Tuesday, November 13, 2007
Tues-Day 1
Bio- we practiced transcription and translation. We then began to discuss genetic mutations and mutagens (agents that cause mutations such as x-rays, chemical carcinogens, etc.). We then took a gene on a DNA molecule and saw how a point mutation caused the transcription of a different mRNA molecule (base sequence). HOWEVER, even though the mRNA molecule was slightly different, it STILL coded for the same protein, in this case. That happens sometimes and is caused by the fact that SEVERAL DIFFERENT mRNA codons can code for the SAME amino acid. You saw that on your mRNA codon chart during the activity today.
Tomorrow, we will look at the mutation that causes the disease "sickle cell anemia".
You will see that a SINGLE point mutation in the gene that codes for the oxygen-carrying pigment/protein, hemoglobin, causes the amino acid sequence to alter by ONE amino acid, which is enough to give the protein a VERY different shape, which causes the red blood cells to have a "sickle" shape.
So, as you will see, mutations can cause DNA to code for drastically different, harmful, fatal, or nonfunctional proteins!
CHEM Classes 7/8/9: we had our Quarterly Part II today. Part I multiple-choice section of the Quarterly exam is tomorrow.
Take HEED of this: I am grading the exam and students who are not identifying what each question is asking are losing points AND wasting time on the test answering questions that are not there. Please stop doing this to yourselves.
For example, when a question directs you to use a reference table and you do not use said table, you cannot get the question right.
Those who are employing the care of using the test-taking skills of highlighting/underlining/circling ONLY the key terms and data, drawing out and LABELING their pictures, and using the reference tables are avoiding careless errors and are doing very well.
Focus on the various multiple-choice sections and multiple-choice review packets for your last minute practice, tonight.
Tomorrow, we will look at the mutation that causes the disease "sickle cell anemia".
You will see that a SINGLE point mutation in the gene that codes for the oxygen-carrying pigment/protein, hemoglobin, causes the amino acid sequence to alter by ONE amino acid, which is enough to give the protein a VERY different shape, which causes the red blood cells to have a "sickle" shape.
So, as you will see, mutations can cause DNA to code for drastically different, harmful, fatal, or nonfunctional proteins!
CHEM Classes 7/8/9: we had our Quarterly Part II today. Part I multiple-choice section of the Quarterly exam is tomorrow.
Take HEED of this: I am grading the exam and students who are not identifying what each question is asking are losing points AND wasting time on the test answering questions that are not there. Please stop doing this to yourselves.
For example, when a question directs you to use a reference table and you do not use said table, you cannot get the question right.
Those who are employing the care of using the test-taking skills of highlighting/underlining/circling ONLY the key terms and data, drawing out and LABELING their pictures, and using the reference tables are avoiding careless errors and are doing very well.
Focus on the various multiple-choice sections and multiple-choice review packets for your last minute practice, tonight.
# posted by C @ 2:41 PM 
