Genetics Terms Flashcards
semiconservative replication
Replication that produces two copies where each contains one of the original strands and one new strand.
mRNA
A subtype of RNA that carries a portion of the DNA code to other parts of the cell for
processing.
tRNA
Is a type of RNA molecule that helps decode a messenger mRNA sequence into a protein.
They function at specific sites in the ribosome during translation, which is a process that
synthesizes a protein from an mRNA molecule.
translation
The process in which cellular ribosomes create proteins.
transcription
It is the process of transcribing or making a copy ofgeneticinformation stored in
aDNAstrand into acomplementary strand mRNA.
anticodon
A sequence of three nucleotides forming a unit of genetic code in a transfer RNA molecule,
corresponding to a complementary codon in messenger RNA.
ribosome
A minute particle consisting of RNA and associated proteins, found in large numbers in the
cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize
polypeptides and proteins.
DNA replication
The biological process of producing two identical replicas of DNAfrom one
originalDNAmolecule.
helicase
Enzymes that are essential during DNA replication because they separate double-stranded
DNA into single strands allowing each strand to be copied.
chromatid
Each of the two threadlike strands into which a chromosome divides longitudinally during cell division. Each contains a double helix of DNA.
polymerase
An enzyme that brings about the formation of a particular polymer, especially DNA or RNA
spindle fibre
Microtubules that move chromosomes during cell division.
aster
A star-shaped cluster of microtubules.
disjunction
(segregation)
When chromosomesmove apart toward the opposite poles of thecellinanaphase.
cytokinesis
The division of the rest of the cell’s cytoplasm and organelles at the end of cell
division.
synapsis
The fusion of chromosome pairs at the start of meiosis.
crossing over
The exchange of genes between homologous chromosomes, resulting in a mixture of
parental characteristics in offspring.
centriole
A minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and
involved in the development of spindle fibers in cell division.
double helix
The term refers to the structure formed by double-stranded molecules of nucleic acids.
nucleotide
The basic structural unit of nucleic acids such as DNA and RNA.
nucleic acid
A complex organic substance present in living cells, especially DNA or RNA, whose molecules
consist of many nucleotides linked in a long chain.
hydrogen bond
A weak bond between two molecules.
phosphodiester bond
Thestrong covalent bondformed between the deoxyribose in DNA and ribose in RNA.
amino acid
A simple organic compound containing both a carboxyl (—COOH) and an amino (—NH 2 ) group.
codon
A sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA
molecule.
synonymous codons
Codons that code for the same amino acids. For example, UUU and UUC code for the same
amino acid-phenylalanine.
fertilization
The fusion of male and female gametes to form a zygote.
chromosomes
A threadlike structure of nucleic acids and protein found in the nucleus of most living cells,
carrying genetic information in the form of genes.
inheritance
The process of genetic transmission of traits from parents to offspring.
histones
Any of a group of basic proteins found in chromatin (a chromosome).
homologous chromo.
Chromosomes that have the exact same genes - although may have different alleles of these
genes, shape and size. They pair up during meiosis.
karyotype
The complete set of genes or genetic material present in a cell or organism. Arranged in
homologous pairs from longest to shortest; sex chromosome at the end.
somatic cell
Any cell of a living organism other than the reproductive cells.
gene
A region of DNA that encodes a functional RNA or protein product, and is the molecular unit
of heredity.
diploid
A cell containing two complete sets of chromosomes, one from each parent.
genome
The term used for the complete set of chromosomes in a species, or an individual organism.
gamete
A mature haploid male or female germ cell that is able to unite with another of the opposite
sex in sexual reproduction to form a zygote.
promoter region
Is aregionof DNA that initiates transcription of a particular gene.
haploid
A cell having a single set of unpaired chromosomes.
stop codon
A nucleotide triplet within messenger RNA that signals a termination of translation.
protein
Any nitrogenous organic compounds that consist of large molecules composed of one or more
long chains of amino acids and are an essential part of all living organisms, especially as
structural components of body tissues such as muscle, hair, collagen, etc., and as enzymes and
antibodies.
