Glossary Terms Flashcards
(196 cards)
1
Q
Adaptation
A
an inherited characteristic that improves an organism’s ability to survive and reproduce in a particular environment
2
Q
agglutination
A
the clumping together of red blood cells or microorganisms in the presence of a specific antibody
3
Q
alkaptonuria
A
an inherited metabolic disorder that affects the metabolism of certain amino acids and leads to darkening of the urine to the excretion of homogentisic acid
4
Q
allele
A
one of the alternative forms of a gene
5
Q
allopatric speciation
A
the formation of two species that occurs when sub-populations of a species are reproductively isolated due to geographic seperation
6
Q
amino acid
A
the basic building block of proteins
7
Q
amniocentesis
A
a procedure used to recover a sample of amniotic fluid surrounding a fetus in the womb for the purpose of performing genetic tests
8
Q
amoeboid
A
having no definite shape, resembling the form or type of movement of an amoeba
9
Q
anaphase
A
the third stage of mitosis when sister chromatids split and move toward opposite poles of the cell
10
Q
antibody
A
a protein produced by immune cells that binds to a specific antigen to neutralize its effects
11
Q
anticodon
A
the triplet of nucleotides in the transfer of RNA that is complementary to a triplet base (codon) in the messenger RNA
12
Q
antigen
A
a substance that evokes the production of an antibody
13
Q
asexual reproduction
A
a type of reproduction involving only one parent without the fusion of gametes (sperm and egg); usually produces genetically identical offspring
14
Q
ATP (adenosine triphosphate)
A
a temporary energy storage molecule for most cells
15
Q
autophagy
A
a controlled digestion process in which a cell’s own subcellular organelles are broken down and recycled
16
Q
autosome
A
any eukaryotic chromosome other than a sex chromosome
17
Q
bacteriophage
A
a virus that infects bacteria
18
Q
binary fission
A
a type of asexual reproduction in which a parent cell divides into two genetically identical daughter cells
19
Q
binomial theorem
A
the theorem that describes the expansion of any power of a binomial, that is, (a+b)^m
20
Q
biopsy
A
the removal of a piece of tissue from a living body for diagnostic studies
21
Q
biotechnology
A
the use of molecular techniques in living organisms to manufacture useful products
22
Q
blending inheritence
A
a historically influential but factually incorrect notion that organisms contain a blend of traits from their parents
23
Q
budding
A
a type of asexual reproduction in which a new organism grows from the body of the parent, eventually detaches from the parent , and lives independently
24
Q
cancer
A
a disease caused by abnormally rapid proliferation of body cells
25
carbohydrate
a sugar that contains carbon, hydrogen, and oxygen in the ratio 1:2:1 (CH2O)
26
carrier
in genetics, an individual who is heterozygous for a particular trait
27
cell
the basic structural and functional unit of living organisms
28
cell cycle
a series of orderly events a eukaryotic cell goes through, from a dividing parent cell to two daughter cells
29
cell theory
the theory that cells are the basic unit of life and that all cells arise from preexisting cells
30
cellular respiration
the metabolic pathways by which food molecules are broken down and energy is released and harvested by the cell
31
central vacuole
a large organelle in plant cells that stores the waste products of metabolism, maintains turgor pressure, and maintains growth
32
Centrifugation
A laboratory technique in which a sample is spun around a central axis at a high speed to separate its contents based on their size, density, or weight
33
Centriole
A structure in animal cells composed of bundles of microtubule triplets during cell division
34
Centromere
A region where sister chromatids (duplicated chromosomes) are joined and to which spindle fibers are attached during cell division
35
Chorionic villus sampling (CVS)
A procedure in which a sample of the fetal chorionic villa (part of the placenta) is removed for genetic testing
36
Chromatid
One of a pair of identical chromosomes after DNA replication in the cell cycle
37
Chromatin
A dispersed DNA-protein complex that makes up eukaryotic chromosomes
38
Chromatography
A laboratory procedure used to separate and isolate substances in a mixture based on the physical or chemical properties of the constituents
39
Chromosome
A complex structure in the nucleus of eukaryotes or in the nucleoid region of prokaryotes that is comprised of DNA
40
cilia (sing. cilium)
short microscopic projections of the cell surface specialized for locomotion
41
cleavage
the first few cell divisions of an animal zygote
42
coated pit
a specialized depression on the surface of a cell membrane, formed as a result of receptor-mediated endocytosis
43
co-dominance
a type of inheritance in which two separate alleles at a locus are equally expressed and produce different phenotypic traits
44
codon
a triplet of nucleotides in messenger RNA coding for a specific amino acid; the basic unit of the genetic code
45
conjugation
the transfer of genetic material by joining two bacteria or protists
46
cystic fibrosis
an often fatal genetic disease characterized by the production of thick mucus that obstructs various ducts in different organs, leading to infection and interference of important functions
47
cytokinesis
the cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separation into two daughter cells
48
cytological
relating to the science of cytology, a sub-discipline of biology that studies the microscopic structure of cells
49
cytoplasm
the content of a cell inside the plasma membrane and outside the nucleus
50
cytoskeletal elements
a network of protein filaments in the cytoplasm of a cell that serves various functions in support, movement and transport: the system includes microtubules, intermediate filaments, and microfilaments
51
cytosol
the fluid portion of the cytoplasm
52
deoxyribose
a five-carbon sugar that is a building block of DNA and some nucleotides
53
DNA (deoxyribonucleic acid)
the genetic material for all organisms except the RNA virus
54
dominant
describes an allele that determines the phenotype when the genotype is heterozygous
55
double helix
the spiral shape of a double-stranded DNA molecule
56
duplication
the production of a second copy of a particular sequence of DNA
57
electrophoresis
the method of distinguishing molecules, such as a mixture of proteins or DNA, according to their motility in a gel-like substance in an electric field
58
embryonic
related to an embryo, or being in the state of an embryo
59
endocytosis
a process by which liquids or solid particles are taken up by a cell through invagination of the plasma membrane
60
endometrium
the inner epithelial lining of the uterus
61
endoplasmic reticulum
a network of tubules that is part of the endomembrane system in eukaryotic cells specializing in the synthesis and modification if biological molecules
62
endosymbiosis
the theory that ancient large eukaryotic cells ingested small prokaryotes, which became subcellular organelles (such as mitochondria and chloroplasts) of the large host cell
63
epigenetics
the scientific study of changes in the inheritance of traits that occur without changes in the DNA sequence
64
epistasis
an interaction between two genes in which one gene alters the expression or effect of another gene
65
erythropoietin
a hormone produced by the kidney in response to low levels of blood oxygen that stimulates the production of red blood cells by the bone marrow
66
eugenics
the study or practice of altering a population, especially of humans, by controlling fertility and selective breeding for desirable traits
67
evolution
the process of change by which new species develop from preexisting ancestral species over time
68
exocytosis
a process by which a vesicle within a cell fuses with the plasma membrane and releases its contents to the outside
69
exon
the nucleotide sequence of a gene that codes for a protein
70
familial hypercholesterolemia
an inherited metabolic disorder that results in high levels of blood cholesterol; the disorder is caused by a lack or malfunction of receptors for the low-density lipoprotein (LDL) that removes cholesterol from the blood
71
flagella (sing. flagellum)
long, whip-like appendages that propel and move cells
72
functional genomics
the branch of genomics that analyzes the biological function of genes and their products
73
gemmule
a hypothetical particle postulated to be the hereditary unit (now recognized as incorrect) in the theory of pangenesis
74
gene
a unit of hereditary consisting of a specific sequence of nucleotides in DNA (or RNA in some viruses)
75
gene expression
the process by which the information encoded in a gene is converted first into messenger RNA and then to a protein
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genetic code
the code relating nucleotide triplets in messenger RNA (or DNA) to amino acids in proteins
77
genetic drift
a change in the allele frequency in a population that occurs by chance
78
genetics
a sub-discipline of biology that studies genes and heredity
79
genome
the full set of DNA in a cell or organism
80
genomic DNA
the DNA constituting the genome of a cell or an organism, as distinguished from extra chromosomal DNAs, such as plasmids
81
genotype
the genetic makeup (set of alleles) of an organism
82
germ cell
a reproductive cell (gamete), or one of its precursors, of a multicellular organism
83
germ line
the lineage of cells from which gametes are derived
84
glycoprotein
a protein with one or more chains sugar (carbohydrate) attached
85
golgi apparatus
a stack of tubules that is a component of the endomembrane system in eukaryotic cells that modifies, sorts, and packages products delivered from the endoplasmic reticulum
86
Hardy-Weinberg equilibrium
the condition when a population is not evolving
87
Hardy-Weinberg theorem
the principle that allele frequencies and genotypes in a population remain constant over generations
88
heredity
the process by which characteristics are passed from one generation to the next
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heritable
capable of being passed down from one generation to the next
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heterozygous
having two different alleles at a gene locus for a particular trait
91
homologous chromosomes
a pair of chromosomes with the same set of genes, each derived from one parent
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homozygous
having identical alleles at a gene locus for a particular trait
93
human immunodeficiency virus (HIV)
the virus that causes acquired immune deficiency disorder (AIDS) by destroying the T cells (a type of white blood cell) of the immune sytem
94
hybrid
the offspring of a cross between two species
95
hybridize
1. in agriculture, to cross breed two different varieties to generate an offspring with traits from both parents 2. in molecular biology, to combine strands of nucleic acid from different sources to form a new species of double-stranded nucleic acid
96
hydrophobic
having a tendency to repel water and not dissolve or mix with water
97
hypothesis
a tentative explanation or answer to a question that can be tested and falsified by the scientific method
98
incomplete dominance
a pattern of inheritance in which the heterozygous phenotype is intermediate between two homozygous phenotypes
99
insulin
a hormone synthesized by pancreatic islet cells that promotes the uptake of glucose by the cell for energy production, thereby lowering the blood glucose level
100
insulin-resistance
a state of diminished effectiveness of insulin in lowering levels of blood glucose, usually resulting from prolonged insulin treatments and loss of responsiveness of cells associated with diet, lack of exercise, and obesity
101
interferon
a defensive protein produced by virus-infected cells that is capable of increasing the resistance of other cells to the virus
102
intermediate filaments
one of three types of cytoskeletal elements in eukaryotic cells involved in maintaining the cell shape and stabilizing organelles
103
intron
a part of the nucleotide sequences of a gene that does not code for a protein
104
karyotyping
a set of photographs displaying paired chromosomes by size and shape
105
kinetochore
the specialized region on the centromere of the chromatid to which microtubules attach during cell division
106
law of dominance
one of the rules of inheritance formulated by Mendel which states that one of the alleles coding for a particular trait will be expressed (dominant allele) while the other will not be expressed (recessive allele)
107
law of independent assortment
one of the rules of inheritance formulated by Mendel which states that nonhomologous chromosomes are sorted independently from each other during gamete formation
108
law of segregation
one of the rules of inheritance formulated by Mendel which states that alleles or homologous chromosomes are segregated during gamete formation
109
linked genes
genes on the same chromosome that share a close association such that they tend to be inherited together
110
lipid
one of a group of nonpolar and hydrophobic molecules consisting mainly of a hydrocarbon chain
111
low-density lipoprotein (LDL) cholesterol
one type of lipoprotein that transports and delivers cholesterol to the cell; LDLs are "bad" lipoproteins associated with a higher risk of cardiovascular disease
112
lysosome
an organelle specializing in digestion in animal cells and some protists
113
macroevolution
evolution on a grand scale that begins with the formation of new species and includes mass extinction and major geological events over long periods of time
114
meiosis
a special type of cell division that occurs in sexually reproducing species during which one diploid germ cell produces four haploid gametes
115
messenger RNA (mRNA)
a type of RNA that is transcribed from DNA and acts as the message for the translation of proteins
116
metaphase
the second stage of mitosis when chromosomes with sister chromatids line up along the metaphase plate
117
microevolution
evolutionary change on a small scale that is defined as changes in gene frequencies in a population over time
118
microfilaments
one of three types of cytoskeletal elements in eukaryotic cells involved in maintaining the cell shape and cell movement
119
micro RNA (miRNA)
a class of short (~22 nucleotides) RNA involved in post-transcriptional regulation
120
microtubule organizing centers (MTOC)
the region or structure where spindle microtubules are organized during cell division
121
microtubules
one of three types of cytoskeletal elements in eukaryotic cells involved in transporting organelles and as a structural component of cilia and flagella
122
mitochondrial DNA
circular DNA found in the mitochondrion believed to be of prokaryotic origin; because mitochondria are generally carried in egg cells but not in sperm, mitochondrial DNA is passed to offspring from mothers, but not fathers
123
mitosis
a type of cell division in multicellular organisms that produces genetically identical cells
124
modern synthesis
the consolidation of Darwin's theory of evolution by natural selection with evidence from the Mendelian theory of genetics, population genetics, and other fields
125
multipotent
having the potential to form a set of multiple cell types in the body
126
mutation
a change in the nucleotide sequence of DNA in an organism
127
natural selection
a process in which individuals with certain heritable traits are more likely to survive and reproduce in a particular environment
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nonpolar
molecules that have equal sharing of electrons
129
nucleic acid
a polymer consisting of many mononucleotides; e.g., DNA and RNA
130
nuclein
a crude mixture of nucleic acids and many proteins extracted from a cell
131
nucleoid
the region containing all or most of the genetic material of prokaryotic cells
132
nucleolus
a round granular structure within the nucleus of a cell, composed of protein and RNA; involved with ribosomal RNA synthesis and the formation of ribosomes in eukaryotes
133
nucleotide
a building block of DNA and RNA which consists of a phosphate and a five-carbon sugar with a nitrogenous base attached
134
nucleus
a membrane-bound subcellular structure where DNA is located in eukaryotic cells
135
oncogene
a gene that stimulates cell proliferation or causes cancer if mutated or abnormally activated
136
oogonia (sing. oogonium)
undifferentiated female germ cells that give rise to oocytes through meiosis
137
organelle
a specialized structure that performs a particular function function in the cytoplasm of eukaryotic cells
138
organism
a living thing
139
pangenesis
an incorrect theory of heredity that posited that a reproductive cell contains gemmules derived from individual cells from different parts of the organism
140
pedigree
a chart of a family tree depicting the pattern of transmission of a particular trait
141
phagocytosis
a type of endocytosis in which solid particles are ingested by a cell
142
phenotype
the physical or biochemical characteristics of an organism that are the result of interaction between genotype and the environment
143
phospolipid
a lipid molecule containing fatty acids and a phosphate group that is an important constituent of membranes
144
photosynthesis
metabolic processes, carried out by green plants and some bacteria, by which visible light is used to synthesize compounds such as ATP and glucose
145
pinocytosis
a type of endocytosis in which the cell takes in fluid and dissolved substances by invagination of the plasma membrane
146
placenta
the organ that is formed in female mammals during pregnancy that provides for the nourishment of the fetus and the elimination of the fetal waste products
147
plasma membrane
the border of all cells that serves as a selectively permeable barrier and site of communication with the external environment
148
pleiotropy
occurs when a single gene can determine more than one distinct phenotype effect
149
pluripotent
having the potential to form any type of cell in the body
150
pnuemonia
inflammation of the lungs usually caused by infection with viruses or bacteria
151
polygenic
a pattern of inheritance in which a single phenotypic trait is determined by the additive effect of multiple genes
152
polymerase chain reaction (PCR)
a molecular biology technique in which DNA sequences are amplified for the purpose of research, forensics, or medicine
153
polyploidy
having more than two sets of genes and chromosomes
154
population genetics
a sub-discipline of genetics that studies the processes influencing gene frequencies in a population
155
primer
a strand of nucleic acid, usually RNA, which is complementary to a given DNA sequence for DNA replication
156
product (multiplication) rule
a formula use to find the derivatives of products of two or more functions
157
prokaryotic cell
a cell that lacks a distinct nucleus and other subcellular organelles
158
prophase
the first stage of mitosis when chromosomes with sister chromatids condense and the nuclear envelope disappears
159
protein
a macromolecule made up of a sequence of amino acids that performs various functions in a cell
160
Punnet square
a diagram used to predict the results of a genetic cross
161
receptor
a protein located on the surface or inside of a cell that can bind to a specific molecule and produce a specific biological response
162
recessive
an allele that does not produce a characteristic effect when present with a dominant allele; the trait is expressed only under homozygous conditions
163
ribosomal RNA (rRNA)
the kind of RNA that constitutes the ribosomes and provides the site for translation
164
ribosome
a protein-ribosomal RNA complex that is the site of protein synthesis (or translation) in the cell
165
RNA (ribonucleic acid)
a family of nucleic acids that are transcribed from DNA and play various essential roles in the synthesis of proteins
166
sex chromosomes
the chromosomes that influence sex determination, e.g. XX and XY in humans
167
sex linked
the pattern of inheritance that is determined by genes located on the sex chromosomes of organisms
168
sexual reproduction
the creation of genetically diverse offspring by the fusion of two haploid gametes
169
sickle cell anemia
a homozygous recessive genetic disease that is caused by a single mutation of the hemoglobin gene; the mutation results in distortions in the shape of red blood cells and multiple symptoms
170
silent mutation
a type of mutation that does not change the sequence of amino acids and thus does not change the trait controlled by the affected gene
171
single nucleotide polymorphism (SNP)
a genetic variation in a single nucleotide base in DNA that results in a difference between individuals
172
social Darwinism
a doctrine that applies to the principles of "survival of the fittest" in the context of human societies
173
somatic cell
all the cells of the body that do not belong to the germ line
174
speciation
the evolution and formation of new species
175
species
the basic unit of biological classification composed of individuals that can interbreed and produce fertile offspring (the biological species concept)
176
spindle fibers
an array of microtubules emanating from both poles of a dividing cell during cell division and playing a role in the movement of chromosomes at nuclear division; it is named for its spindle-like shape
177
stem cell
an unspecialized cell that can divide infinitely and be induced to become any specialized cell in a multi-cellular organism
178
steroids
any of a family of lipids with ring structures and that primarily function as hormones
179
stop codon
a triplet genetic code in mRNA that signifies the termination of translation
180
sum (addition) rule
the probability that two independent events A or B will happen is the sum of the probability of each event
181
sympatric speciation
the formation of two species that occurs without geographic seperation
182
synapses
in cell division, the point at which two homologous chromosomes attach during prophase of meiosis I
183
taxonomy
the scientific discipline of naming and classifying organisms
184
Tays-Sachs disease
a rare hereditary disease caused by the mutation of a gene involved in lipid metabolism, which results in defective nerve cells and degeneration of the central nervous system
185
telophase
the end stage of mitosis when chromosomes begin to disperse and the nuclear envelope reforms
186
tetrad
during prophase I of meiosis, the association of a pair of homologous chromosomes or four chromatids
187
totipotent
possessing all the genetic information and other capacities necessary to form an entire individual
188
trait
a variant of a characteristic found in a population
189
transcription
the process by which RNA is synthesized from a DNA template
190
transfer RNA (tRNA)
a type of RNA that contains an anticodon and brings the amino acids to the ribosomes to make proteins
191
transgene
a gene that is transferred from one species to another species using recombinant DNA technologies
192
translation
the process by which a protein is synthesized at a ribosome, using messenger RNA code and transfer RNA to carry the amino acids
193
true-breeding
a genetic cross in which the same trait appears every time from homozygous parents
194
vector
in molecular biology, a plasmid or virus that carries an inserted piece of DNA into a bacterium for cloning purposes
195
X-ray crystallography
a technique in which the shape of a crystallized molecule is determined using X-rays
196
zygote
the diploid cell formed by the fertilization of male and female gametes
