1st Semester Vocabulary
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1.
acid: compound that forms hydrogen ions (H+) in solution;
24.
below 7 on the pH scale
2.
activation energy: the energy required to begin a chemical
what enters and leaves the cell
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reaction
3.
active site: the area on the enzyme where the substrate attaches
26.
active transport: transport of a substance across a cell
adhesion: the property of sticking together (as of glue and wood)
or the joining of surfaces of different composition; water
possesses this property and causes it to stick to many surfaces
6.
allele: different versions of a gene
7.
amino acid: basic building blocks of protein molecules
8.
anticodon: group of three bases on a tRNA molecule that are
27.
asexual reproduction: reproduction without egg or sperm;
28.
atom: the smallest component of an element having the
29.
ATP: (adenosine triphosphate) main energy source that cells use
for most of their work
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autosome: the chromosomes that are not directly involved in
determining the sex (gender) of an individual
13.
bacteriophage: A virus that infects bacteria
14.
base: compound that produces hydroxide ions (OH+) in
30.
base-pairing rules: the rules stating that cytosine pairs with
guanine and adenine pairs with thymine in DNA, and that
adenine pairs with uracil in RNA
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17.
biology: the study of life
18.
cancer: a growth disorder of cells that occurs when cells divide
uncontrollably within the body; caused by exposure to radiation,
chemicals, or mistakes in the copying of the DNA
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cancer: the uncontrolled growth and division of cells
20.
carbohydrate: organic compound made up of carbon,
32.
chromosome: DNA that begins to coil up and wrap around
33.
clone: an individual that is genetically identical to its parent
34.
codominance: when two dominant alleles are expressed at the
proteins (histones) creating nucleosomes.
same time and both forms of the trait are displayed; red flower
crossed with a white flower produces a flower with red and white
petals
35.
codon: three-nucleotide sequence on messenger RNA that codes
36.
cohesion: the intermolecular force that holds together the
for a single amino acid
molecules in a solid or liquid; water possesses this property and
creates surface tension
37.
carrier protein: a protein that transports substances across a
38.
cell: highly organized, tiny structures with thin coverings called
membranes; the smallest unit of life
23.
cell cycle: a repeating sequence of celluarl growth and division
during the life of an organism; consists of interphase, mitosis,
and cytokinesis.
compound: a substance formed by chemical union of two or
more elements or ingredients in definite proportion by weight
39.
concentration gradient: a difference in the concentration of a
substance across a distance; the path molecules travel (high-tolow or low-to-high) when an imbalance between separated
molecule concentrations exists
40.
control group: a group in an experment that receives on
experimental treatment
cell membrane
22.
complementary: characteristic of nucleic acids in which the
sequence of bases on one strand determines the sequence of
bases on the other
hydrogen, and oxygen atoms; major source of energy for the
human body
21.
chromatid: two exact copies of DNA that make up each
chromosome; sister chromotids are copies of the same
chromosome
binary fission: a form of asexual reproduction that produces
identical offspring (clone); prokaryotes (bacteria) use this to
reproduce
Chloroplast: organelle found in cells of plants, some bacteria,
and some protists that captures the energy from sunlight and
converts it into chemical energy (photosynthesis)
solution; above 7 on the pH scale
15.
Centrosome: structure present in the cytoplasm of animal cells,
important during cell division; functions as a microtubuleorganizing center. A centrosome has two centrioles.
chemical properties of the element
11.
centromere: the point where the two sister chromatids area
attached
typically involves one parent; typically produces clones
(genetically identical offspring)
10.
Centriole: structure in an animal cell that helps to organize cell
division
complementary to an mRNA codon
9.
Central Vacuole: in some protists and in most plant cells, a
large, fluid-filled organelle that stores water, enzymes, metabolic
wastes, and other materials; provides "turgor pressure" to
strengthen the cell wall and provide additional rigidity to the
plant
membrane against the concentration gradient and requiring
energy
5.
Cell Wall: strong wall outside a plant cell's plasma membrane
that protects the cell and maintains its shape
and is acted upon by the enzyme
4.
Cell Membrane: thin, flexible barrier around a cell; regulates
41.
crossing-over: occurs when portions of a chromatid on one
homologous chromosome are broken and exchanged with the
corresponding portions on one of the chromatids of the other
homologous chromosome.
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cystic fibrosis: a fatal disorder in which abnormally thick
mucus builds up in many organs, including the lungs causing
difficulty breathing; caused by a defective gene
43.
45.
deoxyribose: five-carbon sugar that is a component of DNA
nucleotides
46.
dependent variable: the variable that is measured in an
experiment; it is dependent on the changes that occur in the
independent variable
47.
dipoid: when a cell (such as a somatic cell) contains two sets of
chromosomes; when a cell contains two homologues of each
chromosome; when a cell contains homologous pairs; symbol is
"2n"
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50.
exon: sequence of a gene's DNA that transcribes into protein
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experiment: a planned procedure to test a hypothesis
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F1 generation: the first filial generation; the offspring of the P
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F2 generation: the second filial generation; the offspring of the
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facilitated diffusion: the transport of substances through a
structures
generation
F1 generation
cell membrane along a concentration gradient with the aid of
carrier proteins
68.
fertilization: two haploid gametes join to produce a diploid
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gamete: reproductive cells; sex cells, egg and sperm
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gametophyte: the haploid phase in the life cycle of plants that
71.
gene: a segment of DNA that codes for a protein or RNA
72.
gene: sets of inherited instructions for making proteins; code for
73.
gene expression: conversion of the information encoded in a
zygote
produces gametes by mitosis
molecule; a segment of DNA that codes for a specific trait
specific traits; contained in DNA
DNA helicase: enzyme that breaks the hydrogen bonds between
bases and unwinds the nucleotides during DNA replication
51.
63.
DNA: a long linear polymer found in the nucleus of a cell and
formed from nucleotides and shaped like a double helix; the
material that contains the information that determines inherited
characteristics
gene first into messenger RNA and then to a protein, which in
turn, influences the phenotype
DNA plymerase: is an enzyme, adds new nucleotides to a
strand, proofreads DNA strands to see that they are correct,
derives energy from ATP for synthesis of DNA strands
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DNA replication: process by which DNA is copied in a cell
53.
dominant: the expressed form of a trait if it is present
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double helix: shape of a DNA molecule formed when two
74.
75.
twisted DNA strands are coiled into a springlike structure
consisting of nucleotides and held together by hydrogen bonds
between the bases
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ecology: the science that studies the interactions of living
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element: any of the more than 100 known substances (of which
endocytosis: the active transport process that uses energy to
cause the cell membrane to surround a particle and enclose the
particle in a vesicle to bring the particle into the cell
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energy: the capacity for doing work or producing heat
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enzyme: any of several complex proteins that are produced by
cells and act as catalysts in specific biochemical reactions;
specialized proteins that speed up chemical reactions
60.
equilibrium: When the concentration of a solute is the same
throughout a solution
genotype: the set of alleles thta an individual has; indicated by
using letters including capital letters to indicate a dominant
allele and lower case letters to indicate recessive allele
Golgi Apparatus: Organelle that modifies, sorts, and packages
proteins from the endoplasmic reticulum and send proteins to
their final destination
78.
haploid: when a cell (such as a gamete) contains one set of
chromosomes; when a cell contains one homologue of each
chromosome; when a cell does not contain homologous pairs;
symbol is "n"
92 occur naturally) that cannot be separated into simpler
substances and that singly or in combination constitute all
matter
57.
genetics: a branch of biology that focuses on heredity and was
studied by Mendel
organisms with one another and with the nonliving part of their
environment
56.
genetic code: a sequence of nucleotides, read in groups of three
consecutive nucleotides (triplets) that correspond to specific
amino acids, specifies the amino acid sequence of a protein
before a cell divides by mitosis, meiosis, or binary fission
55.
exocytosis: the active transport process that uses energy to
cause a substance to be released from the cell through a vesicle
that transports the substance to the cell surface and then fuses
with the membrane to let the substance out
diffusion: The process by which molecules move from an area
of higher concentration to an area of lower concentration
48.
62.
Cytoskeleton: network of protein filaments within some cells
that helps the cell maintain its shape and is involved in many
forms of cell movement
evolution: small changes in inherited traits of a species over
long periods of time
cytokinesis: the process during cell division in which the
cytoplasm divides; in animal cells, the cleavage furrow is where
the cell separates; in plant cells, the cell plat is where the cell
separates.
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61.
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heredity: the passing of traits from parent to offspring
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heredity: the passing of traits from parents to offsrping
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heterozygous: two alleles of an individual are different
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HIV: a virus that destroys the immune system, causing acquired
immune deficiency syndrome, or AIDS; caused by the exchange
of bodily fluids; a sexually transmitted disease
83.
homeostasis: the maintenance of stable internal conditions in
spite of changes in the external environment
84.
homologous chromosome: chromosomes that are similar in
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size, shape, and genetic content.
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homozygous dominant: two alleles of a particular gene
present in an individaul are dominant
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homozygous recessive: two alleles of a particular gene present
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hypertonic solution: in cells, solution in which the
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88.
hypothesis: an explanation that might be true - a statement
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hypotonic solution: in cells, solution in which the
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incomplete dominance: a trait that has two different alleles,
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independent variable: the factor in an experiment that is
interphase: the first phase of the cell cycle where the cell
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intron: sequence of a eukaryotic gene's DNA that is not
111.
ion: an atom or group of atoms that has a positive (cation) or
112.
ion channel: A transmembrane protein channel that allows a
specific ion to flow across the membrane down its concentration
gradient.
97.
113.
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karyotope: a photo of the chromosomes in a dividing cell that
shows the chromosomes arranged by size; used to diagnose
conditions including trisomy, monosomy and can be used to
determine the sex (gender) of the individual.
99.
lac operon: The operon that controls the metabolism of lactose
100.
114.
101.
law of segregation: when homologous chromosomes and
then chromatids are separated and the two alleles for a trait
separate to go into different gametes
102.
115.
natural selection: the process by which species survive
because they have adapted and are able to reproduce
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nucleic acid: any of various macromolecules composed of
nucleotid chains that are vital constituents of all living cells;
DNA and RNA
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Nucleolus: The organelle where ribosomes are made,
synthesized and partially assembled, located in the nucleus
118.
nucleotide: the building block of a nucleic acid, consisting of a
five-carbon sugar covalently bonded to a nitrogenous base and a
phosphate group.
119.
nucleotide: The building block of a nucleic acid, consisting of
a five-carbon sugar covalently bonded to a nitrogenous base and
a phosphate group.
120.
Nucleus: The organelle that contains the DNA and controls the
processes of the cell; the control center of the cell
121.
observation: the act of noting or perceiving objects or events
using the senses
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oogenesis: the process by which gametes are produced in
female animals; produces the egg and 3 polar bodies
life cycle: the entire life spaln of an organism from one
generation to the next
mutation: a change in the DNA of a gene; can be harmful,
helpful, or have no effect
law of independent assortment: the alleles of different
genes separate independently of one another during gamete
formation guaranteeing variety in the distribution of the paternal
and maternal alleles in the gametes
multiple alleles: genes with three or more alleles; ABO blood
groups
isotonic solution: in cells, solution in which the concentration
of water in the solution is the same as the concentration of water
inside a cell causing an equal movement of water into and out of
the cell
monosaccharide: a simple sugar that is the basic subunit of a
carbohydrate; fructose and glucose
negative (anion) charge
96.
monohybrid cross: a cross that involves one pair of
contrasting traits
translated into a protein
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molecule: the simplest structural unit of an element or
compound
spends 90% of its time; consists of G1, S, and G2 phases
94.
mitosis: the process during the cell cycle in which the nucleus
divides into two nuclei; consists of prophase, metaphase,
anaphase, and telophase
varied; the condition in an experiment that is changed
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Mitochondria: Powerhouse of the cell, organelle that is the
site of ATP (energy) production
homologous chromosomes during meiosis
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metabolism: the sum of all of the chemical reactions carried
out in an organism
concentration of water outside the cell is higher than the
concentration inside the cell; causes a cell to swell as water
enters the cell
independent assortment: the random distribution of
messenger RNA: RNA molecule that carries copies of
instructions for the assembly of amino acids into proteins from
DNA to the rest of the cell
but they are both expressed as an intermediate between the two;
red flower crossed with a white flower produces a pink flower
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meiosis: a form of cell division that halves the number of
chromosomes when forming specilized reproductive cells, such
as gametes or spores; reduction division
that can be tested by additional observations or experimentation
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Lysosomes: Small organelles filled with enzymes; one function
is to break down lipids, carbohydrates, and proteins from food
particles; may also break down old cell parts
in an individaul are recessive
concentration of water outside the cell is lower than the
concentration outside the cell; causes a cell to shrink as water
leaves the cell
lipid: organic molecule made mainly from carbon, oxygen, and
hydrogen atoms; includes fats, oils, steroids, phospholipids, and
waxes
123.
operator: region of chromosome in an operon to which the
repressor binds when the operon is turned off
124.
operon: group of genes operating together
125.
osmosis: diffusion of water molecules through a
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semipermeable membrane from a place of higher concentration
to a place of lower concentration until the concentration on both
sides is equal
126.
ovum: the larger cell that is produced during oogenesis;
typically called the egg; its size allows it to have a rich storehouse
of nutrients to nourish the young organism that develops if
fertilization occurs
127.
147.
148.
P generation: the first two individuals that are corssed in a
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132.
150.
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point mutation: mutation that affects a single nucleotide,
be scattered along the same chromosome or located on different
chromosomes; eye color, height, weight, hair color, skin color
are all examples of this type of trait
134.
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153.
136.
protein: organic molecule that contains carbon, hydrogen,
oxygen, and nitrogen; needed by the body for growth and repair
and to make up enzymes
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154.
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Punnett square: a diagram that predicts the expected outcome
receptor protein: a protein that binds specific signal
recessive: the trait that is not expressed when a dominant form
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replication fork: a Y-shaped point that results when the two
strands of a DNA double helix separate so that the DNA molecule
can be replicated
141.
159.
160.
144.
ribosomal RNA: The most abundant type of RNA, which
together with proteins, forms the structure of ribosomes.
145.
Ribosome: An organelle that functions in the synthesis of
proteins
spore: a haploid reproductive cell produced by meiosis that is
capable of developing into an adult without fusing with another
cell
ribonucleic acid (RNA): single-stranded nucleic acid made
of nucleotides that contain the sugar ribose, a phospate group,
and a nitrogen base
spindle: cell structures made up of both centrioles and
individual microtuble fibers that are invovled in moving
chromosomes during cell division.
their own kind from one generation to the next
143.
spermatogenesis: the process by which sperm are produced in
male animals
repressor: protein that binds to the operator in an operon to
reproduction: the process by which organisms make more of
sperm: male gamete involved in fertlization and creating a
zygote; haploid
158.
switch off transcription
142.
species: a group of geneticall similar organisms that can
produce fertile offspring
157.
of the trait is present
140.
solution: mixture of two or more substances in which the
molecules of the substances are evenly distributed; a mixture in
which one substance is dissolved in another
molecules, which causes the cell to respond.
139.
sodium-potassium pump: A carrier protein that uses ATP to
actively transport three sodium ions out of a cell and two
potassium ions into the cell
of a genetic cross by considering all possible combinations
138.
Smooth Endoplasmic Reticulum: no ribosomes are found
on surface; contains collection of enzymes that perform special
tasks that include the synthesis of membrane lipids and
detoxification; the liver contains a lot of smooth er
prediction: the expected outcome of a test, assuming the
probability: the liklihood that a specific event will occur
sexual reproduction: reproduction using egg and sperm;
typically involves two parents; produces offspring that are
genetically different from the two parents; increases diversity
hypothesis is correct
135.
sex-linked trait: a trait whose allele is located on the X
chromosome; most are recessive; because males only have one X
chromosome and females have two X chromosomes, more males
these traits than females
phenotype: the physical appearance of a trait
polygenic trait: when several genes influence a trait and may
sex chromosome: the chromosomes that contain genes that
will determine the sex (gender) of an individual.
usually by substituting one nucleotide for another
133.
second messenger: a molecule that is generated when a
specific substance attaches to a receptor protein on the outside of
a cell membrane, which produces a change in cellular function
pH: a relative measure of the hydrogen ion concentration
within a solution; a number between 0-14
131.
149.
pedigree: a family history that shows how a trait is inherited
over several generations
Rough Endoplasmic Reticulum: System of internal
membranes within the cytoplasm. Membranes are rough due to
the presence of ribosomes. functions in transport of substances
such as proteins within the cytoplasm
passive transport: the movement of substances across a cell
membrane without the use of energy by the cell; includes
diffusion, osmosis, and facilitated diffusion
RNA polymerase: an enzyme that pries the 2 strands of DNA
apart and hooks together the RNA nucleotides as they base pair
along the DNA template
breeding experiment
128.
RNA: a natural polymer that is present in all living cells and
that plays a role in protein synthesis; takes instructions on
building proteins from the DNA in the nucleus to the ribosomes;
there are three types (messenger, transfer, and ribosomal)
161.
sporophyte: the diploid phase in the life cycle of plants that
produces spores by meiosis
162.
163.
substrate: the substance that will be acted upon by an enzyme
test cross: a cross in which an individual whose phenotype is
dominant, but whose genetope is not known, is crossed with a
homozygous recessive individual
164.
theory: a set of related hypothesis that have been tested and confirmed many times by many scientists; it unites and explains a broad
range of observations
165.
transcription: process in which part of the nucleotide sequence of DNA is copied into a complementary sequence in mRNA
166.
transfer RNA: RNA in the cytoplasm that carries an amino acid to the ribosome and adds it to the growing protein chain
167.
transformation: modification of a cell or bacterium by the uptake and incorporation of exogenous DNA; a change in the phenotype
caused when bacterial cells take up foreign genetic material
168.
translation: the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in
the cytoplasm
169.
true-breeding: all offspring display only one form of a particular trait
170.
uracil: a nitrogen base found in RNA (but not in DNA) and derived from pyrimidine; pairs with adenine
171.
vaccine: substance prepared from killed or weakened pathogens and introduced into a body to produce immunity
172.
Vesicle: small membrane-bound sac that functions in moving products into, out of, and within a cell
173.
virulent: extremely poisonous or injurious; able to cause disease
174.
zygote: the fusion of two haploid games (fertilization) that forms a diploid fertilized egg; the first cell of a new individual