Genetics Vocabulary Flashcards Preview

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Flashcards in Genetics Vocabulary Deck (32):
1

Nucleotide

A compound consisting of a nucleoside linked to a phosphate group. Nucleotides form the basic structural unit of nucleic acids such as DNA.

2

Base pairing

Any of the pairs of nucleotides connecting the complementary strands of a molecule of DNA or RNA and consisting of a purine linked to a pyrimidine by hydrogen bonds. The base pairs are adenine-thymine and guanine-cytosine in DNA, and adenine-uracil and guanine-cytosine in RNA or in hybrid DNA-RNA pairing.

3

DNA polymerase

DNA polymerase (DNAP) is a type of enzyme that is responsible for forming new copies of DNA, in the form of nucleic acid molecules. Nucleic acids are polymers, which are large molecules made up of smaller, repeating units that are chemically connected to one another.

4

Gene

(in informal use) a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.

5

Messenger RNA

The form of RNA in which genetic information transcribed from DNA as a sequence of bases is transferred to a ribosome.

6

Ribosomal RNA

In molecular biology, ribosomal ribonucleic acid (rRNA) is the RNA component of the ribosome, and is essential for protein synthesis in all living organisms.

7

Transfer RNA

RNA consisting of folded molecules that transport amino acids from the cytoplasm of a cell to a ribosome.

8

Transcription

Transcription is the process by which the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA).

9

RNA polymerase

RNA polymerase, also known as DNA-dependent RNA polymerase, is an enzyme that produces primary transcript RNA. In cells, RNAP is necessary for constructing RNA chains using DNA genes as templates, a process called transcription.

10

Promoter

Definition of Promoter. Promoter: In molecular biology, a site on DNA to which the enzyme RNA polymerase can bind to initiate the transcription of DNA into RNA.

11

Intron

A noncoding segment in a length of DNA that interrupts a gene-coding sequence or non-translated sequence, the corresponding segment being removed from the RNA copy before transcription.

12

Exon

1. The protein-coding region in the DNA.

2. The nucleic acid sequence in the DNA, or RNA transcript following genetic splicing.

13

Codon

A sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule.

14

Translation

During translation, an mRNA sequence is read using the genetic code, which is a set of rules that defines how an mRNA sequence is to be translated into the 20-letter code of amino acids, which are the building blocks of proteins.

15

Anticodon

A sequence of three nucleotides in a region of transfer RNA that recognizes a complementary coding triplet of nucleotides in messenger RNA during translation by the ribosomes in protein biosynthesis.

16

Helicase

Helicases are enzymes that bind and may even remodel nucleic acid or nucleic acid protein complexes.

17

Okazaki Fragments

Okazaki fragments are short DNA formed on the lagging strand during the process of DNA replication.

18

DNA ligase

In molecular biology, DNA ligase is a specific type of enzyme, a ligase, (EC 6.5.1.1) that facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond.

19

Genotype

The genetic constitution of an individual organism.

20

Phenotype

The set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.

21

Allele

One of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.

22

Homozygous

Having the two genes at corresponding loci on homologous chromosomes identical for one or more loci.

23

Heterozygous

The genetics term heterozygous refers to a pair of genes where one is dominant and one is recessive — they're different. Like all words with the prefix hetero, this has to do with things that are different — specifically genes.

24

Dominant

An individual with one dominant and one recessive allele for a gene will have the dominant phenotype. They are generally considered “carriers” of the recessive allele: the recessive allele is there, but the recessive phenotype is not.

25

Recessive

A recessive gene is a gene that is not dominant, but only manifests when a gene of both parents is the same, i.e., homozygous (where both genes are the same as in two genes for blue eyes).

26

Purebred

An animal bred from parents of the same breed or variety.

27

Hybrid

The offspring of two plants or animals of different species or varieties, such as a mule (a hybrid of a donkey and a horse).

28

Gametes

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.

29

Codominance

Codominance is a relationship between two versions of a gene. Individuals receive one version of a gene, called an allele, from each parent. If the alleles are different, the dominant allele usually will be expressed, while the effect of the other allele, called recessive, is masked.

30

Incomplete Dominance

Incomplete dominance refers to a genetic situation in which one allele does not completely dominate another allele, and therefore results in a new phenotype.

31

Sex-Linked Genes

A gene located on a sex chromosome, usually the X-chromosome.

32

Pedigree

A diagram showing the lineage or genealogy of an individual and all the direct ancestors, usually to analyze or follow the inheritance of trait.