Chapter 1: The Human Body: An Orientation

Vocabulary practice flashcards covering basic terminology, levels of structural organization, organ systems, directional terms, planes, cavities, and homeostasis mechanisms from Chapter 1.

Biology

The study of life.

Anatomy

The study of internal and external body structures and their physical relationships.

Physiology

The study of how living organisms perform vital functions.

Gross Anatomy

Also known as macroscopic anatomy; the study of relatively large structures and features visible to the unaided eye, including regional, systemic, sectional, and surface anatomy.

Cytology

A branch of microscopic anatomy that analyzes the internal structure of individual cells.

Histology

A branch of microscopic anatomy that examines tissues and tissue structures.

Homeostasis

A state of body equilibrium or stable internal balance maintained by the body.

Receptor

A sensor that is sensitive to a particular stimulus or environmental change in homeostatic regulation.

Control Center

A homeostatic mechanism component that receives and processes information from the receptor and sends commands.

Effector

A cell or organ in homeostatic regulation that responds to commands from the control center to oppose or enhance the stimulus.

Negative Feedback

A homeostatic regulatory mechanism where a stimulus varies outside normal limits, triggering an automatic response that corrects or opposes the situation.

Positive Feedback

A homeostatic mechanism where the initial stimulus produces a response that reinforces and accelerates that stimulus.

Thermoregulation

A negative feedback mechanism governed by the thermoregulatory center in the brain (hypothalamus) that keeps body temperature fluctuating within an acceptable range, usually between $36.7^\bullet\text{C}$ and $37.2^\bullet\text{C}$.

Blood Clotting Process

An escalating positive feedback loop where damaged cells in the blood vessel wall release chemicals that initiate clotting, causing each step to release chemicals that further accelerate the process until a blood clot patches the vessel wall.

Superior

Directional term meaning above, at a higher level in the human body, or toward the head.

Inferior

Directional term meaning below, at a lower level, or toward the feet.

Anterior (Ventral)

Directional term referring to the front surface or belly side of the body.

Posterior (Dorsal)

Directional term referring to the back surface or back of the body.

Medial

Directional term meaning toward the midline of the body.

Lateral

Directional term meaning away from the midline of the body.

Proximal

Directional term referring to limbs, meaning toward the point of attachment of a limb to the trunk.

Distal

Directional term referring to limbs, meaning away from the point of attachment of a limb to the trunk.

Superficial

Directional term meaning at, near, or relatively close to the body surface.

Deep

Directional term meaning toward the interior of the body and farther from the surface.

Cranial (Cephalic)

Directional term meaning toward the head.

Caudal

Directional term meaning toward the tail (coccyx in humans).

Frontal Plane (Coronal Plane)

A sectional plane oriented parallel to the long axis that separates anterior and posterior portions of the body.

Sagittal Plane

A sectional plane oriented parallel to the long axis that separates right and left portions of the body.

Midsagittal Section

A sagittal section where the plane passes directly through the midline, separating the body into equal right and left sides.

Parasagittal Section

A sagittal section that misses the midline, separating the body into unequal right and left sides.

Transverse Plane (Horizontal Plane)

A sectional plane oriented perpendicular to the long axis that separates superior and inferior portions of the body.

Body Cavity

A closed, fluid-filled space lined by thin tissue called serous membrane (serosa), within which vital organs are suspended.

Abdominopelvic Quadrants

Four divisions of the abdominopelvic region—Right Upper Quadrant (RUQ), Left Upper Quadrant (LUQ), Right Lower Quadrant (RLQ), and Left Lower Quadrant (LLQ)—used to describe the location of aches, pains, and injuries.

Abdominopelvic 9 Regions

Nine specific divisions of the abdominopelvic area: Right hypochondriac, Epigastric, Left hypochondriac, Right lumbar, Umbilical, Left lumbar, Right inguinal, Hypogastric (pubic), and Left inguinal regions.

Integumentary System

Major organs include skin, hair, sweat glands, and nails. Functions to protect against environmental hazards, help regulate body temperature, and provide sensory information.

Skeletal System

Major organs include bones, cartilages, associated ligaments, and bone marrow. Functions to provide support and protection for other tissues, store calcium and other minerals, and form blood cells.

Muscular System

Major organs include skeletal muscles and associated tendons. Functions to provide movement, protection, and support for other tissues, and generate heat that maintains body temperature.

Nervous System

Major organs include the brain, spinal cord, peripheral nerves, and sense organs. Functions to direct immediate responses to stimuli, coordinate activities of other organ systems, and interpret sensory information.

Endocrine System

Major organs include the pituitary gland, thyroid gland, pancreas, adrenal glands, and gonads. Functions to direct long-term changes, adjust metabolic activity, and control structural and functional changes during development.

Cardiovascular System

Major organs include the heart, blood, and blood vessels. Functions to distribute blood cells, water, nutrients, waste products, oxygen, carbon dioxide, and heat.

Lymphatic System

Major organs include the spleen, thymus, lymphatic vessels, lymph nodes, and tonsils. Functions to defend against infection and disease and return tissue fluids to the bloodstream.

Respiratory System

Major organs include nasal cavities, sinuses, larynx, trachea, bronchi, lungs, and alveoli. Functions to deliver air to alveoli, provide oxygen to the bloodstream, remove carbon dioxide, and produce sounds.

Digestive System

Major organs include teeth, tongue, pharynx, esophagus, stomach, small intestine, large intestine, liver, gallbladder, and pancreas. Functions to process and digest food, absorb nutrients and water, and store energy.

Urinary System

Major organs include kidneys, ureters, urinary bladder, and urethra. Functions to excrete waste products from the blood, control water balance, store urine, and regulate blood ion concentrations and pH.

Male Reproductive System

Major organs include testes, epididymides, ductus deferentia, seminal vesicles, prostate, penis, and scrotum. Functions to produce sex cells (sperm), seminal fluids, and hormones.

Female Reproductive System

Major organs include ovaries, uterine tubes, uterus, vagina, labia, clitoris, and mammary glands. Functions to produce sex cells (oocytes) and hormones, support developing embryo, and provide milk.