DNA: Structure and Function (Taryn Vandervelde)
DNA Replication & Repair (Stephanie Knol)
Protein Synthesis (Logan Jonker)
Genetic Mutations (Noah Datema)
Restriction Enzymes (Lisa Ludwig)
Genetic Engineering (Marc Vermeulen)
Biotechnology and Health (Chelsea Groen)
The Human Genome Project (Shawna Bos)
Molecular Genetics Review (Tabitha Ravensbergen, Gabby Alkema, Kaelynn Smink, Greydon Nyenhuis)
This animation shows DNA, DNA replication, chromosome structure, and cell division at the level of individual molecules. Incredible!
Friedrich was the first person to discover DNA which he called "Nuclein" in 1868 using pus (primarily using white blood cells) from his patients' bandages.
Griffith discovered that Bacteria can share and transfer genetic info. He did this by combining a viral S-strain and a non viral R-strain, through the "transforming principal" to turn the R-strain into a S-strain.
Watson and Crick were able to deduce the structure by using x-rays and base proportions. Watch the video for more information.
The process of duplicating the cell's DNA which is essential for cell growth, division, and repair.
Process:
Separation
Topimerase cuts and swivels the helicase strand to unwind the spiral.
The helix strand is unwinded and and “unzipped” (pulled apart)
The single strand bonding pairs (SsBp) keeps the strands separated during the process
Elongation
Primase adds short RNA primers which are the staring block to replication
Normal DNA polymerase can’t build a new strand from scratch. It needs a pre-existing nucleic acid to build off of.
The enzyme of RNA primers provide the essential starting point (a 3'-OH group) for DNA polymerase to begin adding DNA nucleotides and copying the template strand
DNA Primase III adds nucleotides to build new strands
Leading vs. lagging strand
Lagging: okazaki fragments ( the new strand is built backwards in sections)
DNA polymerase replaces RNA primers with DNA
Ligase attaches fragments together
DNA polymerase I + II proof read the strand
Terms
-DNA Helicase: Separates Strands
- Replication Fork: where replication happens
- Topoisomerase: Cut+swivel (relieves tension)
- Single stranded binding proteins: Keeps strands apart
- Nucleoside triphosphates: building blocks of DNA ("Letter" - A.C.G.T.)
- RNA primase: enzyme that odds small mRNA piece (double strand for DNA polymerase to work)
- RNA primer: Short pieces of RNA that aid in starting replication
- DNA pol. II: Enzyme that adds new nucleotides to the 3 end of the strand
- leading strand: Strand that can replicate continuously in one piece
- lagging strand: Strand built backwards, piecemeal using Okazaki fragments
- DNA pol. I: Replaces the RNA primers with DNA nucleotides
- DNA ligase: Creates phosphodiester bands to join two fragments together
- DNA poly I and II: Act as proofreaders, cutting out and replacing mismatched
The process of using the information from ONE gene to build a protein for a cell task
Transcription is where you photocopy a gene so you can send it out without risking the original DNA.
Translation is taking the photocopy of the DNA and turning it into a protein via tRNA so it can be used.
Transcriptional:
Transcription factors turn genes on/off.
Post-Transcription:
Introns removed from mRNA, exons spliced together.
Translational:
Rate/frequency of translation, degradation of mRNA.
Post-Translational:
Add functional groups, move around, form 3D shape.
Mutation: an error or change in the DNA sequence, resulting often in a loss of function or information.
When a cell divides it first copies its DNA. If there is damage or a mistake, the DNA code changes, making a mutation. If the cell cannot fix its mistake, the mutation will stay. Mutations can be passed on to further generations if they occur in sperm or egg cells. Mutations can also lead to cancer, genetic diseases (such as cystic fibrosis), or depending on the area they might not have any effect at all. Normally DNA polymerase I and II (proofreaders) can catch these mistakes, but if they cannot fix them it can result in a mutation.
Point Mutation: a change in one DNA base
Substitution, inversion/deletion
This can include effects such as missense, nonsense, silent, and frameshift
Chromosome Mutation: a change in structure or number of chromosomes that can affect many genes, cause diseases or developmental problems
Translocation, transposable elements ("jumping genes"), trinucleotide repeats
Causes:
spontaneous - mistakes in DNA replication
induced - caused by environmental factors (mutagens, chemical/radiation)
Medical:
Biopharming
genetically engineered plants and animals to produce pharmaceuticals (ex. goats milk to stop blood clotting)
pros: lower costs, vaccines can be massed produced, food security
cons: contamination between food crops, possible risk to patients
Genetic screening
testing patients for genetic diseases, also helps I.D people
pros: prevention, diagnosing diseases, informs parents if they will pass a genetic disease to their children
cons: can impact pregnancy decisions, privacy, and treatment choices
Gene therapy
introduction, removal, or alteration of genetic material to treat or prevent diseases
pros: helps with health problems
con: alters a person
Microarrays
compares between unhealthy and healthy cells to research/understand mutations
Agricultural:
Bioremediation
using organisms to clean the environment, removes contaminants naturally
pros: natural, less human imprint on environment, cost effective, able to permanently remove/neutralize contaminants with minimal waste
cons: slow/time consuming, requires constant oversight, limited biodegradable compounds
GMO
genetically altering plants or animals for various purposes
pros: helps protect plants from pests and diseases (less pesticide use), improves nutritional value, enables farmers to use less land, lowers food prices
cons: "playing God", interference with nature, environmental risk, health concerns
Forensics
DNA database
collection of people's DNA stored in computers, can be used to I.D people, solve crimes, and helps with research
pros: proves if someone is guilty or not, helps convict and help with other evidence
cons: there can be lab errors or secondary transfer (no actual direct contact), can result in false convictions
Biopharming
Microarrays
Telomeres
Protective structure at the ends of chromosomes that consist of repetitive DNA sequences and proteins
Centromeres
The constricted region of a chromosome that connects two sister chromatids after DNA replication
Promoters
Specific DNA sequences that bind to proteins like RNA polymerase to initiate gene transcription
Histones
Proteins that provide structural support to DNA, allowing it to be packaged into chromosomes
Nucleosome
The fundamental structure unit, consists of the length of DNA, packages and organizes the long DNA packaging
Supercoiling
Over under twisting of a DNA double helix, crucial for compacting DNA and regulating access to the genetic code
Chromatin
The complex of DNA and proteins (mainly histones) that forms chromosomes within the nucleus
Restriction Enzyme
Act as molecular scissors, cutting any piece of DNA at a specific sequence, targets particular areas of interest. Can be used for DNA fingerprinting, engineering, or sequencing.
DNA Ligase
Enzyme that's used to rejoin pieces of DNA together. Used for Okazaki fragments in genetic engineering
Plasmid
Small loops of DNA used by bacteria to share information such as antibiotic resistance. Genetic engineers can insert genes of interest into a plasmid, used for more production of insulin.
Polymerase Chain Reaction
DNA replication in the lab, each time the cycle repeats the number of copies doubles. Used for crime scenes with not enough DNA. (Typically just replicates the desired sequence)
Gel Electrophoresis
Separates out pieces of DNA based on size, instead of searching the whole strand it can be cut down and isolated to one area. Finds a gene or sequence of interest.
RFLP
Restriction enzymes cut into pieces into different lengths that have different DNA variations. Also known as DNA fingerprinting. Can be used to determine endangered species of be used to match a suspects DNA
DNA Sequencing
Used to determine the order of base pairs
Microarrays
Used to detect any difference in gene expression and function between two cells. Usually used to determine the effects of a disease.
