nervous system (ANS)

Regulates involuntary physiological processes.

Behavioral responses

Conscious actions taken to maintain balance.

Homeostatic control system/feedback loop

A control system maintaining physiological stability.

Sensors/Receptors

Detect changes in regulated variables.

Integrating center/Control center

Processes sensory input and determines responses.

Effectors

Carry out the corrective response.

Mean arterial pressure (MAP)

The average pressure driving blood flow.

Baroreceptors

Detect changes in arterial pressure.

Medullary cardiovascular center

Integrates cardiovascular reflexes in the brainstem.

Bradycardia

A decrease in heart rate.

Vasodilation

Widens blood vessels to reduce pressure.

Carotid sinus baroreceptors

Monitor blood pressure to the brain.

Aortic arch baroreceptors

Monitors pressure leaving the heart.

Aortic nerve

Transmits signals from the aortic arch.

Carotid sinus nerve

Transmits signals from the carotid sinuses.

Nucleus tractus solitarius (NTS)

The primary cardiovascular sensory integration center.

Parasympathetic nervous system

Decreases heart rate and conserves energy.

Sympathetic nervous system

Increases heart rate and vascular tone.

Vagus nerve

Slows the heart via parasympathetic activity.

Cardiac sympathetic nerves

Speeds the heart via sympathetic activity.

Vasoconstriction

Narrows blood vessels to raise pressure.

Venoconstriction

Increases venous return.

Sinoatrial (SA) node

The heart's natural pacemaker.

Contractility

Describes the force of heart contraction.

Arteriosclerosis

Stiffens arteries and impairs pressure sensing.

Aging

Reduces vessel elasticity and receptor sensitivity.

Baroreceptor transduction

Converts vessel stretch into neural signals.