Bio 4U - Genetics; Protein Synthesis

Complimentary Base Pairing
Purines (A and G) are always paired with pyrimidines (T and C)
2 nm
Diameter of a DNA molecule
DNA Structure
A polymer composed of nucleotide monomers. Antiparalled strands form a double helix turning in a clockwise direction.
Sugar and Phosphate
Make up the backbone of DNA, and provide support for the nitrogenous bases
Phosphodiester Bonds
The bonds between the phosphate and carbon, or the phosphate and hydroxyl; in DNA
Darwin and Mendel
Worked with pea plants to find out that traits are inherited; determined that some traits are recessive and others dominant through cross-pollination
Erwin, 1944; he moved from physics to biology; he thought that genes were made up of proteins
Johann Friedrich, 1869; discovers acidic 'nuclein' in the nucleus, which is later determined to be DNA.
Views in the 1900s
Scientists thought that proteins were everything, and consequently thought that genes were proteins.
Joachim, 1930s; worked with algae to show that the nucleus controls genetic expression
Frederick, 1928; discovered a transforming factor by chance while looking at pneumonia vaccines; he injected mice with good and bad strands of the virus, discovering that something from the bad strand was able to leak out even when it had been denatured, and still affect the mouse.
Oswald T., 1944; realizes that Frederick's transforming factor was DNA
aka. bacteriophage (a virus that infects bacteria); T-2 and T-4 are types that effect E. Coli
Hershey and Chase
Alfred and Martha, 1952; test to see if viruses carry genetic info on DNA or protein; tagged both protein and DNA with different radioactive atoms to see which one carried on inside the cell; DNA was carried on
Wilkins and Franklin
Used x-ray crystallography (beaming an x-ray through DNA) to determine that DNA took on a helical shape
Erwin; analyzed the ATGC ratios in DNA of different species and determined that they were not all 25% ratios, but that A matched T, and C matched G
Watson and Crick
James and Frances, 1953; theoretical biologists who combined lots of ideas to pull ot all together into today's model of DNA
Consist of a phosphate group, nitrogenous bases, and deoxyribose sugar
Hydrogen Bonds
Connect one nucleotide to another nucleotide
Semiconservative Replication
Each DNA molecule is composed of one parent strand and one newly synthesized stand
DNA Helicase
The enzyme that unwinds double-helical DNA by disrupting hydrogen bonds
The pairing of complementary strands of DNA through hydrogen bonding
Single-stranded binding proteins; proteins that keep separate strands of DNA apart
DNA gyrase
The bacterial enzyme that releives the tension produced by the unwinding of DNA during replication
Replication Fork
The region where the enzymes replicating a DNA molecule are bound to untwisted, single-stranded DNA
Replication Bubble
The region where two replication forks are in close proximity to eachother, producing a bubble in the replicating DNA
DNA Polymerase III
The enzyme responsible for synthesizing complementary strands of DNA during replication
Deoxyribonucleoside triphosphates
Nucleotides; molecules composed of a deoxyribose sugar bonded to three phosphate groups and a nitrogenous base
RNA Primer
Annealed to a region of single stranded DNA in order to initate replication
The enzyme that builds RNA primers
Leading Strand
The new strand of DNA that is synthesized continuously during DNA replication.
Lagging Strand
The new strand of DNA that is synthesized in short fragments, which are later joined together
Okazaki Fragments
Short fragments of DNA that are a result of the synthesis of the lagging strand during DNA replication
DNA Polymerase I
The enzyme that removers RNA primers and replaces the with the appropriate nucleotides during replication
DNA Ligase
The enzyme that joins DNA fragments together
Variable Number Tandem Repeats; repeated base pair sequences; 3 types: telomeres, centromeres, pseudogenes
Non-coding DNA at ends of chromosomes to protect genetic material
Repetitive DNA attaches to spindle fibres
2 types: LINEs and SINEs (long/short Interspersed Nuclear Elements)
Proteins; 8 of these in one nucleosome
Restriction Endonucleases
Molecular scissors, cut DNA at specific base-pair sequences
Sticky Ends
Overhang produced after DNA bonds are broken by restriction enzymes
Blunt Ends
DNA ends are fully paired after being cut by restriction enzymes
Enzyme thats adds a methyl group to a nucleotide in order to prevent it from being 'cut'
Gel Electrophoresis
Separates DNA based on different fragment sizes, and the fact that DNA is negatively charged