Anatomy and Physiology Terms
Intro. to Anatomy and Physiology
Anatomy• Branch of science dealing with
the form and structure of body parts.
Physiology • Branch of science that studies
body functions.
Appendicular• Upper and lower limbs
Axial• Head, neck, and trunk
Homeostasis • State of equilibrium in which
the internal environment of the body remains at a normal range.
Cellular Metabolism
Anabolism • Synthesis of larger molecules
from smaller molecules.
Synthesis • Building large molecules from
smaller ones.
Catabolism • Breakdown of larger molecules
into smaller ones.
Decomposition • The breakdown of molecules
into simpler compounds.
Oxidation • Process by which oxygen is
combined with another chemical.
Enzyme • Protein that catalyzes a
specific biochemical reaction.
Substrate • Target of enzyme action.
Organic • Carbon-containing molecules.
Inorganic • Chemical substances that lack
carbon and hydrogen.
Ion • Atom or molecule with an
electric charge.
Lipid • Fat, oil, or fatlike compound
that usually has fatty acids in its molecular structure.
Nucleic Acid • Substance composed of
boded nucleotides; RNA or DNA.
Cytoplasm • The contents of a cell
excluding the nucleus and cell membrane.
Organelle • Part of a cell that performs a
specialized function.
Nucleus • Cellular organelle enclosed by
a double-layer, porous membrane and containing DNA.
Differentiation • Cell specialization
Diffusion • Random movement of
molecules from a region of higher concentration toward one of lower concentration.
Facilitated Diffusion • Diffusion in which a carrier
molecule transports a substance across a cell membrane from a region of higher concentration to a region of lower concentration.
Active Transport • Process that requires energy
to move a substance across a cell membrane, usually against the concentration gradient.
Osmosis • Diffusion of water through a
selectively permeable membrane in response to a concentration gradient.
Equilibrium • State of balance between two
opposing forces.
Endocytosis • Physiological process by
which a cell membrane envelopes a substance and draws it into the cell in a vesicle.
Exocytosis • Transport of a substance out
of a cell in a membrane-bound vesicle.
Phagocytosis • Process by which a cell
engulfs and digests solids.
Pinocytosis • Process by which a cell
engulfs droplets of fluid from its surroundings.
Mitosis • Division of a somatic cell (body
cell) to form two genetically identical cells.
Meiosis • Cell division that halves the
genetic material, resulting in egg and sperm cells (gametes).
Epithelial Tissue • One of the basic types of
tissue that covers all free body surfaces.
Connective Tissue • Basic type of tissue that
consists of cells within an extracellular matrix, including bone, cartilage, blood, loose and fibrous connective tissue.
Adipose Tissue • Fat storing tissue.
Cartilage • Type of connective tissue in
which cells are located in the lacunae and are separated by a semisolid extracellular matrix.
Nervous Tissue • Neurons and neuroglial cells
composing the brain, spinal cord, and nerves.
Integumentary • Pertaining to the skin and its
accessory organs.
Epidermis • Outer epithelial layer of skin.
Dermis • The thick layer of skin beneath
the epidermis.
Subcutaneous Layer • Layer of tissue that is mostly
fat and beneath the skin; hypodermis.
Sebaceous Gland • Skin gland that secretes
sebum (oil).
Sweat Gland • Exocrine gland in skin that
secretes a mixture of water, salt, urea, and other bodily fluids.
Melanin • Dark pigment found in the skin
and hair.
Keratinization • Process by which cells form
fibrils of keratin and harden.
Arrector Pili Muscle • Smooth muscle in the skin
associated with a hair follicle (goose bumps).
Spongy Bone • Bone that consists of bars and
plates separated by irregular spaces; cancellous bone.
Compact Bone • Dense tissue in which cells are
arranged in osteons with no apparent spaces.
Diaphysis • Shaft of the long bone.
Epiphysis • End of a long bone.
Periosteum • Fibrous connective tissue
covering the surface of the bone.
Medullary Cavity • Cavity containing marrow
within the diaphysis of a long bone.
Marrow • Connective tissue that
occupies space within bones that includes stem cells.
Articular Cartilage • Hyaline cartilage that covers
the ends of bones in synovial joints.
Intramembraneous Bone
• Bone that forms from membrane-like layers of primitive connective tissue.
Endochondral Bone • Bone that begins as hyaline
cartilage that is subsequently replaced by bone tissue.
Osteocyte • Mature bone cell.
Synovial Joint • Feely movable joint.
Synovial Fluid • Fluid that they synovial
membrane secretes.
Synovial Membrane • Membrane that forms the inner
lining of a freely moveable joint.
Actin • A protein in a muscle fiber that
forms filaments that slide between filaments of the protein myosin, contracting muscle fibers.
Myosin • A protein that, with actin,
contracts and relaxes muscle fibers.
Sarcomere • Structural and functional unit
of a myofibril.
Neurotransmitter • Chemical that an axon end
secretes to stimulate a muscle fiber to contract or a neuron to fire an impluse.
Neuron • Nerve cell
Neuroglial Cell • Specialized cell of the nervous
system that produces myelin, communicates between cells, and maintains the ionic environment, as well as provides other functions.
Soma • Body of the neuron that
contains the nucleus.
Axon • A nerve fiber; conducts a
nerve impulse away from a neuron.
Dendrite • Process of a neuron that
receives input from other neurons.
Meninges • Membrane that covers the
brain and spinal cord.
Synapse • Functional connection
between the axon of one neuron and the dendrite or cell body of another neuron or the membrane of another cell type.
Reflex • Rapid, automatic response to
a stimulus.
Action Potential • Sequence of electrical
changes that occurs in a portion of a nerve cell membrane that is exposed to a stimulus that exceeds the membrane’s threshold.
Sclera • White fibrous outer layer of the
eyeball.
Cornea • Transparent anterior portion of
the outer layer of the eye wall.
Retina • Inner layer of the eye wall that
contains the visual receptors.
Rods • Type of light receptor that
provides colorless vision.
Cones • Color receptor in the retina of
the eye.
Cochlea • Portion of the inner ear that
has hearing receptors.
Hormone • Substance secreted by an
endocrine gland and transported in the blood.
Target Cell • Cell with specific receptors on
which a hormone exerts its effect.
Cardiovascular System and Blood
Atrium • Chamber of the heart that
receives blood from veins.
Ventricle • Cavity, such as brain
ventricles filled with cerebrospinal fluid, or heart ventricles that contain blood.
Arteriole • Small branch of an artery that
communicates with a capillary network.
Capillary • A small blood vessel that
connects an arteriole and a venule.
Venule • Vessel that carries blood from
capillaries to a vein.
Plasma • Fluid portion of circulating
blood.
Erythrocyte • Red blood cell
Leukocyte • White blood cell
Platelet • Cytoplasmic fragment formed
in the bone marrow that helps blood clot.
Antigen • Chemical that stimulates B
lymphocytes to produce antibodies.
Antibody • Protein that B cells of the
immune system produce in response to the presence of a nonself antigen; it reacts with the antigen.
Respiratory System
Inspiration • Breathing in.
Expiration • Expulsion of air from the lungs.
Bronchi • Branches of the trachea that
lead to the lungs.
Alveoli • Air sac of a lung.
Digestive System
Alimentary Canal • Tubular portion of the digestive
tract that leads from the mouth to the anus.
Peristalisis • Rhythmic waves of muscular
contraction in the walls of certain tubular organs (digestion).
Bile • Fluid secreted by the liver and
stored in the gallbladder (emulsifies fats).
Villi • Tiny, finger-like projection that
extends outward from the inner lining of the small intestines.
Nephron • Functional unit of the kidney.
Reproductive System
Puberty • Stage of development in which
the reproductive organs become functional.
Ovulation • Release of an egg cell from a
mature ovarian follicle.
Progesterone • Female hormone secreted by
the corpus luteum of the ovary and the placenta.
Estrogen • Hormones that stimulate the
development of female secondary sex characteristics and produces an environment suitable for fertilization, implantation, and growth of an embryo.
Testosterone • Male sex hormone secreted by
the interstitial cells of the testes.
Zygote • Cell produced by the fusion of
an egg and sperm; a fertilized egg.
Placenta • Structure that attaches the
fetus to the uterine wall, providing for delivery of nutrients to and removal of wastes from the fetus.
Amniotic Fluid • Fluid within the amniotic cavity
that surrounds the developing fetus.
Diseases to Know
Jaundice • A yellowish skin tone, which
can indicate live malfunction.
Diabetes • High blood glucose level and
glucose in the urine due to a deficiency of insulin.
Goiter • Enlarged thyroid gland due to
an iodine deficiency.
Fetal Alcohol Syndrome
• A group of conditions that can occur in a person whose mother drank alcohol during pregnancy.
Diagrams to Know
Divisions of the Body