Anatomy Final Definitions

Histology

the study of tissues

Selective permeability

the ability to let certain materials in or out while restricting others

Physiology

the study of the functions of an organism and its parts

Organs

a group of tissues specialized for a particular function

Endocytosis

the process by which large molecules are taken into the cell

Endocrine glands

ductless glands that secrete hormones into the bloodstream

Stromal cells

cells that provide structure or support for parenchymal cells

Fibroblasts

spindle-shaped cells that form connective tissue

Chondrocytes

mature cartilage cells

Labile

cells that undergo mitosis regularly and quickly

Cancellous bone

bone with many small spaces or cavities surrounding the bone matrix

Process

a projection on a bone

Hematopoiesis

a process of manufacturing blood cells

Suture

a junction between the bones of the skull

Axial skeleton

the portion of the skeleton that supports and protects the head, neck, and trunk

Osteoblast

a bone-forming cell

Callus

a mass of tissue that connects the ends of a broken bone

Osteoclasts

a large, multinucleated cell that breaks down bone

Osteocytes

a mature bone cell surrounded by a matrix

Hemotoma

a mass of blood that is confined to some limited space

Sarcomere

a repeating unit of a myofibril

Muscle tone

the state of partial contraction in a muscle, even when the muscle is not being used

Motor unit

one motor neuron and all the muscle fibers it innervates

Origin

the point at which a muscle’s tendon attaches to the more stationary bone

Mastication

the process of chewing

Nerves

bundles of neuron and exons and their coverings, which are found outside the CNS

Ganglia

collections of neuron cell bodies that are found outside the CNS

Spinal nerves

nerves that originate from the spinal chord

Cranial nerves

nerves that originate from the brain

Afferent neurons

neurons that transmit action potentials from the sensory organs to the CNS

Efferent neurons

neurons that transmit action potentials from CNS to the effector organs

Somatic motor nervous system

PNS neurons that transmit action potentials from the CNS to skeletal muscles

Autonomic nervous system

PNS nervous system that transmit action potentials from the CNS to smooth muscles, cardiac muscles, and glands

Sympathetic divison

division of the ANS that generally prepares the body for increased energy expenditure

Parasympathetic division

division of the ANS that regulates resting and nutrion-related functions such as digestion, defecation, and nutrition

Association neuron

a neuron that conducts action potentials from one neuron to another neuron within the CNS

Excitability

the ability to undergo an action potential in response to a stimulus

Potential difference

a measure of the charge difference across the cell membrane

Gray matter

collections of neuron cell bodies and their associated neurologia

White matter

bundles of parallel axons and their coverings

Decussation

the anatomical crossing over of neurons from left to right

Vital functions

those functions of the body necessary for life

Sensory receptor

an organ that responds to a specific type of stimulus by triggering an action potential on a sensory neuron

Somatic receptors

sensory receptors in the skin, muscle, and tendons

Visceral receptors

sensory receptors in the internal organs

Special receptors

sensory receptors in specific locations

Mechanoreceptors

sensory receptors that respond to movement whether it is light touch, vibration, or pressure

Thermoreceptors

sensory receptors that respond to hear or cold

Photoreceptors

sensory receptors that respond to light

Chemoreceptors

sensory receptors that respond to chemicals

Nociceptors

sensory receptors that respond to several types of excess stimulation, which is termed pain

Cutaneous receptors

receptors in the skin

Proprioceptors

receptors in the skeletal muscles and tendons

Viscosity

the resistance to flow and alteration of shape due to cohesion

Plasma

the fluid part of the blood which is mostly water (55% by volume)

Formed elements of blood

the red blood cells, white blood cells, and cell fragments called platelets, about 45% by volume

Erythrocytes

red blood cells that carry the O2 in blood

Leukocytes

white blood cells that perform defense functions in blood

Platelets

remaining 5% of formed elements in blood (leukocytes)

Diapedesis

passage of any formed elements of blood through the blood vessel and into the tissue spaces

Chemotaxis

attraction of cells to chemical stimuli

Hemopoiesis

the process by which the formed elements of blood are made in the body

Hemostasis

process by which the body stops blood loss

Coagulation factors

proteins in the blood plasma which helps initiate the blood coagulation process

Antigen

protein or carbohydrate that when introduced in the blood triggers the production of an antibody

Arteries

blood vessels that carry blood away from the heart

Capillaries

tiny, thin-walled blood vessels that allow that exchange of gases and nutrients between blood and cells

Veins

blood vessels that carry blood back to the heart

Pulmonary circulation

circulation of the blood over the air sacs of the lungs

Systemic circulation

circulation of the blood through the other tissues of the body

Systolic phase

phase of the cardiac cycle in which ventricles contract

Diastolic phase

phase of the cardiac cycle in which ventricles relax

Cardiac cycle

one complete round of systole and diastole

Arterioles

smallest arteries that have 3 tunics

Venules

small veins that do not have 3 tunics but instead have only an endothelium, basement membrane, and a few smooth muscle cells

Lymphatic tissue

groups of lymphocytes and macrophages that provide immune protection

Lymph nodes

encapsulated masses of lymphatic tissue found along lymph vessels

Lymph

watery liquid formed from interstitial fluid and found in lymph vessels

Edema

a buildup of excess interstitial fluid in the tissues, which leads to swelling

Immunological defense

the process by which the body protects itself from pathogenic invaders such as bacteria, fungi, parasites, and foreign substances

Mucose-associated lymphoid tissue (MALT)

concentrations of lymphatic tissue without a connective tissue capsule

Lymph nodules

lymphatic tissue arranged into compact, somewhat spherical structures, but without a capsule

Innate immunity

an immune response that is the same regardless of the pathogen or toxin encountered

Acquired immunity

an immune response targeted at a specific pathogen or toxin after exposure

Complement

a series of multiple plasma proteins activated by foreign cells or antibodies to those cells; they lyse bacteria, promote phagocytosis, and promote inflammation

Interferon

proteins secreted by cells infected with a virus; these proteins do not save the infected cell, but they stimulate nearby cells to strengthen themselves against a viral invasion

Pyrogens

chemicals that promote fever by acting on the hypothalamus

Humoral immunity

acquired immunity provided by antibodies in the blood plasma

Cell-mediated immunity

acquired immunity provided by T lymphocytes

Digestion

the breakdown of food molecules into their individual components

Deglution

the act of swallowing

Peristalsis

the process of concentration and relaxation of circular smooth muscle that pushes food through the alimentary canal

Gastric juice

the acidic secretions of the stomach

Adventitia

a thin layer of loose connective tissue that binds an organ to surrounding tissues or organs

Lumen

the space in the center of a tube

Macronutrients

the nutrients the body needs in large amounts: carbohydrates, fats, and proteins

Micronutrients

the nutrients the body needs in small amounts such as vitamins and minerals

Upper respiratory system

the part of the respiratory system that contains the nasal cavity, paranasal sinuses, and pharynx

Lower respiratory system

the part of the respiratory system that contains the larynx, trachea, bronchi, and lungs

Ventilation

the process of getting air into the lungs and back