Anatomy and Physiology

plane

A two-dimensional surface that divides two halves.

vertical

Oriented vertically up or down where the frontal and sagittal planes meet.

sagittal

A plane that divides the body into left and right sections.

frontal

A plane that divides the body into front and back sections.

transverse

A plane that divides the body into top and bottom sections.

anteroposterior

The axis that extends from posterior to anterior.

axis

A line between two points.

bilateral symmetry

Anatomical parts that are the same on both sides of a plane.

symmetry

Matching form and configuration on opposite sides of a plane.

directional term

A term used to explain the relation of one or more body parts.

caudal

Directional term for near the posterior end of the body.

medial

Directional term for situated toward the midline of the body.

distal

Directional term for farther from the origin of the body part point of attachment.

proximal

Closer to the origin of the body part point of attachment.

lateral

Located away from the midline of the body off to the side.

intermediate

Located between a medial and lateral structure.

deep

Extending beneath the body surface.

superficial

Located near or toward the body surface.

right

In medical terminology, a reference to the patient’s actual right side.

left

In medical terminology, a reference to the patient’s actual left side.

parallel

Positioning of two structures that lie in the same plane and are not touching.

perpendicular

Positioning of two structures at a right angle to each other.

cranial

Related to the upper part of the head or skull.

inferior

Anatomy located away from the head or toward the lower body.

superior

Anatomy located toward the head or upper part of the body.

dorsal

Positioned toward the back of the body.

ventral

Positioned towards the front, or abdominal side, of the body.

atoms

Atoms are the building blocks of molecules.

subatomic particles

Particles that are smaller than the atom, such as protons, neutrons, and electrons.

electron

A negatively charged subatomic particle.

neutron

A subatomic particle that is electrically neutral.

proton

A positively charged subatomic particle that determines the type of element.

molecule

Two or more atoms joined together by sharing electrons.

biomolecules

Molecules that make up living tissue, mostly made of carbon, hydrogen, and oxygen.

amino acids

Organic compounds that are the building blocks of proteins.

carbohydrate

A dietary compound made of carbon, hydrogen, and oxygen that provides energy.

lipids

Hydrophobic molecules that store energy and act as structural modules of cell membranes.

Ribonucleic acid (RNA)

Transmits the information encoded in DNA.

Deoxyribonucleic acid (DNA)

Encodes the genetic material of the cell.

chromatin

A combination of DNA and proteins that make up chromosomes.

Nucleic acid

Molecular units of polymers, such as DNA and RNA, that transmit genetic information.

physiology

The branch of biology that deals with the functioning of living organisms.

neurophysiology

The study of the function of the nervous system.

receptor

A molecule that receives and transmits a signal.

effector

A muscle, organ, or gland that responds to a stimulus.

membrane transport

The movement of molecules across a membrane barrier.

osmosis

The tendency of molecules to diffuse across a membrane.

diffusion

The passive movement of different types of molecules to achieve equal concentration.

hydrophilic

Describes water-loving molecules that form hydrogen bonds with water.

hydrophobic

Describes water-hating molecules that cannot form hydrogen bonds.

homeostasis

The ability of an organism to stabilize its internal environment.

homeostatic imbalance

A disturbance in equilibrium due to a disruption in the environment.

homeostatic regulation

The process that maintains physiological equilibrium.

negative feedback

A response in the opposite direction of a disruption.

positive feedback

The amplification of a response to an external signal.

cell

The structural and functional unit of living organisms.

organelle

A membrane-bound structure in the cell that performs a specific function.

nucleus

The organelle that contains the cell's genetic material.

nucleoli

Structures within the nucleus where ribosomes are created.

nuclear envelope

A double-layer membrane surrounding the nucleus.

cytoplasm

Fluid material that gives support to the cell.

mitochondrion

The organelle that processes fats and carbohydrates to release energy.

lysosomes

Organelles that break down waste material in the cell.

peroxisomes

Organelles that break down cell components and protect from toxins.

plasma membrane

The outer envelope of the cell that acts as a barrier.

ribosomes

Molecular machines that decode RNA into proteins.

rough endoplasmic reticulum

An organelle that supports protein assembly and transport.

smooth endoplasmic reticulum

An organelle that helps fold, modify, and transport proteins.

Golgi apparatus

An organelle that processes proteins to export from the cell.

Anatomical position

The standard positioning of the body when using anatomical terminology.

Sagittal plane

A vertical plane that divides the body into left and right halves.

Coronal plane

A vertical plane that divides the body into front and back halves.

axis

An invisible line that runs vertically through the center of the axial region.

anterior

Toward the front of the body.

Posterior

Toward the back of the body.

lateral

Describes something that is away from the midline of the body.

medial

Refers to something that is toward the midline of the body.

distal

A point that is farther away from a point of reference.

proximal

A point that is closer to a point of reference.

superior

A body structure that is located above another structure.

inferior

A body structure that is located below another structure.

Regional terminology

A set of vocabulary words that refer to specific parts of the body.

Axial Region

The body region that includes the head, neck, and trunk.

Cephalic Region

Body region that pertains to the head.

Cervical Region

The area of the body pertaining to the neck.

Trunk Region

The region of the body that includes the chest and abdomen.

Thoracic Region

Body region that pertains to the chest.

Abdominal region

Body region below the torso between the diaphragm and pelvis.

Pelvic Region

The lower abdomen region that connects the torso and the legs.

Vertebral Region

The central region of the back parallel to the vertebral column.

Appendicular Region

The body region that includes the arms and legs.

Surface Anatomy

The study of external configurations of the body.

Superficial Landmark

A structure on the surface of the body that helps orient an observer.

Midclavicular Line

An invisible vertical line that passes through the midpoint of the clavicle.

Midpupillary Line

An invisible vertical line that passes through the midpoint of the eye.

Thyroid Cartilage

The largest cartilage in the larynx that protects the vocal cords.

Upper Extremities

The upper area of the body that includes the shoulder and arms.

Axilla

Area on the body located under the joint where the arm connects to the shoulder.

Carpal

Referring to the bones of the wrist.

Lower Extremities

The lower area of the body that includes the hips and legs.