Thursday, November 8, 2007
Thurs-Day 1
Bio- we reviewed the process of transcription of DNA to mRNA and then we proceeded to the next natural step in getting the information that is contained in DNA to be expressed as a physical trait: that step involves the TRANSLATION of the information coded in the mRNA to the synthesis of a specific sequence and number of amino acids, which is forms a specific protein (enzyme, receptor protein, recognition protein, transport protein, microfilament, etc.).
We saw that TRANSLATION takes place on a ribosome outside of the nucleus (from where the mRNA traveled) and involves the connection of mRNA with TRANSFER RNA (tRNA). We calculated that the 20 possible amino acids that can be needed for a given protein can be coded for by mRNA IF the mRNA code is taken THREE base pairs at a time. Every three base pairs makes up a TRIPLET, which is called a CODON because the triplet "calls for or codes for" ONE particular amino acid. That particular amino acid is brought to the mRNA at the ribosome by a particular tRNA that has the matching/complementary ANTICODON for the mRNA codon.
It's easier to see this by example (as in the notes and handout from today):
If the DNA coding strand is GCATTC, then the mRNA strand formed from that via transcription is CGUAAG, which contains two codons. The mRNA is transported from the nucleus to the ribosomes where it "hooks up with/associates with" the complementary tRNA anticodons. In this case the two tRNA anticodons are GCA and UUC. Thus, two amino acids, arginine and lysine (according to the codon chart!), will be bonded together (a peptide bond) and will make up a small part of the whole protein (polypeptide) that is coded for by the DNA molecule/gene.
We then did an activity in which you practiced transcription and then translation of part of a DNA molecule/gene.
CHECK OUT the video of this on Blackboard.
Tomorrow, we will look for patterns and methods that will make this process easier to see.
Chem 7- took the Gas Laws test today. Will get those back to you, tomorrow.
Beware that the Quarterly Exam is upon us and will require copious review and study. Your quarterly exam grade, if it is higher than your lowest grade, will replace that lowest grade. So, there is hope especially when things end well! Know that the time that you put into studying this weekend can pay off both in terms of increasing and/or enhancing your chemistry knowledge and in terms of your grade for the first quarter. Use the quarterly review packet from class today as a starting point in your study.
We will do a lot of quarterly review, tomorrow. Come prepared with questions from all previous units.
Chem 8/9 - took the Gas Laws test today. Will get those back to you, tomorrow.
Some people had questions about the Charles's Law lab so we went over some of those today.
Beware that the Quarterly Exam is upon us and will require copious review and study. Your quarterly exam grade, if it is higher than your lowest grade, will replace that lowest grade. So, there is hope especially when things end well! Know that the time that you put into studying this weekend can pay off both in terms of increasing and/or enhancing your chemistry knowledge and in terms of your grade for the first quarter. Use the quarterly review packet from class today as a starting point in your study.
We will do as much quarterly review as possible, tomorrow. Come prepared with questions from all previous units.
We saw that TRANSLATION takes place on a ribosome outside of the nucleus (from where the mRNA traveled) and involves the connection of mRNA with TRANSFER RNA (tRNA). We calculated that the 20 possible amino acids that can be needed for a given protein can be coded for by mRNA IF the mRNA code is taken THREE base pairs at a time. Every three base pairs makes up a TRIPLET, which is called a CODON because the triplet "calls for or codes for" ONE particular amino acid. That particular amino acid is brought to the mRNA at the ribosome by a particular tRNA that has the matching/complementary ANTICODON for the mRNA codon.
It's easier to see this by example (as in the notes and handout from today):
If the DNA coding strand is GCATTC, then the mRNA strand formed from that via transcription is CGUAAG, which contains two codons. The mRNA is transported from the nucleus to the ribosomes where it "hooks up with/associates with" the complementary tRNA anticodons. In this case the two tRNA anticodons are GCA and UUC. Thus, two amino acids, arginine and lysine (according to the codon chart!), will be bonded together (a peptide bond) and will make up a small part of the whole protein (polypeptide) that is coded for by the DNA molecule/gene.
We then did an activity in which you practiced transcription and then translation of part of a DNA molecule/gene.
CHECK OUT the video of this on Blackboard.
Tomorrow, we will look for patterns and methods that will make this process easier to see.
Chem 7- took the Gas Laws test today. Will get those back to you, tomorrow.
Beware that the Quarterly Exam is upon us and will require copious review and study. Your quarterly exam grade, if it is higher than your lowest grade, will replace that lowest grade. So, there is hope especially when things end well! Know that the time that you put into studying this weekend can pay off both in terms of increasing and/or enhancing your chemistry knowledge and in terms of your grade for the first quarter. Use the quarterly review packet from class today as a starting point in your study.
We will do a lot of quarterly review, tomorrow. Come prepared with questions from all previous units.
Chem 8/9 - took the Gas Laws test today. Will get those back to you, tomorrow.
Some people had questions about the Charles's Law lab so we went over some of those today.
Beware that the Quarterly Exam is upon us and will require copious review and study. Your quarterly exam grade, if it is higher than your lowest grade, will replace that lowest grade. So, there is hope especially when things end well! Know that the time that you put into studying this weekend can pay off both in terms of increasing and/or enhancing your chemistry knowledge and in terms of your grade for the first quarter. Use the quarterly review packet from class today as a starting point in your study.
We will do as much quarterly review as possible, tomorrow. Come prepared with questions from all previous units.
# posted by C @ 1:57 PM 
