Glossary Terms Flashcards

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1
Q

Adaptation

A

an inherited characteristic that improves an organism’s ability to survive and reproduce in a particular environment

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2
Q

agglutination

A

the clumping together of red blood cells or microorganisms in the presence of a specific antibody

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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

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4
Q

allele

A

one of the alternative forms of a gene

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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

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6
Q

amino acid

A

the basic building block of proteins

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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

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8
Q

amoeboid

A

having no definite shape, resembling the form or type of movement of an amoeba

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9
Q

anaphase

A

the third stage of mitosis when sister chromatids split and move toward opposite poles of the cell

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10
Q

antibody

A

a protein produced by immune cells that binds to a specific antigen to neutralize its effects

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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

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12
Q

antigen

A

a substance that evokes the production of an antibody

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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

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14
Q

ATP (adenosine triphosphate)

A

a temporary energy storage molecule for most cells

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15
Q

autophagy

A

a controlled digestion process in which a cell’s own subcellular organelles are broken down and recycled

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16
Q

autosome

A

any eukaryotic chromosome other than a sex chromosome

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17
Q

bacteriophage

A

a virus that infects bacteria

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18
Q

binary fission

A

a type of asexual reproduction in which a parent cell divides into two genetically identical daughter cells

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19
Q

binomial theorem

A

the theorem that describes the expansion of any power of a binomial, that is, (a+b)^m

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20
Q

biopsy

A

the removal of a piece of tissue from a living body for diagnostic studies

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21
Q

biotechnology

A

the use of molecular techniques in living organisms to manufacture useful products

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22
Q

blending inheritence

A

a historically influential but factually incorrect notion that organisms contain a blend of traits from their parents

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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

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24
Q

cancer

A

a disease caused by abnormally rapid proliferation of body cells

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25
Q

carbohydrate

A

a sugar that contains carbon, hydrogen, and oxygen in the ratio 1:2:1 (CH2O)

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26
Q

carrier

A

in genetics, an individual who is heterozygous for a particular trait

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27
Q

cell

A

the basic structural and functional unit of living organisms

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28
Q

cell cycle

A

a series of orderly events a eukaryotic cell goes through, from a dividing parent cell to two daughter cells

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29
Q

cell theory

A

the theory that cells are the basic unit of life and that all cells arise from preexisting cells

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30
Q

cellular respiration

A

the metabolic pathways by which food molecules are broken down and energy is released and harvested by the cell

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31
Q

central vacuole

A

a large organelle in plant cells that stores the waste products of metabolism, maintains turgor pressure, and maintains growth

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32
Q

Centrifugation

A

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

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33
Q

Centriole

A

A structure in animal cells composed of bundles of microtubule triplets during cell division

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34
Q

Centromere

A

A region where sister chromatids (duplicated chromosomes) are joined and to which spindle fibers are attached during cell division

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35
Q

Chorionic villus sampling (CVS)

A

A procedure in which a sample of the fetal chorionic villa (part of the placenta) is removed for genetic testing

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36
Q

Chromatid

A

One of a pair of identical chromosomes after DNA replication in the cell cycle

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37
Q

Chromatin

A

A dispersed DNA-protein complex that makes up eukaryotic chromosomes

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38
Q

Chromatography

A

A laboratory procedure used to separate and isolate substances in a mixture based on the physical or chemical properties of the constituents

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39
Q

Chromosome

A

A complex structure in the nucleus of eukaryotes or in the nucleoid region of prokaryotes that is comprised of DNA

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40
Q

cilia (sing. cilium)

A

short microscopic projections of the cell surface specialized for locomotion

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41
Q

cleavage

A

the first few cell divisions of an animal zygote

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42
Q

coated pit

A

a specialized depression on the surface of a cell membrane, formed as a result of receptor-mediated endocytosis

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43
Q

co-dominance

A

a type of inheritance in which two separate alleles at a locus are equally expressed and produce different phenotypic traits

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44
Q

codon

A

a triplet of nucleotides in messenger RNA coding for a specific amino acid; the basic unit of the genetic code

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45
Q

conjugation

A

the transfer of genetic material by joining two bacteria or protists

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46
Q

cystic fibrosis

A

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

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47
Q

cytokinesis

A

the cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separation into two daughter cells

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48
Q

cytological

A

relating to the science of cytology, a sub-discipline of biology that studies the microscopic structure of cells

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49
Q

cytoplasm

A

the content of a cell inside the plasma membrane and outside the nucleus

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50
Q

cytoskeletal elements

A

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

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51
Q

cytosol

A

the fluid portion of the cytoplasm

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52
Q

deoxyribose

A

a five-carbon sugar that is a building block of DNA and some nucleotides

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53
Q

DNA (deoxyribonucleic acid)

A

the genetic material for all organisms except the RNA virus

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54
Q

dominant

A

describes an allele that determines the phenotype when the genotype is heterozygous

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55
Q

double helix

A

the spiral shape of a double-stranded DNA molecule

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56
Q

duplication

A

the production of a second copy of a particular sequence of DNA

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57
Q

electrophoresis

A

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

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58
Q

embryonic

A

related to an embryo, or being in the state of an embryo

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59
Q

endocytosis

A

a process by which liquids or solid particles are taken up by a cell through invagination of the plasma membrane

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60
Q

endometrium

A

the inner epithelial lining of the uterus

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61
Q

endoplasmic reticulum

A

a network of tubules that is part of the endomembrane system in eukaryotic cells specializing in the synthesis and modification if biological molecules

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62
Q

endosymbiosis

A

the theory that ancient large eukaryotic cells ingested small prokaryotes, which became subcellular organelles (such as mitochondria and chloroplasts) of the large host cell

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63
Q

epigenetics

A

the scientific study of changes in the inheritance of traits that occur without changes in the DNA sequence

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64
Q

epistasis

A

an interaction between two genes in which one gene alters the expression or effect of another gene

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65
Q

erythropoietin

A

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

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66
Q

eugenics

A

the study or practice of altering a population, especially of humans, by controlling fertility and selective breeding for desirable traits

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67
Q

evolution

A

the process of change by which new species develop from preexisting ancestral species over time

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68
Q

exocytosis

A

a process by which a vesicle within a cell fuses with the plasma membrane and releases its contents to the outside

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69
Q

exon

A

the nucleotide sequence of a gene that codes for a protein

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70
Q

familial hypercholesterolemia

A

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

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71
Q

flagella (sing. flagellum)

A

long, whip-like appendages that propel and move cells

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72
Q

functional genomics

A

the branch of genomics that analyzes the biological function of genes and their products

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73
Q

gemmule

A

a hypothetical particle postulated to be the hereditary unit (now recognized as incorrect) in the theory of pangenesis

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74
Q

gene

A

a unit of hereditary consisting of a specific sequence of nucleotides in DNA (or RNA in some viruses)

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75
Q

gene expression

A

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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76
Q

genetic code

A

the code relating nucleotide triplets in messenger RNA (or DNA) to amino acids in proteins

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77
Q

genetic drift

A

a change in the allele frequency in a population that occurs by chance

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78
Q

genetics

A

a sub-discipline of biology that studies genes and heredity

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79
Q

genome

A

the full set of DNA in a cell or organism

80
Q

genomic DNA

A

the DNA constituting the genome of a cell or an organism, as distinguished from extra chromosomal DNAs, such as plasmids

81
Q

genotype

A

the genetic makeup (set of alleles) of an organism

82
Q

germ cell

A

a reproductive cell (gamete), or one of its precursors, of a multicellular organism

83
Q

germ line

A

the lineage of cells from which gametes are derived

84
Q

glycoprotein

A

a protein with one or more chains sugar (carbohydrate) attached

85
Q

golgi apparatus

A

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
Q

Hardy-Weinberg equilibrium

A

the condition when a population is not evolving

87
Q

Hardy-Weinberg theorem

A

the principle that allele frequencies and genotypes in a population remain constant over generations

88
Q

heredity

A

the process by which characteristics are passed from one generation to the next

89
Q

heritable

A

capable of being passed down from one generation to the next

90
Q

heterozygous

A

having two different alleles at a gene locus for a particular trait

91
Q

homologous chromosomes

A

a pair of chromosomes with the same set of genes, each derived from one parent

92
Q

homozygous

A

having identical alleles at a gene locus for a particular trait

93
Q

human immunodeficiency virus (HIV)

A

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
Q

hybrid

A

the offspring of a cross between two species

95
Q

hybridize

A
  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
Q

hydrophobic

A

having a tendency to repel water and not dissolve or mix with water

97
Q

hypothesis

A

a tentative explanation or answer to a question that can be tested and falsified by the scientific method

98
Q

incomplete dominance

A

a pattern of inheritance in which the heterozygous phenotype is intermediate between two homozygous phenotypes

99
Q

insulin

A

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
Q

insulin-resistance

A

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
Q

interferon

A

a defensive protein produced by virus-infected cells that is capable of increasing the resistance of other cells to the virus

102
Q

intermediate filaments

A

one of three types of cytoskeletal elements in eukaryotic cells involved in maintaining the cell shape and stabilizing organelles

103
Q

intron

A

a part of the nucleotide sequences of a gene that does not code for a protein

104
Q

karyotyping

A

a set of photographs displaying paired chromosomes by size and shape

105
Q

kinetochore

A

the specialized region on the centromere of the chromatid to which microtubules attach during cell division

106
Q

law of dominance

A

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
Q

law of independent assortment

A

one of the rules of inheritance formulated by Mendel which states that nonhomologous chromosomes are sorted independently from each other during gamete formation

108
Q

law of segregation

A

one of the rules of inheritance formulated by Mendel which states that alleles or homologous chromosomes are segregated during gamete formation

109
Q

linked genes

A

genes on the same chromosome that share a close association such that they tend to be inherited together

110
Q

lipid

A

one of a group of nonpolar and hydrophobic molecules consisting mainly of a hydrocarbon chain

111
Q

low-density lipoprotein (LDL) cholesterol

A

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
Q

lysosome

A

an organelle specializing in digestion in animal cells and some protists

113
Q

macroevolution

A

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
Q

meiosis

A

a special type of cell division that occurs in sexually reproducing species during which one diploid germ cell produces four haploid gametes

115
Q

messenger RNA (mRNA)

A

a type of RNA that is transcribed from DNA and acts as the message for the translation of proteins

116
Q

metaphase

A

the second stage of mitosis when chromosomes with sister chromatids line up along the metaphase plate

117
Q

microevolution

A

evolutionary change on a small scale that is defined as changes in gene frequencies in a population over time

118
Q

microfilaments

A

one of three types of cytoskeletal elements in eukaryotic cells involved in maintaining the cell shape and cell movement

119
Q

micro RNA (miRNA)

A

a class of short (~22 nucleotides) RNA involved in post-transcriptional regulation

120
Q

microtubule organizing centers (MTOC)

A

the region or structure where spindle microtubules are organized during cell division

121
Q

microtubules

A

one of three types of cytoskeletal elements in eukaryotic cells involved in transporting organelles and as a structural component of cilia and flagella

122
Q

mitochondrial DNA

A

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
Q

mitosis

A

a type of cell division in multicellular organisms that produces genetically identical cells

124
Q

modern synthesis

A

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
Q

multipotent

A

having the potential to form a set of multiple cell types in the body

126
Q

mutation

A

a change in the nucleotide sequence of DNA in an organism

127
Q

natural selection

A

a process in which individuals with certain heritable traits are more likely to survive and reproduce in a particular environment

128
Q

nonpolar

A

molecules that have equal sharing of electrons

129
Q

nucleic acid

A

a polymer consisting of many mononucleotides; e.g., DNA and RNA

130
Q

nuclein

A

a crude mixture of nucleic acids and many proteins extracted from a cell

131
Q

nucleoid

A

the region containing all or most of the genetic material of prokaryotic cells

132
Q

nucleolus

A

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
Q

nucleotide

A

a building block of DNA and RNA which consists of a phosphate and a five-carbon sugar with a nitrogenous base attached

134
Q

nucleus

A

a membrane-bound subcellular structure where DNA is located in eukaryotic cells

135
Q

oncogene

A

a gene that stimulates cell proliferation or causes cancer if mutated or abnormally activated

136
Q

oogonia (sing. oogonium)

A

undifferentiated female germ cells that give rise to oocytes through meiosis

137
Q

organelle

A

a specialized structure that performs a particular function function in the cytoplasm of eukaryotic cells

138
Q

organism

A

a living thing

139
Q

pangenesis

A

an incorrect theory of heredity that posited that a reproductive cell contains gemmules derived from individual cells from different parts of the organism

140
Q

pedigree

A

a chart of a family tree depicting the pattern of transmission of a particular trait

141
Q

phagocytosis

A

a type of endocytosis in which solid particles are ingested by a cell

142
Q

phenotype

A

the physical or biochemical characteristics of an organism that are the result of interaction between genotype and the environment

143
Q

phospolipid

A

a lipid molecule containing fatty acids and a phosphate group that is an important constituent of membranes

144
Q

photosynthesis

A

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
Q

pinocytosis

A

a type of endocytosis in which the cell takes in fluid and dissolved substances by invagination of the plasma membrane

146
Q

placenta

A

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
Q

plasma membrane

A

the border of all cells that serves as a selectively permeable barrier and site of communication with the external environment

148
Q

pleiotropy

A

occurs when a single gene can determine more than one distinct phenotype effect

149
Q

pluripotent

A

having the potential to form any type of cell in the body

150
Q

pnuemonia

A

inflammation of the lungs usually caused by infection with viruses or bacteria

151
Q

polygenic

A

a pattern of inheritance in which a single phenotypic trait is determined by the additive effect of multiple genes

152
Q

polymerase chain reaction (PCR)

A

a molecular biology technique in which DNA sequences are amplified for the purpose of research, forensics, or medicine

153
Q

polyploidy

A

having more than two sets of genes and chromosomes

154
Q

population genetics

A

a sub-discipline of genetics that studies the processes influencing gene frequencies in a population

155
Q

primer

A

a strand of nucleic acid, usually RNA, which is complementary to a given DNA sequence for DNA replication

156
Q

product (multiplication) rule

A

a formula use to find the derivatives of products of two or more functions

157
Q

prokaryotic cell

A

a cell that lacks a distinct nucleus and other subcellular organelles

158
Q

prophase

A

the first stage of mitosis when chromosomes with sister chromatids condense and the nuclear envelope disappears

159
Q

protein

A

a macromolecule made up of a sequence of amino acids that performs various functions in a cell

160
Q

Punnet square

A

a diagram used to predict the results of a genetic cross

161
Q

receptor

A

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
Q

recessive

A

an allele that does not produce a characteristic effect when present with a dominant allele; the trait is expressed only under homozygous conditions

163
Q

ribosomal RNA (rRNA)

A

the kind of RNA that constitutes the ribosomes and provides the site for translation

164
Q

ribosome

A

a protein-ribosomal RNA complex that is the site of protein synthesis (or translation) in the cell

165
Q

RNA (ribonucleic acid)

A

a family of nucleic acids that are transcribed from DNA and play various essential roles in the synthesis of proteins

166
Q

sex chromosomes

A

the chromosomes that influence sex determination, e.g. XX and XY in humans

167
Q

sex linked

A

the pattern of inheritance that is determined by genes located on the sex chromosomes of organisms

168
Q

sexual reproduction

A

the creation of genetically diverse offspring by the fusion of two haploid gametes

169
Q

sickle cell anemia

A

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
Q

silent mutation

A

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
Q

single nucleotide polymorphism (SNP)

A

a genetic variation in a single nucleotide base in DNA that results in a difference between individuals

172
Q

social Darwinism

A

a doctrine that applies to the principles of “survival of the fittest” in the context of human societies

173
Q

somatic cell

A

all the cells of the body that do not belong to the germ line

174
Q

speciation

A

the evolution and formation of new species

175
Q

species

A

the basic unit of biological classification composed of individuals that can interbreed and produce fertile offspring (the biological species concept)

176
Q

spindle fibers

A

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
Q

stem cell

A

an unspecialized cell that can divide infinitely and be induced to become any specialized cell in a multi-cellular organism

178
Q

steroids

A

any of a family of lipids with ring structures and that primarily function as hormones

179
Q

stop codon

A

a triplet genetic code in mRNA that signifies the termination of translation

180
Q

sum (addition) rule

A

the probability that two independent events A or B will happen is the sum of the probability of each event

181
Q

sympatric speciation

A

the formation of two species that occurs without geographic seperation

182
Q

synapses

A

in cell division, the point at which two homologous chromosomes attach during prophase of meiosis I

183
Q

taxonomy

A

the scientific discipline of naming and classifying organisms

184
Q

Tays-Sachs disease

A

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
Q

telophase

A

the end stage of mitosis when chromosomes begin to disperse and the nuclear envelope reforms

186
Q

tetrad

A

during prophase I of meiosis, the association of a pair of homologous chromosomes or four chromatids

187
Q

totipotent

A

possessing all the genetic information and other capacities necessary to form an entire individual

188
Q

trait

A

a variant of a characteristic found in a population

189
Q

transcription

A

the process by which RNA is synthesized from a DNA template

190
Q

transfer RNA (tRNA)

A

a type of RNA that contains an anticodon and brings the amino acids to the ribosomes to make proteins

191
Q

transgene

A

a gene that is transferred from one species to another species using recombinant DNA technologies

192
Q

translation

A

the process by which a protein is synthesized at a ribosome, using messenger RNA code and transfer RNA to carry the amino acids

193
Q

true-breeding

A

a genetic cross in which the same trait appears every time from homozygous parents

194
Q

vector

A

in molecular biology, a plasmid or virus that carries an inserted piece of DNA into a bacterium for cloning purposes

195
Q

X-ray crystallography

A

a technique in which the shape of a crystallized molecule is determined using X-rays

196
Q

zygote

A

the diploid cell formed by the fertilization of male and female gametes