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What is Genetic Material
DNA, which was first isolated by Friedrich Miescher in 1869
Structure solved in 1950s by Watson & Crick
DNA is a polymer of a series of nucleotides. Each nucleotide differs by the nitrogenous base it contains (A,C,G,T)
What are genomes
All of the organism’s DNA-based genetic instructions
Composed of genes
What are genes
DNA instructions for making proteins
promoter at beginning of gene, followed by open reading frame which contains series of codons which encode amino acids, then end by a stop codon
What is central dogma
DNA (gene) → (transcription) → RNA (RNA polymerase) → (translation) → protein (Ribosomes)
What are the three main different types of RNA
mRNA - messenger RNA
tRNA - transfer RNA
rRNA - ribosomal RNA
What is RNA
Primary structure of RNA is similar to DNA
RNA, like DNA, can be single or double stranded, linear or circular
Unlike DNA, RNA can exhibit different confirmations, which permit the RNAs to carry out specific functions in the cell
Contains uracil (U) instead of thymine (T)
What is gene expression and how does it take place
the process of using DNA information to make mRNA and proteins
RNA polymerases look for promoter sequences to recognize beginning of genes
Prokaryotes use positive and negative regulation for transcription
Eukaryotes are complex, they have promoter sequences and enhancers which can lead to complex expression
What are open reading frames
Long stretches of DNA uninterrupted by stop codons tend to be protein coding
Genes are ORFs and additional regulatory information
Translation of RNA to protein starts at Met, or start codon (AUG)
Continues until a stop codon is reached (UAG, UAA, UGA)
Prokaryote vs Eukaryote genes
Prokaryote genes :
transcription initiation, coding region, and termination signal
Eukaryotes :
transcription initiation, coding region (exons) / introns (not coded), and termination signal
Genome structure
Can be circular, or linear
Eukaryote chromosomes are linear
Prokaryote chromosomes are circular (also plasmids, virus’s, organelles, etc)
Four levels of protein structure
primary (linear amino acid sequence),
secondary (beta sheets and alpha helices, form first when linear sequence is forming),
tertiary (global 3D conformation, and called the native state, final and stable), and
quaternary (can be subunit of larger complex, tertiary forming complex with other units)
What is sequencing
Determining the exact nucleotide sequence of DNA
Makes it possible to determine the exact sequence of a gene or the entire genome of an organism
Many methods :
Maxam-Gilbert Method - chemical degradation
Dideoxy (Sanger) Method - chain termination
Next-generation (high-throughput) - many types
What is Dideoxy (Sanger) Sequencing
Uses DNA sequence as a template, adds a primer and then adds dideoxynucleotides, which are chain terminating. This means that the DNA polyermase is unable to further extend the molecule once the dideoxynucleotides are added to the growing sequence.
You end up with a pool of DNA fragments of different length.
Limited in number of base pairs that can be sequenced in a amount of time
What is Next-gen sequencing
non-Sanger high-throughput DNA sequencing technologies
Many different DNA fragments can be sequenced at the same time, so cost of DNA sequencing has gone down dramatically
Illumina is most common
What is evolution
Changes in inherited characteristics of biological populations over successive generations
Generates diversity of genotype and phenotype
What is point mutation
When one nucleotide mutates into another letter
What is a gene duplication
When an entire gene gets duplicated into another copy in a genome. One of the new copies may diverge into another copy
What is insertion mutation
When nucleotides are added to a gene which they were not previously there
What is deletion mutation
When nucleotides are deleted in a gene which were previously there
What is genetic variation
Mutation drive differences between species
Raw material for evolution to act on
Raw data that we analyze in bioinformatics and much of comp. bio
Where are all these sequences stored
A major source is GenBank / NCBI
Note 
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