BIOLOGY CH13 TEST REVIEW
VOCABULARY
CHAPTER 13: DNA, RNA, and Proteins
The Central Dogma of Biology DNA is transcribed into RNA->RNA is translated into Proteins
Griffith - Discovered the transformation of harmless R strain Bacteria by heat killed S bacteria
Avery – Identified DNA as the transformative agent
Hershey & Chase –Studied bacteriophages and proved DNA was the source of hereditary information
James Watson & Francis Crick deduced the structure of DNA
Rosalind Franklin used x ray crystallography to image the structure of DNA
DNA- Deoxyribonucleic Acid
DNA- is a polymer of Nucleotides- remember a polymer is like a chain of beads
DNA- is made of 2 chains, twisted together and coiled into an alpha double helix
DNA- Double Helix is composed of 2 interconnected nucleotide chains
Nucleotide Chains are composed of a Sugar-Phosphate backbone, with bases in the middle
Phosphodiester bonds join nucleotides
Nucleotide contains 1 Nitrogenous base + 1 phosphate group + 1 sugar
Deoxyribose the sugar in DNA
4 different Nucleotides abbreviated as A, T G, or C
The pyrimidines
-Adenine Guanine
The purines -Cytosine Thymine
Chargraff’s Rules - A binds T, G binds C according to
Hydrogen bonds.- join the bases across the helix
MITOSIS
-Cell division
MEIOSIS
gamete formation
DNA Replication- is semi conservative!
Helicase breaks hydrogen bonds in the middle of the strand, creating a replication fork
DNA Polymerase, creates 2 identical DNA molecules
Transcription- DNA copied to RNA, occurs in nucleus
RNA- A nucleic acid that is similar to DNA, Ribose is the sugar, instead of thymine, URACIL, single
stranded
Steps of Transcription
RNAPolymerase (RNApol)– Unwinds DNA strand and copies it into RNA
Uracil RNA base replacing Thymine
Messenger RNA (mRNA) DNA transcript or copy moves to the ribosome in the cytoplasm (or on the
Rough ER)
Translation (Protein Synthesis) - The Conversion of mRNA to Amino Acids which make up proteins
The Genetic code (ATCG) is translated into a amino acids
CODON- a 3 letter sequence of mRNA that codes for a particular Amino Acid
Amino Acid -the components that make Proteins
tRNA (transferRNA)- the RNA that carries amino acids to the ribosome
Anti-Codon – the 3 letter sequence of tRNA that corresponds to the mRNA CODON
AUG - the start codon
Translation – conversion of mRNA into a Protein
Initiation- Ribosome attaches to mRNA (each 3 bases is called a codon), tRNA brings anticodon and AA
to ribosome
Elongation- More tRNA’s bring more AA’s to ribosome, AA’s connected together to make polypeptides
(by peptide bonds)
Termination- Ribosome reaches a STOP signal on mRNA
Enzymes- the most common type of protein