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Protein Synthesis
Identify the structure and function of DNA, RNA, and proteins.
Recognize diagrams of DNA and RNA, sugars, phosphate groups, nitrogenous bases.
Understand Complimentary base pairing.
How DNA is replicated
Stands for Deoxyribonucleic Acid Type of Nucleic Acid What chromosomes and genes are
made of. Made of repeating nucleotide sub-
units.
2 types of Nitrogen Bases Purines Double ring G & A Pyrimidines Single ring C & U & T
Erwin Chargaff discovered the base pairing rules and ratios for different species.
Adenine pairs with Thymine Cytosine pairs with Guanine
Complementary: bases on one strand match up with the bases on the other strand (A-T and G-C)
Example: Strand 1- ATG GGC Strand 2- Codon: Group of 3 bases
History Rosalind Franklin took first picture
of DNA using a X-ray machine.
The Nobel Prize in Medicine 1962 James Watson & Francis Crick
interpreted the photo and discovered the double helix structure.
Genes: Stretch of DNA that codes for a trait.
The code is the order of the bases (letters).
Genes are hundreds or thousands of bases long.
The genetic code is a sequence of
DNA nucleotides in the nucleus of cells.
During S stage in interphase, DNA replicates itself.
DNA replication is a semi-conservative process.
Semi-conservative means each new piece of DNA is made up of 1 old strand and 1 new strand.
You end up with 2 identical strands
of DNA.
A copy of DNA that goes out into the cytoplasm to tell the cell what to do in order to stay alive
RNA= Ribonucleic Acid You can always make more RNA,
but no more DNA.
Single strand instead of double strand
Ribose instead of deoxyribose Uracil instead of thymine
Definition: RNA is made from 1 gene in DNA
The type of RNA made is called mRNA (messenger RNA) because it sends a message from DNA to the cytoplasm
Transcription Unzip one gene in DNA Match up bases to one side of gene in
DNA mRNA detaches from the DNA mRNA moves out of the nucleus and into
the cytoplasm DNA: GAG AAC TAG TAC ACC TAT CGG
GGG CAT RNA:
mRNA is a message that codes for a protein
Proteins are made in the cytoplasm and then work to keep the cell alive
Proteins are made up of amino acids (small building blocks)
There are 20 different types of amino acids
What causes mutations? A change in the DNA sequence A mistake that’s made during replication
or transcription Can be harmful: diseases or deformities Helpful: organism is better able to
survive Neutral: organism is unaffected If a mutation occurs in a sperm or egg
cell, that mutation is passed on to offspring
If a mutation occurs in a body cell, that mutation affects on the organism and is not passed onto offspring.
Point Mutations or Substitutions: bases are mismatched
Harmful when: a mistake in DNA is carried into mRNA and results in the wrong amino acid.
Not harmful when: a mistake in DNA is carried out into mRNA but still results in the correct amino acid.
Example: Sickle Cell Anemia Types of mutations Frame Shift Mutations: bases are
inserted or deleted. Are usually harmful because a
mistake in DNA is carried into mRNA and results in many wrong amino acids.
Ex.: Crohn’s disease
Chromosomal mutations: Chromosomes break or are lost
during mitosis or meiosis. Broken chromosomes may rejoin
incorrectly Almost always lethal when it occurs
in a zygote. Ex.: hemophilia,a bleeding disorder
Mutagens: anything that causes a change in DNA
Examples: x-rays, UV light, nuclear radiation, asbestos, cigarette smoke
A complex system of enzymes, active in the G2 stage of interphase, serves as a back up to repair damaged DNA before it is dispersed into new cells during mitosis.
The Human Genome Project is a collaborative effort of scientists around the world to map the entire gene sequence of organisms.
This information will be useful in
detection, prevention, and treatment of many genetic diseases.
DNA technologies allow scientists to identify, study, and modify genes.
Forensic identification is an
example of the application of DNA technology.
Gene therapy is a technique for correcting defective genes responsible for disease development.
Possible cures for: diabetes cardiovascular disease cystic fibrosis Alzheimer's Parkinson’s and many other diseases is possible.
The human manipulation of the genetic material of a cell.
Recombinant DNA- Genetically engineered DNA prepared by splicing genes from one species into the cells of a different species. Such DNA becomes part of the host's genetic makeup and is replicated.
Genetic engineering techniques are used in a variety of industries, in agriculture, in basic research, and in medicine.
There is great potential for the development of useful products through genetic engineering
EX., human growth hormone, insulin, and pest- and disease-resistant fruits and vegetables
We can now grow new body parts and soon donating blood will be a thing of the past, but will we go too far?