Chapter 13 Vocabulary

1.     transformation         process in which one strain of bacteria is changed by a gene or genes from another strain of bacteria

2.     bacteriophage           virus that infects bacteria

3.     nucleotide      monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base

4.     base pairing   principle that bonds in DNA can form only between adenine and thymine and between guanine and cytosine

5.     chromatin       granular material visible within the nucleus; consists of DNA tightly coiled around proteins

6.     histone            protein molecule around which DNA is tightly coiled in chromatin

7.     replication      copying process by which a cell duplicates its DNA

8.     DNA polymerase      enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule

9.     gene     sequence of DNA that codes for a protein and thus determines a trait

10.      messenger RNA (mRNA)               RNA molecule that carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell

11.      ribosomal RNA (rRNA)    type of RNA that makes up the major part of ribosome

12.      transfer RNA (tRNA)       type of RNA molecule that transfers amino acids to ribosomes during protein synthesis

13.      transcription          process in which part of the nucleotide sequence of DNA is copied into a complementary sequence in RNA

14.      RNA polymerase   enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription

15.      promoter     region of DNA that indicates to an enzyme where to bind to make RNA

16.      intron               sequence of DNA that is not involved in coding for a protein

17.      exon  expressed sequence of DNA ; codes for a protein

18.      codon            three-nucleotide sequence on messenger RNA that codes for a single amino acid

19.      translation  decoding of a mRNA message into a polypeptide chain

20.      anticodon    group of three bases on a tRNA molecule that are complementary to an mRNA codon

21.      mutation      change in a DNA sequence that affects genetic information

22.      point mutation      gene mutation involving changes in one or a few nucleotides

23.      frameshift mutation        mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide

24.      polyploidy   condition in which an organism has extra sets of chromosomes

25.      operon          group of genes operating together

26.      operator       region of chromosome in an operon to which the repressor binds when the operon is "turned off"

27.      differentiation       process in which molecule tend to move from an area where they are more concentrated to an area where they are less concentrated

28.      hox gene      series of genes that controls the differentiation of cells and tissues in an embryo