Science Key Terms 3 Flashcards
mole
A unit of a substance that is equal to exactly 6.02214076 x 10^23 particles of that substance.
molecule
An arrangement of two or more atoms bonded together.
monohybrid cross
A cross between parents heterozygous at one specific gene.
monomers
Molecules that can bond to similar or identical molecules to form a polymer.
mouth
The oral cavity at the entry to the alimentary canal.
muscle
Fibrous tissue that produces force and motion to move the body or produce movement in parts of the body.
muscular system
An integrated system in the body that is vital for controlling involuntary and voluntary movement .
mutation
A permanent change in the nucleotide sequence of DNA that may arise during replication.
negative feedback
A mechanism that includes the monitoring for specific homeostatic levels and a signal to a gland. This signal stimulates or inhibits the gland’s secretion in order to maintain homeostasis or cause compensations that returns the level to homeostasis.
nephron
A system of microscopic tubes in the kidneys that use various pressure levels to remove wastes and reabsorb important molecules and water. Expells urine
nerve
A long bundle of neuronal axons that transmits signals to and from the central nervous system.
nervous system
A complex system that controls and affects every part of the body in daily life functions and in the constant drive to maintain homeostasis Neuron Cell of the nervous system that conducts the electrical nerve impulse.
neutralization reaction
A chemical reaction in which mixing an acid with a base causes H+ from the acid to combine with the OH- from the base, forming water.
neutron
An atomic particle with no electric charge.
non-Mendelian Inheritance
Inheritance of traits that do not follow Mendelian patterns of inheritance.
noncovalent bond
A relatively weak bond, like a hydrogen bond or an ionic bond; in macromolecules, many noncovalent bonds work together to give the macromolecule its functional three-dimensional shape.
noninfectious diseases
Diseases that cannot be transmitted directly from one person to another.
nonmetal
Any element or substance that is not a metal
nucleic acids
Long molecules made of nucleotides; DNA and RNA
nucleotides
The monomers used to build DNA and RNA.
nucleus
A large organelle within a cell that houses the chromosomes and regulates the activities of the cell.
nucleus (atom)
The central part of an atom that contains the protons and neutrons.
orbital
An area around the nucleus where an electron can be found.
organ
A structure formed from various tissues that performs a specific function in an organism.
organ systems
Functional groups of organs that work together within the body: circulatory, integumentary, skeletal, reproductive, digestive, urinary, respiratory, endocrine, lymphatic, muscular, nervous.
organelle
A specialized part of a cell that has a specific function and is found in the cell’s cytoplasm.
organic molecule
A molecule found in a living thing that contains carbon.
osmosis
A specific type of diffusion in which water moves across a semipermeable membrane from an area of high concentration to an area of low concentration.
osteoarthritis
Degenerative joint disease
osteoblasts
a cell that secretes the matrix for bone formation. Form new bones and grow and heal existing ones.
osteoclasts
cells that remove bone
Osteocytes
Osteocytes are star shaped cells that maintain bone and are able to sense physical stress. a cell that lies within the substance of fully formed bone.
osteogenesis imperfecta
Brittle bone disease. a genetic disorder that causes bones to become weak and fragile, making them prone to fractures
osteons
Tubular structures that make up compact bone
osteoporosis
A disease that causes brittle, fragile bones.
ova (eggs)
Female gametes
ovaries
The female gonads. Organs in which eggs are produced for reproduction.
oxytocin
A hormone made by the hypothalamus and stored in the posterior pituitary. One of its functions is to stimulate uterine contractions during child birth.
pancreas
The gland of the digestive and endocrine systems that produces insulin and secretes pancreatic juices.
parasites
Microbes that are not free-living and must find a host from which to gain nutrients.
parathyroid
An endocrine gland in the neck that produces parathyroid hormone.
passive immunity
Temporary immunity gained by a body that has acquired antibodies from an outside source, premade antibodies. Ex: Placenta and breast milk offer protection against infections.
passive transport
Movement across a cell membrane that does not require energy input.
pathogen
An infectious agent
pepsin
A stomach enzyme that breaks down proteins.
peptide bond
The link between amino acids in a protein.
penis
Organ for elimination of urine and sperm from the male body.
perfusion
The passage of the fluid to an organ or a tissue.Perfusion is the process of bodily fluids, like blood, passing through the circulatory or lymphatic system to a tissue or organ
period
One of seven horizontal rows in the periodic table.
periodic table
The table of elements expressed as columns and rows.
periosteum
A thin layer that surrounds the bone and is the surface for attachment of tendons and ligaments.
peripheral nervous system
The part of the nervous system that consists of all the nerves and ganglia that branch out from the brain and spinal cord to the rest of the body, allowing signals sent by the brain to reach their target destinations.
peristalsis
A series of muscle contractions that move food through the digestive tract.
pH
A logarithmic scale based on the amount or concentration of hydrogen ions (H+) in a solution, calculated pH= -log[H+] and used to express acidity or basicity.
phagocytosis
Ingestion of particles by a cell or phagocyte, engulfing and destroying foreign particles, such as bacteria, viruses, and dead cells. Besides macrophages, other cells that perform phagocytosis include neutrophils, monocytes, dendritic cells, eosinophils, and osteoclasts; these cells are collectively called “professional phagocytes”
Phenotype
Physical appearance of a trait formed by genetics and environment.
phosphate group
A phosphorus atom bound to four oxygen atoms. PO34-
phosphodiester bond
A covalent bond that links two nucelotides together in a nucleic acid molecule. Phosphodiester bonds are found in DNA and RNA, and they form the sugar-phosphate backbone of these nucleic acids.
pineal gland
A small gland near the center of the brain that secretes melatonin.
pituitary gland
The endocrine gland at the base of the brain that controls growth and development.
placebo
A substance with no medicinal effect that can be used as a control in an experiment.
pleura
A membrane around the lungs and inside the chest cavity.
polymer
A substance composed of similar units bonded together. a large molecule made up of many smaller units called monomers that are chemically bonded together. The word “polymer” comes from the Greek words poly- meaning “many” and -mer meaning “part” or “unit”.
Polysaccharides
Carbohydrate polymers made of many sugar molecules.
positive feedback
A mechanism that stimulates glandular secretions to continue to increase, temporarily pushing levels further out of homeostasis, until a particular biological effect is reached (e.g. expulsion of the fetus during childbirth).
prime mover
The contracting muscle in the pair of muscles that is involved in a given movement; also called the agonist.
products
In a chemical equation, the substances on the right side of the equation; the substances that are formed in a chemical reaction.
prophase
The stage in mitosis in which chromosomes condense in preparation for being pulled apart.
prophase I
The stage of meiosis I in which chromosomes condense and form homologous pairs.
prophase II
The stage in meiosis II in which chromosomes in the haploid daughter cells condense.
prostate
The gland in males that controls the release of urine and secretes a portion of semen that enhances motility and fertility of sperm.
proteins
Molecules composed of amino acids joined by peptide bonds
proton
A positively charged atomic particle
protozoans/protists
Unicellular aerobic eukaryotes. They are the largest group of organisms in the world in terms of numbers, biomass, and diversity.
proximal tubule
The first location where glucose and other useful solutes are reabsorbed back into the blood through the walls of the surrounding capillaries. It connects the Bowman’s capsule to the Loop of Henle.
puberty
A physiological period in which changes in hormone levels cause a general “growth spurt” and development of secondary sex characteristics.
Punnett square
A square diagram used to determine the various genotype combinations that may be passed from parent to offspring and their likelihood of occuring.
reactants
In a chemical equation, the substances on the left side of the equation, the starting materials in a chemical reaction.
recessive
Refers to traits that are masked if dominant alleles are also present; also refers to the allele for that trait
rectum
The last section of the large intestine, ending with the anus.
reference planes
Planes dividing the body to describe: sagittal,coronal, and transverse.
reflex
An involuntary action to a stimulus.
relaxation
Release of tension in a muscle
releasing hormones
Chemical messengers that stimulate the production of certain hormones
renal arteries
The two branches of the abdominal aorta that supply the kidneys with oxygen
renal cortex
The outer layer of the kidney
renal medulla
The innermost part of the kidney. Located below the renal cortex
renal pelvis
The center of the kidney where urine collects before moving to the ureter.
renal vein
A vein carrying blood from a kidney to the inferior vena cava.
renin
An enzyme released by the kidney when reduced blood pressure is detected by baroreceptors in aorta and carotid arteries.
rheumatoid arthritis
A progressive autoimmune disease that causes joint inflammation and pain
ribonucleic acid (RNA)
An important biological macromolecule that is present in all cells controls the intermediate steps involved in protein synthesis.
ribosome
A protein-RNA complex that is the site of protein synthesis
rough endoplasmic reticulum
A cell organelle containing ribosomes that synthesizes and processes proteins in the cell
saliva
The clear fluid found in the mout, also known as spit.
salt
A chemical compound formed from the reaction of an acid with a base, with at least part of the hydrogen of the acid replaced by the cation.
saturated solution
A solution containing the maximum possible amount of solute.
sarcomere
Contracting unit of a muscle
scientific hypothesis
A prediction of what will occur in an experiment based on previous research.
scrotum
The pouch of skin that contains the testicles
sebaceous glands
Accessory structures originating in the dermis that secrete sebum onto hair emerging from the hair follicle.
short bones
Bones that are similar in both length and width, such as those found in the wrist or ankles. They have limited articulation with each other as gliding joints
SI units (Systeme Internationale)
International System of Units based on meters, kilograms, seconds, amperes, Kelvin, candela, and mole. Commonly known as the metric system.
Skeletal Muscles
Muscles that attach to bones and are connected to and communicate with the central nervous system
Skeletal system
The system of bones in the body that provides protection for delicate organs and serves as the scaffold against which muscles pull for movement. It has three main functions: movemement, protection, and storage of minerals and fat.
Skin
The thin layer of tissue that covers the body.
Small intestine
The part of the GI tract between the stomach and large intestine that includes the duodenum, jejunum, and ileum, where digestion and absorption of food occurs.
smooth endoplasmic reticulum
A cell organelle that synthesizes and concentrates lipids in the cell; does not contain ribosomes.
smooth muscle
Muscle that can be found in the walls of hollow organs, such as stomach and intestines.
Solute
The substance that dissolves in a solvent to form a solution
Solution
A homogeneous mixture of two or more substances whose components are uniformly distributed on a microscopic scale.
solvent
The substance in which a solute is dissolved to form a solution.
Somatic nervous system
The part of the peripheral nervous system that controls conscious skeletal muscle function.
sperm
Male gametes
Spongy bone
A type of bone having fewer osteons, and therefore, lighter than compact (dense) bone.
