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, and not to the healthcare worker’s right side

left

in medical terminology, a reference to the patient’s actual left side, and not to the healthcare worker’s left side

parallel

positioning of two structures that lie in the same plane and are positioned in a way that they are not touching each other

perpendicular

positioning of two structures that are 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

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, and not to the healthcare worker’s right side

left

in medical terminology, a reference to the patient’s actual left side, and not to the healthcare worker’s left side

parallel

positioning of two structures that lie in the same plane and are positioned in a way that they are not touching each other

perpendicular

positioning of two structures that are 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

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

electron

An electron is a negatively charged subatomic particle.

neutron

A neutron is a subatomic particle that is electrically neutral.

proton

A proton is a positively charged subatomic particle, the number of which determine the type of element the atom is.

molecule

A molecule is two or more atoms joined together by sharing electrons.

biomolecules

Biomolecules are molecules that make up living tissue, mostly made up of carbon, hydrogen, and oxygen.

amino acids

Amino acids are organic compounds that are the building blocks of proteins.

carbohydrate

A carbohydrate is a biological dietary compound made of carbon, hydrogen, and oxygen that provides energy for the body.

lipids

Lipids are hydrophobic molecules that store energy and act as structural modules of cell membranes.

Ribonucleic acid (RNA)

Ribonucleic acid transmits the information encoded in DNA to other organelles.

Deoxyribonucleic acid (DNA)

Deoxyribonucleic acid encodes the genetic material of the cell.

chromatin

Chromatin is a combination of DNA and proteins that come together to make up chromosomes before cell division.

Nucleic acid

A nucleic acid is the molecular unit of polymers, such as DNA and RNA, that transmits genetic information.

physiology

Physiology is the branch of biology that deals with the functioning of living organisms.

neurophysiology

Neurophysiology is the study of the function of the nervous system.

receptor

A receptor is a molecule that receives and transmits a signal.

effector

An effector is a muscle, organ, or gland that responds to stimulus on a nerve impulse.

membrane transport

Membrane transport is the movement of molecules across a membrane barrier.

osmosis

Osmosis is the tendency of molecules to diffuse across a membrane, causing equal concentrations on both sides of the membrane.

diffusion

Diffusion is the passive movement of different types of molecules that achieves an equal concentration after being randomly distributed.

hydrophilic

Hydrophilic describes water-loving or water-soluble molecules, such as proteins or carbohydrates, that form hydrogen bonds with water.

hydrophobic

Hydrophobic describes water-hating or water-insoluble molecules, such as fats and lipids, that cannot form hydrogen bonds.

homeostasis

Homeostasis is the ability or tendency of an organism to stabilize its internal environment.

homeostatic imbalance

Homeostatic imbalance is a disturbance in equilibrium due to a disruption in the external environment.

homeostatic regulation

Homeostatic regulation is the process that maintains physiological equilibrium that is controlled through the nervous and endocrine systems.

negative feedback

Negative feedback is a response in the opposite direction of a disruption that can support homeostasis.

positive feedback

Positive feedback is the amplification and stimulation of a response to an external signal.

cell

The cell is the structural and functional unit of living organisms; it is membrane-bound and self-replicating.

organelle

An organelle is a membrane-bound structure in the cell, such as a mitochondrion, a lysosome, or the nucleus, that performs a specific function.

nucleus

The nucleus is the organelle that contains the cell's genetic material.

nucleoli

Nucleoli are structures within the nucleus of a cell where ribosomes are created.

nuclear envelope

A nuclear envelope is a double-layer membrane surrounding the contents of the nucleus.

cytoplasm

Cytoplasm is fluid material that gives support to the cell and can be found between the plasma membrane and the nucleus.

mitochondrion

The mitochondrion is the organelle that processes fats and carbohydrates to release energy.

lysosomes

Lysosomes are organelles that break down waste material in the cell.

peroxisomes

Peroxisomes are organelles that break down cell components and protect cells from toxic materials.

plasma membrane

The plasma membrane is the outer envelope of the cell that acts as a barrier to the external environment, allowing nutrients to enter the cell and waste to leave the cell.

ribosomes

Ribosomes are molecular machines that decode RNA into proteins built from amino acids.

rough endoplasmic reticulum

The rough endoplasmic reticulum is an organelle that works with ribosomes to support protein assembly and transports proteins to other sites in the cell.

smooth endoplasmic reticulum

The smooth endoplasmic reticulum is an organelle that helps fold, modify, and transport new proteins to other sites in the cell.

Golgi apparatus

The Golgi apparatus is an organelle that processes proteins to export them from the cell or to release them into parts of the body.

Anatomical position

the standard way the body is positioned when using anatomical terminology (standing, with feet slightly apart, arms to the side, and the head, eyes, and palms of the hands facing forward)

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

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

anterior

toward the front of the body, or in front of something else

Posterior

toward the back of the body, or in back of something else

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 (typically the point of origin of a limb)

proximal

a point that is closer to a point of reference (typically the point of origin of a limb)

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 healthcare workers use to refer to specific parts, or regions, of the body

Axial Region

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

Cephalic Region

body region that pertains to the head, including the eyes, brain, jaw, ears, cheek, nose, mouth and chin

Cervical Region

the area of the body pertaining to the neck

Trunk Region

also called the torso, the region of the body that includes the chest and abdomen

Thoracic Region

body region that pertains to the chest, and extends from the neck to the diaphragm

Abdominal region

body region below the torso that extends from the diaphragm to (and including) the pelvis

Pelvic Region

the lower abdomen region that connects the torso and the legs and also contains the reproductive organs

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 as they relate to internal structures

Superficial Landmark

a structure on the surface of the body that helps orient an observer

Midclavicular Line

invisible vertical line that passes through the midpoint of the clavicle (collarbone)

Midpupillary Line

an invisible vertical line that passes through the midpoint of the eye

Thyroid Cartilage

the largest cartilage in the larynx (voice box); it protects the vocal cords

Upper Extremities

upper area of the human body that includes the shoulder, forearm, elbow, arm, wrist, and hand

Axilla

area on the body located directly under the joint where the arm connects to the shoulder, also called the armpit

Carpal

referring to the bones of the wrist

Lower Extremities

lower area of the human body that includes the hips, thighs, knees, lower legs, ankles, and feet

Plantar

the bottom area of the foot that is in contact with the ground when standing

pancreas

organ that secretes fluid into the small intestine

liver

largest organ that filters unsafe material from the blood

kidney

organ that filters blood and removes waste

ducts

tubes in the body that carry fluids secreted by glands

glands

organs that secrete specific chemical substances for use in the body or elimination

thymus gland

a glandular organ in the upper chest cavity that produces T-cells

spleen

organ located on the left side of the abdomen that filters, stores, and destroys blood cells

lymph nodes

small bean-shaped glands that produce lymphocytes and filter lymph

bones

hard structures that create the frame of the body

cartilage

flexible connective tissue found in many areas of the human body

ligaments

a band of tissue that connects bones or cartilage

muscles

tissues that contract to help move different parts of the body

tendons

strong tissues that connects muscle to bone

ureter

muscular ducts that carry urine from the kidneys to the bladder

testes

male reproductive glands that produce sperm

penis

external organ of a male used in the process of discharging semen and urine

ovaries

female reproductive organs that generate eggs

uterus

hollow, pear-shaped organ in the pelvic cavity of the female human body

vagina

elastic, lubricated muscular canal that connects the cervix of the womb to the vulva

bladder

organ that stores liquid or gas