AP Biology DNA, RNA and Protein Synthesis

nucleotides

monomers of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base

RNA

A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.

base pairing

Principle that bonds in DNA can form only between adenine and thymine and between guanine and cytosine

RNA polymerase

An enzyme that links ribonucleotides into a growing RNA chain during transcription, based on complementary binding to nucleotides on a DNA template strand

protein synthesis

Forming proteins using ribosomes (RER) based on information in DNA and carried out by RNA

polypeptide

A polymer (chain) of many amino acids linked together by peptide bonds.

amino acids

Building blocks of protein

chromosomes

contain genetic material and are located in the nucleus

mRNA

RNA that attaches to ribosomes in the cytoplasm and specifies the primary structure of a protein; also called messenger RNA.

tRNA

RNA molecules that attach the correct amino acid to the protein chain that is being synthesized at the ribosome of the cell

rRNA

RNA molecules that, together with proteins, make up ribosomes

adenine

A double-ring nitrogenous base found in DNA and RNA. Pairs with Thymine.

thymine

A single-ring nitrogenous base found only in DNA. Pairs with Adenine.

cytosine

A single-ring nitrogenous base found in DNA and RNA. Pair with guanine

guanine

A double-ring nitrogenous base found in DNA and RNA. Binds with cytosine.

uracil

a nitrogen-containing base found in RNA (but not in DNA) and derived from pyrimidine. Binds with adenine

codon

A specific sequence of three adjacent bases on a strand of DNA or RNA that provides genetic code information for a particular amino acid

anticodon

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

intron

A segment of a gene situated between exons that is removed before translation of messenger RNA and does not function in coding for protein synthesis.

exon

A sequence within a primary transcript that remains in the RNA after RNA processing; also refers to the region of DNA from which this sequence was transcribed

promoter

A specific nucleotide sequence in the DNA of a gene that binds RNA polymerase, positioning it to start transcribing RNA at the appropriate place.

ribosome

rRNA and protein molecules that functions in protein synthesis; consists of a large and a small subunit. In eukaryotic cells, is assembled in the nucleolus

translation

The synthesis of a polypeptide using the genetic information encoded in a mRNA molecule. There is a change of "language" from nucleotides to amino acids.

transcription

The synthesis of RNA using a DNA template.

gene mutation

A change in the sequence of the bases in a gene, which changes the structure of the polypeptide that the gene codes for.

chromosomal mutation

A change in the chromosome structure, resulting defects in meiosis

substitution

A type of point mutation; the replacement of one nucleotide and its partner in the complementary DNA strand by another pair of nucleotides.

deletion

a type of gene mutation in which a nucleotide is deleted

insertion

A mutation involving the addition of one or more nucleotides pairs to a gene.

terminator

In bacteria, a sequence of nucleotides in DNA that marks the end of a gene and signals RNA polymerase to release the newly made RNA molecule and detach from the DNA.

bacteriophage

A virus that infects bacteria; also called a phage.

TATA box

A promoter DNA sequence crucial in forming the transcription initiation complex.

Central dogma

RNA nucleotide

RNAi

process in which RNA molecules inhibit gene expression or translation, by neutralizing targeted mRNA molecules.

poly A tail

makes mRNA more stable, prevents its degradation, allows the mRNA molecule to be exported from the nucleus and translated into a protein by ribosomes in the cytoplasm.

GTP cap

used as a recognition signal for ribosomes to bind to the mRNA.

mRNA processing

Addition of cap and tail to the ends of the transcript &
Removal of introns

splice

join, bind, attach

spliceosome

complex of enzymes that serves to splice out the introns of a pre-mRNA transcript

Plasmid DNA

A ring of DNA capable of replicating itself. Found in bacteria commonly.

retrovirus

An RNA virus that reproduces by transcribing its RNA into DNA and then inserting the DNA into a cellular chromosome; an important class of cancer-causing viruses.

reverse transcriptase

a polymerase that catalyzes the formation of DNA using RNA as a template

direction of transcription

5' to 3' direction

rRNA (ribosomal RNA)

type of RNA that makes up the major part of ribosomes

tRNA (transfer RNA)

The form of RNA that carries each amino acid to the ribsome to form the polypeptide chain (protein)

mRNA (messenger RNA)

The form of RNA which is created as a blueprint from DNA; carries instructions for making a protein

Translation location in eukaryotes

ribosome (RER)

Translation location in prokaryotes

cytoplasm

In prokaryotes, when does transcription and translation occur?

at the same time

Transduction in bacteria

DNA is transferred from one bacteria to another by a virus

Transduction