Principles of Biology By Frank H. Osborne, Ph. D. Molecular Genetics.

Slides:



Advertisements
Similar presentations
DNA.
Advertisements

Nucleic Acids and Protein Synthesis
• Exam II Tuesday 5/10 – Bring a scantron with you!
DNA, RNA, & Protein Synthesis Mrs. Morgan Biology.
Nucleic Acids DNA vs. RNA
Chapter # Discovery of DNA 10.2 DNA Structure
12-3: RNA AND PROTEIN SYNTHESIS Biology 2. DNA double helix structure explains how DNA can be copied, but not how genes work GENES: sequence of DNA that.
Chapter 10 – DNA, RNA, and Protein Synthesis
DNA & Genetics Biology. Remember chromosomes? What are genes? Made up of DNA and are units of heredity; unique to everyone What are traits? Are physical.
CHAPTER 12 DNA & RNA. Griffith & Transformation Discovered transformation using bacteria that causes pneumonia Transformation  Process in which part.
What is the structure of DNA? Hw Q 1-4 p. 299.
NUCLEIC ACIDS AND PROTEIN SYNTHESIS. QUESTION 1 DNA.
Protein Synthesis. The DNA Code It is a universal code. The order of bases along the DNA strand codes for the order in which amino acids are chemically.
DNA / RNA Notes. l. DNA Structure A. Chromosomes are made up of DNA, or deoxyribonucleic acid. DNA is the master copy, or blueprint, of an organism’s.
Mrs. Degl Molecular Genetics DNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms. Nearly every cell in a.
RNA & Protein Synthesis.
The Central Dogma of Molecular Biology DNA → RNA → Proteins Biology II D. Mitchell.
CHAPTER 12 STUDY GUIDE MATER LAKES ACADEMY MR. R. VAZQUEZ BIOLOGY
DNA Deoxyribose Nucleic Acid – is the information code to make an organism and controls the activities of the cell. –Mitosis copies this code so that all.
RNA and Protein Synthesis
12-3 RNA and Protein Synthesis
DNA The Code of Life.
RNA. What is RNA?  RNA stands for Ribonucleic acid  Made up of ribose  Nitrogenous bases  And a phosphate group  The code used for making proteins.
Chapter 13 –RNA and Protein Synthesis
Protein Synthesis Review By PresenterMedia.com PresenterMedia.com.
RNA & Protein Synthesis
Double Helix DNA consists of two strips, made of sugars and phosphates, twisted around each other and connected by nitrogen bases. Looks like a spiral.
PROTEIN SYNTHESIS Review. Cell organelle where ______________ proteins are made Copying DNA _________________ G roup of 3 nucleotides _____________ in.
DNA Deoxyribose Nucleic Acid – is the information code to make an organism and controls the activities of the cell. –Mitosis copies this code so that all.
Do you know what this is?. DNA Stands for Deoxyribose Nucleic Acid It is a long molecule called a polymer Shape: double helix.
CHAPTER 10 DNA REPLICATION & PROTEIN SYNTHESIS. DNA and RNA are polymers of nucleotides – The monomer unit of DNA and RNA is the nucleotide, containing.
RNA and Protein Synthesis Chapter How are proteins made? In molecular terms, genes are coded DNA instructions that control the production of.
DNA Deoxyribose Nucleic Acid – is the information code to make an organism and controls the activities of the cell. –Mitosis copies this code so that all.
Molecular Genetics Molecular Genetics. Question??????? What IS a gene or trait? In the case above, what are freckles? What IS a gene or trait? In the.
Protein Synthesis DNA to RNA to Proteins. DNA: Deoxyribonucleic Acid Video – – DNA carries genetic.
12-3 RNA and Protein Synthesis Page 300. A. Introduction 1. Chromosomes are a threadlike structure of nucleic acids and protein found in the nucleus of.
DNA, RNA & Protein Synthesis. A. DNA and the Genetic Code 1. DNA controls the production of proteins by the order of the nucleotides.
RNA and Transcription. Genes Genes are coded DNA instructions that control the production of proteins within the cell To decode the genetic message, you.
8.2 KEY CONCEPT DNA structure is the same in all organisms.
Transcription and Translation
Nucleic Acids Include DNA and RNA Function to carry coded information The code controls the sequence of amino acids in a polypeptide i.e. the primary structure.
Genetics: RNA and Protein Synthesis
Notes: Transcription DNA vs. RNA
Chapter 10 – DNA, RNA, and Protein Synthesis
DNA Structrue & Function
RNA Ribonucleic Acid Single-stranded
Protein Synthesis.
Protein Synthesis.
12-3 RNA and Protein Synthesis
Protein Synthesis.
The Double Helix.
RNA Another Nucleic Acid.
Why do we use mice to conduct medical experiments?
Nucleic Acids and Protein Synthesis
DNA and Genes Chapter 11.
DNA Replication and Protein Synthesis
RNA and Transcription DNA RNA PROTEIN.
DNA RNA Protein Synthesis Review
RNA is a nucleic acid made of linked nucleotides.
PROTEIN SYNTHESIS Chapter 10
Molecular Basis of Heredity
DNA and Genes Chapter 13.
DNA, RNA & PROTEINS The molecules of life.
RNA is a nucleic acid made of linked nucleotides.
Genes and Protein Synthesis Review
Nucleic Acids And Protein Synthesis
DNA, RNA, and Protein Synthesis
Unit 3: Genetics Part 1: Genetic Informaiton
DNA Deoxyribonucleic Acid.
Presentation transcript:

Principles of Biology By Frank H. Osborne, Ph. D. Molecular Genetics

Introduction The topic of Molecular Genetics deals with the DNA of the cell and the process that is used to decode its genetic code and use the information to make proteins. So, DNA contains the hereditary information that is passed from one generation to the next in humans. The expression of DNA is protein.

Introduction The term given for making a protein is called "protein synthesis." This requires DNA to provide the coded genetic information, the three types of RNA, and the amino acids that are the components of the protein. Protein synthesis is similar to making a car. The car is made of different parts brought together on the assembly line.

Deoxyribonucleic Acid is DNA DNA is a long polymer consisting of phosphate groups alternating with sugars. Nucleotides are the subunits of nucleic acids. A nucleotide consists of a base, a sugar and a phosphate.

Deoxyribonucleic Acid is DNA The sugar in DNA is called deoxyribose. Each sugar has a base attached to it. The bases are made of carbon and nitrogen and are called nitrogenous bases. There are two kinds of nitrogenous bases called purine bases and pyrimidine bases. The purine bases found in DNA are adenine (A) and guanine (G). The pyrimidine bases found in DNA are cytosine (C) and thymine (T).

Ribonucleic Acid is RNA RNA is a long polymer consisting of phosphate groups alternating with sugars. The sugar in RNA is called ribose. Each sugar has a base attached to it. The purine bases found in RNA are adenine (A) and guanine (G). The pyrimidine bases found in RNA are cytosine (C) and uracil (U). Both molecules are similar. DNA has deoxyribose and thymine, RNA has ribose and uracil.

Structure of DNA DNA has two strands, each with sugars alternating with phosphates, and with a base attached to each sugar. The bases pair between the DNA strands. Adenine always pairs with Thymine. If there is an Adenine on the first strand, there will be a Thymine opposite it. Also, a Thymine on the first strand will be matched by an Adenine on the other.

Structure of DNA Similarly, Guanine pairs with Cytosine. A Guanine on the first strand will be paired with a Cytosine on the other strand. Also, a Cytosine on the first strand will be paired with a Guanine on the other. The base pairs of DNA are held together by weak attractions known as hydrogen bonds.

Structure of DNA

Replication of DNA The two DNA strands unzip at the hydrogen bonds and each acts as a template. The template is a pattern that will be replicated by enzymes synthesizing the new DNA strands. After the DNA strands are unzipped, the enzyme DNA-dependent DNA polymerase comes and makes a new strand matching each base with its correct partner.

Replication of DNA Wherever the template strand has an A, the new strand will receive a T; and wherever there is T, the new strand will receive an A. Similarly, wherever the template strand has a G, the new strand will receive a C; and wherever there is a C, the new strand will receive a G. As a result, the new strand will be an exact copy of the original strand. The process is called semiconservative replication.

Gene Expression Protein Synthesis The DNA causes a protein to be made as a result of a series of steps. These steps are known as transcription and translation.

Transcription The DNA template is used to make messenger RNA (mRNA). The mRNA is the transcribed copy of the DNA molecule so it contains the genetic message encoded in the DNA. The mRNA travels to the endoplasmic reticulum where ribosomes attach to it. The ribosomes decode the coded genetic message and translate it to make a protein molecule. The code that the mRNA contains was broken in the 1960s.

Transcription The genetic code is read from the mRNA molecule in units of three bases known as codons. In order to use the DNA code, look up the first base, then the second base, then the third base. For example if the codon is UUU, the amino acid is phe (phenylalanine).

Translation Translation of the coded message involves the ribosomes. Ribosomes are structures made of ribosomal RNA (rRNA) and protein molecules. Each ribosome contains two components. The large component serves as the workspace where the protein is synthesized while the small component serves as the mechanism hat helps to join the amino acids together.

Translation Bringing the amino acids of the protein to the ribosome is the job of transfer RNA (tRNA). Each tRNA molecule carries a specific amino acid. The system knows which one to use because the tRNA molecule has a specific anticodon that exactly matches the codon of the mRNA. So, if the mRNA codon was UUU, the anticodon would be AAA. Adenine and Uracil are complementary, so they would match exactly.

Translation As its tRNA brings each amino acid to the ribosome, the chain of amino acids grows in length by one amino acid. Enzymes on the ribosome remove the incoming amino acid from its tRNA and add it to the growing polypeptide chain using a condensation reaction.

Mutations Mutations are changes in genes. They can be transmitted to the offspring. A point mutation results from the change in a single base in the DNA molecule. An example of a disease resulting from a point mutation is sickle-cell anemia. The hemoglobin molecule in sickle-cell patients differs in structure at only one place from the normal hemoglobin molecule.

Mutations Frame-shift mutation The code of the bases in DNA is translated to RNA. Transfer RNA decodes the mRNA molecule in groups of three. Each group of three is a reading frame. Deletions of bases, duplications of bases, or other abnormalities can result in an alteration of the reading frame. Such an alteration is called a frame-shift mutation.

Mutations Frame-shift mutation Frame-shift mutations cause changes in the structures of proteins so that they will not function correctly.

Problem 15 Revealed The Sequence of DNA - A A A G A T T A C C A T G G G C C G G C T -

Problem 15 Revealed (a) Sequence of mRNA - A A A G A T T A C C A T G G G C C G G C T - - U U U C U A A U G G U A C C C G G C C G A -

Problem 15 Revealed (b) Sequence of Amino Acids - A A A G A T T A C C A T G G G C C G G C T - - U U U C U A A U G G U A C C C G G C C G A - - phe - leu - met - val - pro - gly - arg -

Problem 15 Revealed (c) Misread transcription T - A A A G A T T A C C A T G G G C C G G C T - A - U U U C U A A U G G U A C C C G G C C G A - - phe - leu - met - val - pro - gly - arg - his

Problem 15 Revealed (d) Frameshift mutation - A A A G A T T A C C A T G G G C C G G C T - - U U U C U A A U G G U A C C C G G C C G A - - phe - leu - met - val - pro - gly - arg - - ser - asn - gly - thr - gly - arg -

The End Principles of Biology Molecular Genetics