TEAS Science Vocab

Acid

a substance with a pH less than 7

Activation energy

the minimum energy needed to initiate a chemical reaction

Active immunity

protection against a specific pathogen resulting from the production of antibodies in response to the presence of specific antigens

Active transport

movement across a cell membrane that travels against the concentration gradient and thus requires energy

Adaptive defense

a specific response by the immune system to a given pathogen

Adaptive immune system

a kind of passive or active immunity in which antibodies to a particular antigen are present in the body

Adhesiveness

a measure of how well dissimilar particles or surfaces cling to one another

Adrenal

a gland above the kidney that produces hormones to regulate heart rate, blood pressure, and other functions

Aldosterone

a hormone secreted by the adrenal gland that increases reabsorption of sodium ions

Allele

a specific copy of a gene

Allergies

an immune response to a foreign agent that is not a pathogen

Alveoli

tiny air sacs in the lungs where exchange of oxygen and carbon dioxide takes place

Amino acids

the monomers that make up proteins

Anaphase

the stage in mitosis in which the chromosomes are pulled apart to the poles and cell division begins

Anaphase I

the stage in meiosis I in which homologous chromosomes move to opposite ends of the cell

Anaphase II

the stage in meiosis II in which sister chromatids separate and move to opposite ends of the cell

Anatomical position

standard positioning of the body as standing; feet together; arms to the side; with head, eyes, and palms of hands forward

Angiotensin II

a secretion that acts to restore blood volume and blood pressure by constricting blood vessels, stimulating thirst, and stimulating production of aldosterone and antidiuretic hormone

Anion

a negatively charged ion

Antagonist

the relaxed muscle in the pair of muscles that is involved in a given movement

Antibody mediated immunity

A defense that employs B-cells to create antibodies that tag pathogens for later destruction, also known as humoral immunity

Antidiuretic hormone

a secretion from the pituitary gland that increases the amount of water able to be reabsorbed from a collecting duct

Antigen presenting cell

a cell that displays foreign antigens with major histocompatibility complexes on their surfaces

Antigens

substances on the surfaces of agents that act to identify them, to the body, as being native or foreign

Antimicrobial

a substance that kills or inhibits growth of microorganisms with minimal damage to the host

Anus

the opening of the rectum from which solid waste is expelled

Apocrine sweat gland

accessory structures of the dermis that are in physical association with hair follicles, producing a secretion with an odor (possibly a sex pheromone to humans)

Appendicular skeleton

the portion of the skeleton made up of our appendages, such as the bones of our arms, legs, hands, and feet

Arteries

vessels that carry blood away from the heart and towards other body parts

Asthma

a lung disease characterized by inflamed, narrowed airways and difficulty breathing

Atom

the fundamental constituent of matter that retains the properties of an element, the smallest unit that has a unique identity

Atomic mass

the sum of the masses of protons and neutrons in one atom of an element

Atomic number

the number of protons in the nucleus of an atom

Autoimmune disease

a pathology that results from the immune system mistaking part of the body as a pathogen

Autonomic nervous system

the part of the peripheral nervous system that regulates unconscious body functions such as breathing and heart rate

Axial skeleton

the portion of the skeleton consisting of the skull, ribs, sternum, and spinal column

Axon

a nerve fiber that carries a nerve impulse away from the neuron cell body

Bacteria

unicellular organisms that are capable of causing disease

B cells

lymphocytes that mature in bone marrow and make antibodies in response to antigens

Ball and socket joints

point of articulation that allows for abduction, adduction, circumduction, and rotation, the hip socket is one example of this

Base

a substance with a pH greater than 7

Bolus

a mass of food that has been chewed and swallowed

Bone marrow

a soft material within spongy bone and medullary cavity of long bones

Bone

hard calcified material that makes up the skeleton

Bowman’s capsule

a cup-like structure that surrounds and collects filtrate from the glomerulus

Brittle bone disease

a group of diseases that affect collagen and result in fragile bones

Bronchi

the main passageways directly attached to the lungs

Bronchioles

small passages in the lungs that connect bronchi to alveoli

Buffer

a solution of weak acid and its conjugate base or weak base and its conjugate acid that maintains the proper pH of the body

Canaliculi

microscopic canals in ossified bone

Capillaries

small vessels that connect smaller arteries, called arterioles, to smaller veins, called venules, and carry out gas exchange

Carbohydrates

sugars and starches which the body breaks down into glucose

Cardiac muscle

involuntary muscle found in the heart

Cardiovascular system

the system comprised of the heart and blood vessels

Cartilage

tough, flexible connective tissue found in parts of the body such as the ear

Catalyst

a substance that increases the rate of a chemical reaction without undergoing permanent chemical change by lowering the activation energy required for the reaction to occur

Cation

a positively charged ion

Cell mediated immunity

a type of adaptive immunity in which T lymphocytes attack parasitic worms, cancer cells, transplanted tissues, or cells that contain pathogens

Cell (plasma) membrane

a cell organelle that maintains its environment through the property of selective permeability

Cells

the basic structural unit of an organism from which all living things are created

Cellular functions

processes that include growth, metabolism, replication, protein synthesis, and movement

Central nervous system

the part of the nervous system that consists of the brain and the spinal cord and acts as the command center for all communication and actions of the body

Ceruminous glands

accessory structures that produce ear wax, found only in the dermis of the ear canal

Cervix

the passage that forms the lower part of the uterus

Chemical equation

mathematical representation of a chemical reaction

Chromatid

one of two duplicates of a chromosome formed during the cell cycle

Chromosome

a structure made of protein and one molecule of DNA that contains genetic information

Chyme

the semifluid mass of partly digested food that moves from the stomach to the small intestine

Codons

triplets of nucleotides that code for amino acids

Cohesion

the tendency of similar molecules to stick to each other or group together

Collagen

the primary structural protein of connective tissue

Commensal microorganisms

microscopic organisms that live in or on the human body without causing it harm

Compact (dense) bone

bone containing densely packed osteons that make up the peripheral layer of bone

Complementary strand

a molecule of RNA (or a strand of DNA) synthesized from a complementary template strand

Compound

a substance made of two or more elements

Concentration of a solution

the quantity of solute in a given quantity of solution

Contraction

the process leading to shortening and/or development of tension in a muscle

Controlled variable

the condition that is kept the same in an experiment

Covalent bond

a chemical bond in which electron pairs are shared between atoms

Cutaneous vasoconstriction

a decrease in the diameter of blood vessels in the dermis that reduces blood flow through the skin

Cutaneous vasodilation

an increase in diameter of blood vessels in the dermis that reduces blood flow through the skin

Cystic fibrosis

a genetic disorder that affects the lungs and other organs, characterized by difficulty breathing, coughing up sputum, and lung infections

Cytokines

cell signaling molecules released primarily by helper T-cells and macrophages, with some activating cytotoxic T-cells

Cytoplasm

the material within a eukaryotic cell that supports and suspends structures inside the cell membrane and transfers materials required for cellular processes

Cytotoxic T cells

the category of lymphocyte that attacks foreign cells

Dehydration reaction

a chemical reaction between two molecules in which a water molecule is released and a covalent bond forms; often requires an input of energy; polymers are built as a result of this reaction

Dendrite

a nerve fiber that carries a nerve impulse towards the neuron cell body

Dendritic cells

antigen presenting cells that process antigen and present it to T cells

Density

the ratio of mass to volume

Deoxyribonucelic acid (DNA)

the material that contains genetic information and is responsible for directing protein synthesis in living organisms

Deoxyribose sugar

the sugar portion of deoxyribose nucleotide

Dermis

the middle layer of skin

Diabetes

pathologically high blood sugar levels that result from a pancreatic hormone regulation malfunction

Diastole

the portion of the cardiac cycle in which the heart refills with blood

Diffusion

the passive movement of a substance from an area of high concentration to an area of low concentration

Dihybrid cross

a cross between parents heterozygous at two specific genes

Dilution

the addition of solvent to decrease the concentration of solute in a solution

Directional terminology

words used to explain relationships of locations of anatomical elements (distal, posterior, medial)

Disease

a condition that deteriorates the normal functioning of cells, tissues, and/or organs

Diuretic

any substance that causes water to be lost from the body through urination