Human Anatomy & Physiology – Orientation

Vocabulary flashcards covering key concepts from the lecture on human body orientation, including organizational levels, body systems, life functions, homeostasis, directional terms, planes, cavities, and regional anatomy.

Anatomy

Study of the structure and shape of the body and its parts.

Physiology

Study of how the body and its parts work or function.

Gross Anatomy

Branch of anatomy dealing with large structures that are easily observable without magnification.

Microscopic Anatomy

Study of structures too small to be seen with the naked eye; requires a microscope.

Chemical Level

Smallest level of organization where atoms combine to form molecules.

Cellular Level

Level at which cells are formed from molecules and are the basic units of life.

Tissue Level

Level where similar cells combine to form tissues.

Organ Level

Level in which different tissues combine to form organs with specific functions.

Organ System Level

Level where different organs work closely together to accomplish a common purpose.

Organismal Level

Highest level of organization; the living human being composed of many organ systems.

Integumentary System

External body covering that protects deeper tissue, synthesizes vitamin D, and houses cutaneous receptors and glands.

Skeletal System

Protects and supports organs, provides framework for muscle action, forms blood cells, and stores minerals.

Muscular System

Allows movement, maintains posture, and produces heat through skeletal muscle contractions.

Nervous System

Fast-acting control system that responds to internal and external changes by activating muscles and glands.

Endocrine System

Slow-acting control system that secretes hormones regulating growth, reproduction, and metabolism.

Cardiovascular System

Transports blood carrying oxygen, carbon dioxide, nutrients, and wastes via the heart and blood vessels.

Lymphatic System

Returns leaked fluids to blood, disposes of debris, and houses immune cells for defense.

Respiratory System

Keeps blood supplied with oxygen and removes carbon dioxide through gas exchange in the lungs.

Digestive System

Breaks down food, absorbs nutrients into blood, and eliminates indigestible material as feces.

Urinary System

Eliminates nitrogenous wastes, regulates water, electrolytes, and acid–base balance of the blood.

Reproductive System

Overall function is production of offspring; testes produce sperm and hormones, ovaries produce eggs and hormones.

Maintain Boundaries

Life function where the body keeps internal environment distinct from external environment.

Movement

Life function involving locomotion and transportation of substances within the body.

Responsiveness

Ability to sense changes (stimuli) and react to them.

Digestion (life function)

Breakdown of ingested food and absorption of simple molecules into the blood.

Metabolism

All chemical reactions in the body, including catabolism and anabolism, producing energy and regulated by hormones.

Excretion

Process of removing wastes produced by metabolism, e.g., in urine or feces.

Reproduction (life function)

Cellular or organismal process that produces future generations.

Growth

Increase in body size through cell size enlargement and/or cell number increase.

Nutrients

Chemical substances used for energy and cell building, including carbs, proteins, lipids, vitamins, and minerals.

Oxygen

Element required for most chemical reactions that release energy from foods.

Water

Most abundant chemical in the body (60–80%); vital for metabolic reactions.

Stable Body Temperature

Internal temperature of about 37 °C (98 °F) necessary for normal metabolic reactions.

Atmospheric Pressure

The force exerted by the weight of air; must be appropriate for proper gas exchange.

Homeostasis

Maintenance of a stable internal environment; dynamic state of equilibrium essential for life.

Negative Feedback

Homeostatic mechanism that reduces or shuts off the original stimulus, e.g., body thermostat.

Positive Feedback

Mechanism that enhances or amplifies the original stimulus, seen in blood clotting and childbirth.

Receptor

Sensor that monitors the environment and responds to stimuli by sending information to the control center.

Control Center

Determines the set point, analyzes input, and determines the appropriate response.

Effector

Provides the means for the control center’s response to the stimulus.

Superior (Cranial)

Directional term meaning toward the head or upper part of a structure; above.

Inferior (Caudal)

Directional term meaning away from the head; below.

Anterior (Ventral)

Toward or at the front of the body; in front of.

Posterior (Dorsal)

Toward or at the backside of the body; behind.

Medial

Toward or at the midline of the body; inner side.

Lateral

Away from the midline of the body; outer side.

Proximal

Closer to the origin of a body part or point of limb attachment to the trunk.

Distal

Farther from the origin of a body part or point of limb attachment to the trunk.

Superficial

Toward or at the body surface.

Deep

Away from the body surface; more internal.

Sagittal Plane

Body plane that divides the body into left and right parts.

Midsagittal (Median) Plane

Sagittal plane that divides the body into equal left and right halves.

Frontal (Coronal) Plane

Body plane that divides the body into anterior and posterior parts.

Transverse (Cross) Plane

Body plane that divides the body into superior and inferior parts.

Dorsal Body Cavity

Cavity consisting of the cranial cavity (brain) and spinal cavity (spinal cord).

Ventral Body Cavity

Cavity that includes thoracic cavity and abdominopelvic cavity.

Thoracic Cavity

Part of ventral cavity housing heart, lungs, and mediastinum.

Abdominopelvic Cavity

Cavity containing digestive organs, urinary organs, and reproductive organs.

Right Upper Quadrant (RUQ)

Abdominal quadrant containing liver, gallbladder, and portions of intestines.

Left Upper Quadrant (LUQ)

Abdominal quadrant containing stomach, spleen, and portions of intestines.

Right Lower Quadrant (RLQ)

Abdominal quadrant containing cecum, appendix, and portions of small intestine.

Left Lower Quadrant (LLQ)

Abdominal quadrant containing portions of descending and sigmoid colon.

Epigastric Region

Central upper region of the nine-region division; contains majority of the stomach.

Umbilical Region

Center region around the navel; contains portions of small intestine and transverse colon.

Hypogastric (Pubic) Region

Lower middle region; contains urinary bladder and initial part of sigmoid colon.

Right Hypochondriac Region

Upper right region; contains liver and gallbladder.

Left Hypochondriac Region

Upper left region; contains spleen and diaphragm portion.

Right Lumbar Region

Middle right region; contains ascending colon of large intestine.

Left Lumbar Region

Middle left region; contains descending colon of large intestine.

Right Iliac (Inguinal) Region

Lower right region; contains cecum and appendix.

Left Iliac (Inguinal) Region

Lower left region; contains initial part of sigmoid colon.