DNA Protein Synthesis SOL BIO 6 f i

DNA & Protein Synthesis SOL: BIO 6 f - i

SOL: BIO 6 f - i • The student will investigate and understand common mechanisms of inheritance and protein synthesis. • Key concepts include: – f) the structure, function, and replication of nucleic acids (DNA and RNA); and – g) events involved in the construction of proteins.

SOL: BIO 6 f - i • • The student will investigate and understand common mechanisms of inheritance and protein synthesis. Key concepts include: – h) use, limitations, and misuse of genetic information; and – i) exploration of the impact of DNA technologies.

History • Before the 1940’s scientists didn’t know what material caused inheritance. • They suspected it was either DNA or proteins.

History • A series of experiments proved that DNA was the genetic material responsible for inheritance.

History • In 1952, Alfred Hershey and Martha Chase did an experiment using a virus that infects E. coli bacteria. • The experiment proved that DNA and not protein is the factor that influences inheritance.

History • Erwin Chargaff discovered the base pairing rules and ratios for different species. • Adenine pairs with Thymine • Cytosine pairs with Guanine.

History • Rosalind Franklin & Maurice Wilkins had taken the 1 st pictures of DNA using X-ray crystallization

This proved that DNA had a helical shape.

History • The Nobel Prize in Medicine 1962 Francis Harry Compton Crick James Dewey Watson Rosalind Franklin (Died of cancer 1958) Maurice Hugh Frederick Wilkins

Watson Crick Wilkins has become a historical footnote and Watson & Crick are remembered as the Fathers of DNA

DNA Phosphate Group O O=P-O O Nitrogenous base (A, T, G, C) 5 CH 2 O C 4 Sugar C 1 (deoxyribose) C 3 C 2 N

Nitrogen Bases • 2 types of Nitrogen Bases – Purines • Double ring –G & A – Pyrimidines • Single ring –C & U & T PGA CUT PY

DNA - double helix 5 T O A 3 P 5 O C G 1 4 5 3 2 1 5 O O T 3 A O 3 P 4 2 3 P P 3 5 P P

DNA • The genetic code is a sequence of DNA nucleotides in the nucleus of cells.

DNA • DNA is a doublestranded molecule. • The strands are connected by complementary nucleotide pairs (A-T & C-G) like rungs on a ladder. • The ladder twists to form a double helix.

DNA • During S stage in interphase, DNA replicates itself. • DNA replication is a semiconservative process.

DNA • Semi-conservative means that you conserve part of the original structure in the new one. • You end up with 2 identical strands of DNA.

Good Morning! 1. Please complete the half sheet on the front desk. Please write this in your agenda: TEST on 3/22 (Wednesday). What do I need to study? • • • DNA Structure DNA Replication Protein Synthesis (Transcription/Translation) Mutations (today) DNA Technologies (next class) Today: 1. 2. 3. Mutation Notes Practice and videos Prepare for test on the 22 nd!

DNA • Gene - a segment of DNA that codes for a protein, which in turn codes for a trait (skin tone, eye color, etc. )

DNA • A mistake in DNA replication is called a mutation. • Many enzymes are involved in finding and repairing mistakes.

Mutations • What causes mutations? – Can occur spontaneously – Can be caused by a mutagen • Mutagen: An agent, such as a chemical, ultraviolet light, or a radioactive element, that can induce or increase the frequency of mutation in an organism.

Mutations • Some mutations can: • Have little to no effect • Be beneficial (produce organisms that are better suited to their environments) • Be deleterious (harmful)

Mutations Types of mutations Point Mutations or Substitutions: causes the replacement of a single base nucleotide with another nucleotide • Missense- code for a different amino acid • Nonsense- code for a stop, which can shorten the protein • Silent- code for the same amino acid (AA)

Mutations • Example: Sickle Cell Anemia

Mutations • Frame Shift Mutations: the number of nucleotides inserted or deleted is not a multiple of three, so that every codon beyond the point of insertion or deletion is read incorrectly during translation • Ex. : Crohn’s disease

Deletion

Mutations • Chromosomal Inversions: an entire section of DNA is reversed. – Ex. : hemophilia, a bleeding disorder

DNA Repair • A complex system of enzymes, active in the G 2 stage of interphase, serves as a back up to repair damaged DNA before it is dispersed into new cells during mitosis.

Good Afternoon! Warm Up: Copy these facts. **Keep up with all of them for the test. • Protein makes up about 20% of the human body; second only to water. • The human body contains more than 100, 000 different proteins. • The structure of certain proteins can trigger allergic reactions in the body. This is why some people are allergic to gluten, a protein found mainly in breads and cereal. Today: 1. 2. Protein Synthesis Notes and videos Class work and Practice

RNA Phosphate Group O O=P-O O Nitrogenous base (A, U , G, C ) 5 CH 2 O Sugar (ribose) C 4 C 3 C 2 N C 1

RNA • Function: obtain information from DNA & synthesizes proteins

3 differences from DNA 1. Single strand instead of double strand 2. Ribose instead of deoxyribose 3. Uracil instead of thymine

3 types of RNA 1. Messenger RNA (m. RNA)- copies information from DNA for protein synthesis Codon- 3 base pairs that code for a single amino acid. codon

3 types of RNA 2. Transfer RNA (t. RNA)- collects amino acids for protein synthesis Anticodon-a sequence of 3 bases that are complementary base pairs to a codon in the m. RNA

3 types of RNA 3. Ribosomal RNA (r. RNA)- combines with proteins to form ribosomes

Amino Acids • Amino acids- the building blocks of protein • At least one kind of t. RNA is present for each of the 20 amino acids used in protein synthesis.

Transcription - m. RNA is made from DNA & goes to the ribosome Translation - Proteins are made from the message on the m. RNA

Transcription • In order for cells to make proteins, the DNA code must be transcribed (copied) to m. RNA. • The m. RNA carries the code from the nucleus to the ribosomes.

Translation • At the ribosome, amino acids (AA) are linked together to form specific proteins. • The amino acid sequence is directed by the m. RNA molecule. Amino acids ribosome

Make A Protein • DNA sequence ATG AAA AAC AAG GTA TAG • m. RNA sequence UAC UUU UUG UUC CAU AUC

Make m. RNA • m. RNA sequence UAC UUU UUG UUC CAU AUC • t. RNA sequence AUG AAA AAC AAG GUA UAG

Make m. RNA • m. RNA sequence UAC UUU UUG UUC CAU AUC • t. RNA sequence AUG AAA AAC AAG GUA UAG • Amino Acid sequence Tyr Phe Leu Phe His Ile

Possible Proteins for #4 Amino Acid Sequence Meth-Glut-Ser-Ala-Isoleu Meth-Glut-Asp-Leu-Threo-Arg. Ala-Leu Protein Name Collagen Tubulin Function Elasticity of the skin Makes up the microtubules (cytoskeleton) of the cell. Meth-Asp-Pro-Stop-Leu-Tyr-Ala. Phenyl Actin Meth-Asp. Acid-Ser-Pro-Asp Hemoglobin Carries oxygen on the red blood cells Meth-Leu-Pro-Glut-Leu-Tyr-Ala. Threo-Meth-Tyr Fibronectin Extracellular matrix that holds cells together to make tissues. Cyclase Controls the cell cycle and timing of Interphase and Mitosis Meth-Asp-Pro-Ser-Leu-Lys Protein found in muscle along with myosin.

Human Genome Project • 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.

Example of a DNA Sequence: What could you do with this? • Transcribe, translate study the composition of the proteins coded for in this sequence • Compare to other human sequences at this position on this chromosome to look for mutations. • Compare to the DNA of other organisms.

DNA Technologies • DNA technologies allow scientists to identify, study, and modify genes. • Forensic identification is an example of the application of DNA technology.

Gene Therapy • 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.

Genetic Engineering • 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 • Genetic engineering techniques are used in a variety of industries, in agriculture, in basic research, and in medicine. This genetically engineered cow resists infections of the udders and can help to increase dairy production.

Genetic Engineering • There is great potential for the development of useful products through genetic engineering • EX. , human growth hormone, insulin, and pestand disease-resistant fruits and vegetables Seedless watermelons are genetically engineered

Genetic Engineering • We can now grow new body parts and soon donating blood will be a thing of the past, but will we go too far? Photo of a mouse growing a "human ear"

Good Afternoon! Welcome Back! 1. Warm Up- DNA Review Sheet Looking Ahead: • This week: finish DNA/RNA/Protein Synthesis • Next 3 weeks: o Evolution o Kingdoms of Life o Ecology o SOL Review (think Advanced Score!)