Protein Synthesis: From Gene RNA Protein Trait

Transcription

1 Protein Synthesis: From Gene RNA Protein Trait

2 Human Genome The human genome contains about genes. Each gene is a of DNA (sequence of nitrogen bases) contained within each chromosome. Each chromosome contains hundreds to thousands of. Each of these genes provide instructions for making a specific (like ).

3 Proteins The proteins produced by cells influence each of your and guide. What are proteins made of? How many amino acids are there? But there s only 4 bases in DNA? Sequences of (in groups of ) code for each. The group of the bases are called.

4 4 bases/20 amino acids Codons a set of that code for a particular. Also, there are and codons sets of 3 bases that indicate where the code for a particular protein ( ) starts and where it stops.

5 RNA Codons

6 Transcription From DNA to RNA Proteins are synthesized at the, so how does that information get from the DNA in the nucleus to the? - is our answer. It copies the sequence of the gene and leaves the nucleus to travel to one of the. RNA Ribosome

7 RNA (Ribonucleic Acid) vs. DNA Contains (instead of Thymine in DNA) (instead of 2 strands) sugar(instead of Deoxyribose) of nucleus (instead of only inside) types (instead of one type) Codons and (instead of just codons)

8 Making mrna by Transcription This is a similar process to but instead of making new DNA strands, a single strand is made from a. It is called because the mrna is making a of the instructions for making protein like a scribe records a. mrna is RNA and takes the genetic information out of the nucleus and to the ribosome. rrna is RNA and makes up the ribosomes. The 3 rd kind of RNA will come later.

9 Making mrna by Transcription-Steps 1. RNA enzyme attaches to DNA where the beginning of the is located ( codon: TAC). 2. Free floating (ribonucleotides) match their bases with the sequence of bases on the gene (located on only side of the DNA) with the help of RNA polymerase. RNA to DNA base pairing: with A, with T, with C 3. RNA polymerase attaches the nucleotides together as it runs along the gene. Covalent bonds form between the and to create a single stranded mrna molecule. 4. When a is reached, the RNA polymerase and the mrna strand.

10 Translation- From mrna to Protein mrna moves to a. trna ( RNA) brings to the ribosomes How does the trna know which are the correct amino acids? trna has that match up with the mrna s. It is the sequence of that determines which protein has been synthesized.

11 Translation From mrna to Protein It is called since nucleic acids are being into amino acids like one language to another. A new RNA called RNA (trna) is used. The trna is folded exposing a part that compliments an mrna codon called an. One end carries a specific. The amino acid it carries is based on the sequence.

12 Transcription Translation Protein Synthesis- Transcription & Translation

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14 Review of Concepts 1. What is the name of the process of a gene being copied by creating an mrna strand? 2. Indicate the difference between DNA and mrna: Difference DNA RNA Sugar Bases # of strands 3. What is the name of the enzyme used to perform transcription?

15 Review of Concepts 1. For the sequence of DNA bases below, write what the mrna bases sequence would be. DNA: mrna: T A C G C C T A T A G T A C T 2. What is the name of the process that happens at the ribosome? 3. Define a codon:

16 Review of Concepts Label the picture below with the following terms: Ribosome, trna, mrna, anti-codon

17 Mutations! Mutation is a change in the DNA Three types: 1.Point Mutation This is a change in a single base pair in DNA 2.Frame Shift Mutation This is a deletion or addition of a single base in DNA 3.Chromosome Mutation Sometimes parts of chromosomes break off and get lost during meiosis or mitosis.

18 Point Mutation

19 Mutations! Mutation is a in the. Three types: 1. Mutation This is a change in a in DNA. 2. Mutation This is a or of a single base in DNA. 3. Mutation Sometimes parts of break off and get lost during or.

20 Point Mutation

21 Point Mutation Changes in a single Can cause a change in one When does a point mutation not cause problems? When does a point mutation cause major problems?

22 Example of a Frameshift mutation

23 Frameshift Mutation Often causes more problems than a point mutation. Why?

24 Chromosome Mutation

25 Chromosomal Cont. Extra Chromosome Example: Trisomy 21- Missing Chromosome -Example: - Turner Syndrome