Life Science ePrep Course
Sample Key Terms
(for DNA Structure and Functions)
- Bacteriophage: virus that infects bacteria.
- DNA sequence: order of nucleotides in a strand of DNA.
- Autosome: a chromosome that is the same in males and females.
- Centromere: of a duplicated eukaryotic chromosome, constricted region where sister chromatids attach to each other.
- Chromosome: a structure that consists of DNA and associated proteins; carries part or all of a cell’s genetic information.
- Chromosome number: the total number of chromosomes in a cell of a given species.
- Diploid: having two of each type of chromosome characteristic of the species (2n).
- Histone: type of protein that structurally organizes eukaryotic chromosomes.
- Karyotype: image of an individual’s set of chromosomes arranged by size, length, shape, and centromere location.
- Nucleosome: a length of DNA wound twice around a spool of histone proteins.
- Sex chromosome: member of a pair of chromosomes that differs between males and females.
- Sister chromatids: the two attached DNA molecules of a duplicated eukaryotic chromosome.
- DNA ligase: enzyme that seals gaps in double-stranded DNA.
- DNA polymerase: DNA replication enzyme. Uses one strand of DNA as a template to assemble a complementary strand of DNA from nucleotides.
- DNA replication: process by which a cell duplicates its DNA before it divides.
- Nucleic acid hybridization: convergence of complementary nucleic acid strands. Arises because of base-pairing interactions.
- Primer: short, single strand of DNA that base pairs with a targeted DNA sequence.
- Semiconservative replication Describes the process of DNA replication, which produces two copies of a DNA molecule: one strand of each copy is new and the other is parental.
- Mutation: permanent change in the nucleotide sequence of DNA.
- Differentiation: process by which cells become specialized during development; occurs as different cells in an embryo begin to use different subsets of their DNA.
- Reproductive cloning: technology that produces genetically identical individuals.
- Somatic cell nuclear transfer (SCNT): reproductive cloning method in which the DNA of an adult donor’s body cell is transferred into an unfertilized egg.
- Therapeutic cloning: the use of SCNT to produce human embryos for medical purposes.