Human Anatomy and Cell Structure: Systems, Tissues, and Bone Details

ANATOMY

The study of internal and external structures of the human body.

MICROSCOPIC ANATOMY

The study of body structures that cannot be viewed without magnification; includes cytology and histology.

GROSS ANATOMY

The study of body structures which are visible without the aid of magnification.

DEVELOPMENTAL ANATOMY

The study of structural changes that occur from conception to physical maturity.

COMPARATIVE ANATOMY

The study of the anatomy of different types of animals.

PATHOLOGICAL ANATOMY

The study of structural changes in cells, tissues, and organs caused by disease.

RADIOGRAPHIC ANATOMY

The study of internal body structures by using noninvasive imaging techniques, such as X-ray imaging and ultrasound.

SURGICAL ANATOMY

The study of anatomical landmarks, which are important to surgical procedures.

CHEMICAL LEVEL

Atoms combine to form small molecules and larger macromolecules; chemicals comprise the entire body.

CELLULAR LEVEL

Cells are comprised of molecules; they are the smallest living units in the body.

TISSUE LEVEL

Similar types of cells, with a common function, combine to form tissues.

ORGAN LEVEL

More than one tissue type combines to form organs; complex physiological processes occur at this level.

ORGAN SYSTEM LEVEL

Organs that work closely together combine to form an organ system to accomplish a common purpose.

HUMAN ORGANISM

The highest level of structural organization; the combination of all the organ systems functioning together.

Cytology

The study of cells.

Histology

The study of tissues.

Surface Anatomy

The study of shapes and markings on the body surface.

Regional Anatomy

The study of all structures in a single body region, superficial or deep.

Systemic Anatomy

The study of all organs with related functions, i.e., study one organ system at a time.

Embryology

The study of structural formation and development before birth.

Organ Systems

There are 11 organ systems of the human body.

Integumentary System

Forms the cutaneous membrane (epidermis and dermis), the external body covering; provides protection and thermoregulation; synthesizes vitamin D; provides cutaneous reception through sensory receptors; additional accessory structures are hair follicles, nails, sweat (sudoriferous) glands and oil (sebaceous) glands.

Skeletal System

Provides protection and support to the body organs; provides skeletal framework for the muscles to attach, hence, causing movement; stores minerals; blood cell formation occurs within bones.

Muscular System

Produces motion; maintains posture by providing support; produces heat.

Nervous System

Control center of the body, which directs immediate responses to stimuli and coordinates the other organ systems; responds to internal and external stimuli by activating appropriate muscles and glands.

Endocrine System

Comprised of glands, which secrete hormones that regulate processes (such as metabolism, growth, and reproduction) of the other organ systems.

Cardiovascular System

Comprised of the heart, blood vessels, and blood to transport materials (such as respiratory gases, nutrients and wastes) within the body.

Lymphoid (Lymphatic and Immune) System

Comprised of the lymphatic vessels, lymphoid organs (lymph nodes, the thymus, and the spleen), lymphocytes, and lymphoid tissue; returns leaked fluid to blood; provides defense against pathogens and disease by housing white blood cells (lymphocytes) that function in immunity.

Respiratory System

Comprised of the nasal cavities, pharynx, larynx, trachea, bronchi, and the lungs; maintains the blood's constant supply of oxygen and removal of carbon dioxide by delivering air to the lungs where gas exchange occurs at the alveoli (air sacs of the lungs).

Digestive System

Comprised of the gastrointestinal tract (or alimentary canal) and accessory structures, which together function to process food and absorb nutrients.

Urinary System

Comprised of the kidneys, ureters, the urinary bladder, and the urethra; functions to eliminate excess water, salts, and nitrogenous wastes from the body; regulates water, electrolyte, and acid-base balance of the blood.

Reproductive System

Comprised of gonads (testes in the male; ovaries in the female), accessory organs and external genitalia; overall function is to produce sex cells and hormones for the purpose of producing offspring; the female reproductive system supports embryonic development.

Anatomical Position

In anatomical position, the person is standing upright, arms at sides, palms facing forward (little fingers are medial, touching the thighs), feet flat on the floor, face straight ahead.

Axial Region

Consists of the head, neck and torso.

Appendicular Region

Consists of the upper and lower limbs (or extremities).

SUPERIOR (cranial or cephalic)

above the point of reference; toward the head end or upper part of a structure or the body

INFERIOR (caudal)

below the point of reference; toward the tail end or toward the lower part of a structure or the body

ANTERIOR (ventral)

toward or at the front of the body; in front of; (the front or belly side)

POSTERIOR (dorsal)

toward or at the back of the body; behind; (the back side)

MEDIAL

toward or at the midline of the body; on the inner side of (e.g. The trachea is medial to the arm.)

LATERAL

away from the midline of the body; toward the sides or on the outer sides of (e.g. The ears are lateral to the nose.)

PROXIMAL

closer to the origin of the body part or the point of attachment of a limb to the body trunk (e.g. The shoulders are proximal to the elbows.)

DISTAL

away from the origin of a body part or the point of attachment of a limb to the body trunk (e.g. The fingers are distal to the wrist.)

SUPERFICIAL (external)

closer to or at the body surface (e.g. The skin is superficial to the heart.)

DEEP (internal)

farther from or away from the body surface; more internal (e.g. The lungs are deep to the skin.)

IPSILATERAL

on the same side (e.g. The right arm and right leg are ipsilateral.)

CONTRALATERAL

on opposite sides (e.g. The right arm and left leg are contralateral.)

CEPHALON (cephalic)

area of the head

CERVICIS (cervical)

neck region

THORACIS (thoracic)

chest region

BRACHIUM (brachial)

upper arm

ANTEBRACHIUM (antebrachial)

forearm

CARPUS (carpal)

wrist

MANUS (manual)

hand

POLLICIS (pollex)

thumb

ABDOMEN (abdominal)

abdominal region

UMBILICUS (umbilical)

navel or bellybutton

PELVIS (pelvic)

pelvic region

PUBIS (pubic)

anterior pelvis or genital region

INGUEN (inguinal)

groin

LUMBUS (lumbar)

lower back

GLUTEUS (gluteal)

buttock region

FEMUR (femoral)

thigh

PATELLA (patellar)

kneecap

CRUS (crural)

anterior leg, from knee to ankle

SURA (sural)

posterior, calf of leg

TARSUS (tarsal)

ankle

PES (pedal)

foot (pedals of a bike)

PLANTA (plantar)

the bottom of the foot, sole

HALLUCIS (hallux)

great toe or big toe

FRONTAL (CORONAL) plane

lies vertically and divides the body into an anterior (front) portion and a posterior (back) portion

TRANSVERSE (HORIZONTAL) plane

lies horizontally and divides the body into a superior (top) portion and an inferior (lower) portion. These sections are also called cross sections.

SAGITTAL plane

lies vertically and divides the body into a right portion and a left portion.

MIDSAGITTAL PLANE (MEDIAN PLANE)

if the sagittal plane lies exactly in the midline and the portions are equivalent

PARASAGITTAL PLANES

all other sagittal planes that are offset from the midline and result in unequal portions

DORSAL body cavity

includes cranial cavity and spinal cavity

Cranial cavity

lies within skull (cranium), encasing the brain

Spinal cavity

lies within the vertebral column, enclosing the spinal cord

VENTRAL body cavity (COELOM)

provides protection, allows organ movement, lining prevents friction

THORACIC cavity

Superior to diaphragm, contains heart, lungs, blood vessels; surrounded by the ribs and the muscles of the chest wall.

PLEURAL CAVITIES

Right and left cavities, which enclose the right and left lungs.

parietal pleura

The thin membrane that lines the chest walls of the serous membrane.

visceral pleura

The thin membrane that adheres to the lungs of the serous membrane.

serous fluid

Fills the pleural cavity between the layers of the serous membrane.

MEDIASTINAL CAVITY

A central cavity containing a band of organs, which lies between the pleural cavities; contains the heart, esophagus, trachea, and major blood vessels.

PERICARDIAL CAVITY

Contains the heart.

parietal pericardium

The thin membrane that lines the pericardial walls of the serous membrane.

visceral pericardium

The thin membrane that adheres to the heart surface of the serous membrane.

ABDOMINOPELVIC CAVITY

Lies inferior to the diaphragm and is divided into a superior part and an inferior part.

ABDOMINAL cavity

The superior part, which contains the liver, stomach, small intestine, spleen, kidneys, and other organs; extends from diaphragm superiorly to superior border of sacrum.

peritoneum

Serous membrane surrounding many organs in the abdominopelvic cavity.

parietal peritoneum

The thin membrane that lines the wall of the serous membrane.

visceral peritoneum

The thin membrane that adheres to the abdominopelvic organs of the serous membrane.

retroperitoneal

Refers to organs located behind the abdominopelvic cavity, such as the kidneys, adrenal glands, pancreas, and ureters.

PELVIC cavity

The inferior part, which is enclosed by the bony pelvis; contains the urinary bladder, some reproductive organs, and the rectum.

abdominopelvic quadrants

Four segments created by drawing one horizontal plane and one vertical plane through the umbilicus.

Right upper quadrant (RUQ)

One of the four abdominopelvic quadrants.

Right lower quadrant (RLQ)

One of the four abdominopelvic quadrants.

Left upper quadrant (LUQ)

One of the four abdominopelvic quadrants.

Left lower quadrant (LLQ)

One of the four abdominopelvic quadrants.