Introduction to Human Anatomy & Physiology

These flashcards cover the foundational concepts of human anatomy and physiology, including levels of organization, organ systems, homeostasis, and anatomical terminology based anatomical terminology.

Anatomy

The study of internal and external body structures and the physical relationships among parts, derived from the Greek words 'ana' (up) and 'tome' (cutting).

Physiology

The study of how living organisms perform vital functions, focusing on mechanisms at cellular, organ, and systemic levels.

Principle of Complementarity of Structure and Function

The concept that anatomy and physiology are inseparable because function always reflects structure.

Hierarchical Levels of Structural Organization

The 6 distinct levels of the human body: Chemical, Cellular, Tissue, Organ, Organ System, and Organismal.

Integumentary System

The organ system composed of skin, hair, nails, and glands that provides protection, temperature regulation, and vitamin D synthesis.

Skeletal System

Provides structural support and protection, acts as a lever system, stores minerals like $Ca^{2+}$ and $PO_{4}^{3-}$, and performs hematopoiesis.

Hematopoiesis

The process of blood cell production specifically occurring in the red bone marrow.

Muscular System

Composed of skeletal muscles and tendons; functions include locomotion, posture maintenance, and thermogenesis (heat production).

Nervous System

Responsible for rapid internal communication, integration of sensory input, and regulation of muscular or glandular responses via the brain, spinal cord, and nerves.

Endocrine System

Provides long-term regulation of body activities through chemical messengers called hormones released into the bloodstream.

Cardiovascular System

Consists of the heart, blood vessels, and blood to transport oxygen, $CO_{2}$, nutrients, and hormones while maintaining pH and thermal balance.

Lymphatic & Immune System

Returns fluid leakage to the blood, absorbs dietary lipids, and mounts immune responses against pathogens.

Respiratory System

Facilitates gas exchange ($O_{2}$ supply and $CO_{2}$ elimination) and regulates blood acid-base balance (pH).

Digestive System

Involved in the mechanical and chemical breakdown of food, nutrient absorption, and the elimination of indigestible solid waste.

Urinary (Renal) System

Eliminates nitrogenous wastes like urea and creatinine, regulates water, electrolyte, and acid-base balance, and regulates blood pressure via the Renin-Angiotensin System.

Reproductive System

Functions in the production of gametes, secretion of sex hormones, and the perpetuation of the species.

Homeostasis

The ability of an organism to maintain a stable, relatively constant internal environment despite continuous external or internal fluctuations.

Dynamic Equilibrium

A key concept of homeostasis where internal conditions are not static but oscillate within a narrow physiological set point or range.

Receptor (Sensor)

The homeostatic component that detects changes in a physiological variable (stimulus) and sends input data via an afferent path.

Control Center (Integrator)

Processes input against a physiological set point and determines the appropriate response, such as the Hypothalamus.

Effector

An organ, gland, or tissue that executes the response from the control center to alter the stimulus and restore balance.

Negative Feedback Mechanism

The primary homeostatic mechanism where the response reverses or negates the initial direction of the stimulus to return the variable toward its set point.

Positive Feedback Mechanism

A rare, self-limiting process where the response amplifies or enhances the initial change in the stimulus, such as during blood clotting or childbirth.

Standard Anatomical Position

A universal reference baseline where the body stands erect, head/eyes/toes face anteriorly, and palms face forward (supinated).

Superior (Cranial)

Anatomical directional term meaning toward the head.

Proximal

Anatomical directional term meaning closer to the point of origin or attachment.

Ipsilateral

Anatomical directional term meaning on the same side of the body.

Axial Region

The main central axis of the body, including the head, neck, and trunk.

Appendicular Region

The upper and lower limbs (appendages) attached to the axial skeleton.

Antecubital

The anterior surface of the elbow, known as the primary site for routine phlebotomy.

Plantar

The sole of the foot, identified as the site for capillary heel sticks in neonates.

Sagittal Plane

A vertical cut dividing the body into right and left portions.

Midsagittal (Median) Plane

A vertical cut dividing the body exactly down the midline into equal halves.

Coronal (Frontal) Plane

A vertical cut dividing the body into anterior (front) and posterior (back) portions.

Transverse Plane

A horizontal cut dividing the body into superior (top) and inferior (bottom) portions.

Ventral Cavity

Located at the anterior of the trunk, containing the thoracic and abdominopelvic cavities.

Dorsal Cavity

Located at the posterior of the body, containing the cranial and spinal cavities.

Epigastric Region

The upper central abdominopelvic region containing the stomach, liver, pancreas, duodenum, spleen, and adrenal glands.

Hypogastric Region

The lower central abdominopelvic region containing the urinary bladder, sigmoid colon, and female reproductive organs.