Ch 17 from gene to protein

the process by which DNA directs the synthesis of proteins or soemtimes just RNAs

Gene expression

the link between genotype and phenotype

proteins created through RNA

bridge between DNA and protein synthesis

RNA

what are the differences between DNA and RNA?

RNA contains ribose instead of deoxyribose as its sugar, and has the nitrogenous basae uracil rather than thymine

nuclease

an enzyme that cuts DNA or RNA, either removing one or a few bases or hydrolizing the DNA or RNA completely into its component nucleotides

a dense region of DNA in a prokaryotic cell

nucleoid

nucleolus

a specialized structure in hte nucleus, consisting of chromatin regions containingn ribosomal RNA genes along with ribosomal proteins imported from the cytoplasmic site of rRNA synthesis and ribosomal subunit assembly

the basic, bead-like unit of DNA packing in eukaryotes, consisting of a segment of DNA wound around a protein core composed of two copies of each of four types of histone

nucleosome

Nucleotide

the building block of a nucleic acid consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group

Okazaki Fragment

a short segment of DNA synthesized away from the replkication fork on a template strand during DNA replication, many of which are joined together to make up the lagging strand of newly synthesized DNA

monomers in DNA or RNA

four types of nucleotides, which differ in their nitrogenous bases, genes are hundreds of thousands of nucleotides long

Transcription

synthesis of RNA under the direction of DNA (template strand). The RNA is a faithful complementary strand and can be send many places like my transcript.

mRNA

messenger RNA. It is sent out from Transcription, carrying a genetic message from the DNA to the protein-synthesizing mahcinery of the cell

Translation

the synthesis of a polypeptide, which occurs under the direction of mRNA. The cell must translate the base sequence of an mRNA molecule into the Amino acid sequence of a polypeptide. Done in ribosomes.

genetic flow of information in bacteria and eukaryotes

bacteria do not have a nucleus, so their DNA is not segregated from ribosomes etc, which allows for translation to begin while transcription is still in progress. This is separate in a eukaryote.