Science Key Terms 1 Flashcards
Acid
A substance with a pH less than 7
Activation Energy
The minimum energy required 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. From areas of low to high concentrations.
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 the 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 take place.
Amino Acids
The monomers that make proteins
Anaphase
The stage of mitosis in which the chromosomes move to opposite ends of the cell.
Anaphase I
The stage of meiosis I in which homologous chromosomes move to opposite ends of the cell.
Anaphase II
The stage of 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.
antibody
A blood protein that counteracts a specific antigen
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 histocampitability complexes on their surfaces.
antigens
Substances on their surfaces of agents that act to identify them, to the body, as being native or foreign.
antimicrobial
A substance that kills or inhibits growth or microorganisms with minimal damage to the host.
anus
The opening of the rectum, which solid waste is expelled.
apocrine sweat gland
Accessory structures of the dermis that are in physical association with hair follicles, producing secretion with an odor (possibly a sex pheromone to humans).
Appendicular Skeleton
The portion of the skeleton made up of our appendages-the bones of our arms, legs, hands, and feet.
Arteries
V
Vessels that carry blood away from the heart toward 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. It is 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 thtat allows for abduction, adduction, circumduction, and rotation. The hip or shoulder socket is one example of a ball and socket joint.
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 spongey 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 a weak acid and its conjugate base or a weak base and its conjugate acid. Buffers maintain 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 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 containing pathogens. Does not involve antibodies,but cytotoxic t cells and cytokines.
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 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. Only found 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 the 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. There are a total of 64 codons.Nucleotides make up codons: Adenine, Thymine, Cytosine, Guanine and Uracil (Thymine is replaced by Uracil inRNA).
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 the bone.
complementary strand
A molecule of RNA (or a strand of DNA) synthesized from a complementary template strand.
compound
A substance made up 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 the diameter of blood vessels in the dermis that increases 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. Certain cytokines activate 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 covalent bond forms, often requires 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 material and present it to T cells. immune cells that present antigens to other immune cells, triggering the body’s immune response. They are found in many tissues, including the skin.
density
The ratio of mass to volume
Deoxyribosenucleic acid (DNA)
The material that contains genetic information and is responsible for directing protein synthesis in living organisms.
Deoxyribose sugar
The sugar portion of a deoxyribose nucleotide
dermis
the middle layer of the 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 movemement of a substance from an area of high concentration to an area of low concentration.
dihybrid cross
A cross between heterozygous parents at two specific genes for two different traits.
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, etc).
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.
dominant
Refers to the most powerful trait or the allele for that trait.
eccrine sweat glands
Accessory structures originating throughout the dermis of the human body that secrete sweat, used primarily for regulation of body temperature.
electron
A negatively charged atomic particle.
electron microscope
A magnification instrument that forms an image using a beam of electrons that travel at high speeds and form a wavelike pattern.
Element
Pure substances that cannot be broken into simpler substances.
empirical evidence
Evidence generated through experimentation
