Anatomy Review: Levels of Organization, Body Systems, Homeostasis, and Terminology

Vocabulary practice flashcards covering structural levels of organization, the 11 organ systems, homeostatic mechanisms, directional terms, anatomical body planes and cavities, serous membrane layers, medical prefixes/suffixes, and anatomical landmarks.

Hierarchy of structural organization

The pyramid of complexity in the human body proceeding from chemical level, cellular level, tissue level, organ level, organ system level, to organismal level.

Chemical level

The structural level where atoms bond together to form molecules with three-dimensional structures.

Cellular level

The level of organization where a variety of molecules combine to form the fluid and organelles of a body cell.

Tissue level

A level of organization consisting of a community of similar cells that form a body tissue.

Organ level

A level of organization where two or more different tissues combine to form an organ.

Organ system level

A level of organization in which two or more organs work closely together to perform the functions of a body system.

Organismal level

The highest level of structural organization where many organ systems work harmoniously together to perform the functions of an independent organism.

Integumentary system

Consists of hair, skin, and nails; encloses internal body structures and serves as the site of many sensory receptors.

Muscular system

Consists of skeletal muscles and tendons; enables movement (along with the skeletal system) and helps maintain body temperature.

Skeletal system

Consists of cartilage, bones, and joints; supports the body and enables movement (along with the muscular system).

Endocrine system

Consists of the pituitary gland, thyroid gland, pancreas, adrenal glands, testes, and ovaries; secretes hormones and regulates bodily processes.

Nervous system

Consists of the brain, spinal cord, and peripheral nerves; detects and processes sensory info, and activates bodily processes.

Cardiovascular system

Consists of the heart and blood vessels; delivers oxygen and nutrients to tissues and equalizes temperature in the body.

Lymphatic system

Consists of the thymus, lymph nodes, spleen, and lymphatic vessels; returns fluid to blood and defends against pathogens.

Respiratory system

Consists of the nasal passage, trachea, and lungs; removes carbon dioxide from the body and delivers oxygen to blood.

Digestive system

Consists of the stomach, liver, gall bladder, large intestine, and small intestine; processes food for use by the body and removes wastes from undigested food.

Urinary system

Consists of the kidneys and urinary bladder; controls water balance in the body, removes wastes from blood, and excretes them.

Male reproductive system

Consists of the epididymis and testes; produces sex hormones and gametes, and delivers gametes to the female.

Female reproductive system

Consists of mammary glands, ovaries, and uterus; produces sex hormones and gametes, supports embryo/fetus until birth, and produces milk for infant.

Homeostasis

The state of steady internal conditions maintained by living things.

Negative feedback

A mechanism that reverses a deviation from the set point to return conditions back to normal, such as body temperature regulation exceeding $37^\circ\text{C}$.

Positive feedback

A physiological mechanism that intensifies a change in the body's physiological condition rather than reversing it (e.g., child birth).

Receptor (Sensor)

A component in a feedback mechanism that detects a change or stimulus.

Control center

A component in a feedback mechanism that receives input from the sensor and activates the effector.

Effector

A component in a feedback mechanism that carries out the response to reverse the change and bring conditions back to normal.

Directional terms

Standard paired terms used to describe the relative positions of structures on the human body in anatomical position.

Anterior (Ventral)

Describes the front or direction toward the front of the body (e.g., toes are anterior).

Posterior (Dorsal)

Describes the back or direction toward the back of the body.

Superior (Cranial)

Describes a position above or higher than another part of the body (e.g., eyes are superior to the mouth).

Inferior (Caudal)

Describes a position below or lower than another part of the body, towards the feet (e.g., pelvis is inferior to the abdomen).

Lateral

Describes the side or direction toward the side of the body (e.g., eyes are lateral to the nose).

Medial

Describes the middle or direction toward the middle of the body (e.g., the nose is medial to the eyes).

Proximal

Describes a position nearer to the point of attachment or trunk of the body (e.g., the elbow is proximal to the wrist).

Distal

Describes a position farther from the point of attachment (e.g., the ankle is distal to the knee).

Superficial

Describes a position closer to the surface of the body (e.g., skin is superficial to the bones).

Deep

Describes a position farther from the surface of the body (e.g., the brain is deep to the skull).

Anatomical planes

Imaginary two-dimensional slices through the body, including sagittal, frontal (coronal), transverse, and oblique planes.

Body cavities

Internal fluid-filled spaces containing organs, divided primarily into the dorsal body cavity (cranial and vertebral) and ventral body cavity (thoracic and abdominopelvic).

Abdominopelvic regions and quadrants

Divisions of the abdominopelvic area used for anatomical referencing, consisting of nine distinct regions or four quadrants (RUQ, LUQ, RLQ, LLQ).

Parietal layer

The layer of a serous membrane that lines the walls of the body cavity (pariet- refers to a cavity wall).

Visceral layer

The layer of a serous membrane that directly covers the organs (the viscera).

Serous membrane layers

Double-layered membranes where the outer parietal layer lines cavity walls and the inner visceral layer covers organs, separated by a fluid cavity (analogous to a fist pushing into a balloon).

-itis

Medical suffix indicating inflammation (e.g., arthritis).

-ectomy

Medical suffix indicating surgical removal (e.g., appendectomy).

-ology

Medical suffix indicating the study of (e.g., cardiology).

-algia

Medical suffix indicating pain (e.g., neuralgia).

-megaly

Medical suffix indicating enlargement (e.g., cardiomegaly).

-emia

Medical suffix indicating a blood condition (e.g., anemia).

Hyper-

Medical prefix indicating above normal or excessive (e.g., hypertension).

Hypo-

Medical prefix indicating below normal or deficient (e.g., hypoglycemia).

Brady-

Medical prefix indicating slow (e.g., bradycardia).

Tachy-

Medical prefix indicating fast or rapid (e.g., tachycardia).

Cardi/o

Medical root/combining form referring to the heart (e.g., cardiology).

Neur/o

Medical root/combining form referring to a nerve (e.g., neurology).

Hepat/o

Medical root/combining form referring to the liver (e.g., hepatitis).

Nephr/o

Medical root/combining form referring to the kidney (e.g., nephrology).

Oste/o

Medical root/combining form referring to bone (e.g., osteoporosis).

Anatomical landmarks

Standard regional terms used to specify distinct exterior locations across anterior and posterior surfaces of the human body.

Cephalon

Anatomical region referring to the head (cephalic).

Cervicis

Anatomical region referring to the neck (cervical).

Thoracis

Anatomical region referring to the chest or thorax (thoracic).

Brachium

Anatomical region referring to the arm (brachial).

Antebrachium

Anatomical region referring to the forearm (antebrachial).

Carpus

Anatomical region referring to the wrist (carpal).

Manus

Anatomical region referring to the hand (manual).

Lumbus

Anatomical region referring to the loin or lower back (lumbar).

Gluteus

Anatomical region referring to the buttock (gluteal).

Femur

Anatomical region referring to the thigh (femoral).

Patella

Anatomical region referring to the kneecap (patellar).

Crus

Anatomical region referring to the leg (crural).

Sura

Anatomical region referring to the calf (sural).

Pes

Anatomical region referring to the foot (pedal).

Planta

Anatomical region referring to the sole of the foot (plantar).

Inguen

Anatomical region referring to the groin (inguinal).

Axilla

Anatomical landmark referring to the armpit (axillary).

Olecranon

Anatomical landmark referring to the back of the elbow (olecranal).

Popliteus

Anatomical landmark referring to the back of the knee (popliteal).