FROM DNA TO YOU Worksheet Notes

PART ONE: DNA DNA: deoxyribonucleic acid DNA: deoxyribonucleic acid Deoxyribose= sugar Deoxyribose= sugar DNA is made of smaller molecules called nucleotides. (Sugar + phosphate + base) DNA is made of smaller molecules called nucleotides. (Sugar + phosphate + base) The center “rungs” hold the four bases: The center “rungs” hold the four bases: Adenine = Thymine Adenine = Thymine Guanine = Cytosine Guanine = Cytosine

PAIRING PRACTICE A section of DNA has the following sequence: A section of DNA has the following sequence: CGATTTCCTACCGGA CGATTTCCTACCGGA What is the sequence of its corresponding strand? What is the sequence of its corresponding strand? GCTAAAGGATGGCCT GCTAAAGGATGGCCT

PART TWO: RNA RNA = ribonucleic acid RNA = ribonucleic acid Like DNA, RNA contains four bases: Like DNA, RNA contains four bases: Adenine = Uracil Adenine = Uracil Guanine = Cytosine Guanine = Cytosine RNA is single-stranded (which makes it smaller), can leave the nucleus, and the sugar in its backbone is ribose. RNA is single-stranded (which makes it smaller), can leave the nucleus, and the sugar in its backbone is ribose.

RNA, continued RNA is a copy of DNA that can leave the nucleus of the cell and be used to build proteins. RNA is a copy of DNA that can leave the nucleus of the cell and be used to build proteins. The RNA used in transcription, or the copying process, is called mRNA. The “m” stands for messenger! The RNA used in transcription, or the copying process, is called mRNA. The “m” stands for messenger! The RNA used in translation, or the building process, is called tRNA. The “t” stands for transfer! (We’ll learn more about this today; aren’t you thrilled? :D) The RNA used in translation, or the building process, is called tRNA. The “t” stands for transfer! (We’ll learn more about this today; aren’t you thrilled? :D)

TRANSCRIPTION PRACTICE A section of DNA (or gene) has the following sequence: A section of DNA (or gene) has the following sequence: CGATTTCCTACCGGA CGATTTCCTACCGGA What is the sequence of the mRNA molecule that matches up with it? What is the sequence of the mRNA molecule that matches up with it? GCUAAAGGAUGGCCU GCUAAAGGAUGGCCU

TRANSLATION Translation= using mRNA to select the amino acids to build a protein Translation= using mRNA to select the amino acids to build a protein Amino acids= the building blocks of a protein Amino acids= the building blocks of a protein Three bases in a strand of mRNA (a triplet) codes for a single amino acid. Three bases in a strand of mRNA (a triplet) codes for a single amino acid. Each triplet is called a codon. Each triplet is called a codon.

COUNT THE TRIPLETS How many amino acids will be coded for by this gene? How many amino acids will be coded for by this gene? GCUAAAGGAUGGCCA GCUAAAGGAUGGCCA GCU|AAA|GGA|UGG|CCU GCU|AAA|GGA|UGG|CCU 5! 5!

Which amino acids? Codon 1: GCU Codon 1: GCU Alanine Alanine Codon 2: AAA Codon 2: AAA Lysine Lysine Codon 3: GGA Codon 3: GGA Glycine Glycine Codon 4: UGG Codon 4: UGG Tryptophan Tryptophan Codon 5: CCU Codon 5: CCU Proline Proline

Congrats, you just translated an mRNA strand! continuing on…

ERRORS IN TRANSCRIPTION Changing a single base pair in a DNA strand (through damage or copy errors) can affect the amino acids it codes for, which in turn affects the proteins built. Changing a single base pair in a DNA strand (through damage or copy errors) can affect the amino acids it codes for, which in turn affects the proteins built. This is how mutations occur. This is how mutations occur. Some are fatal. Some are beneficial. Yay chaos. Some are fatal. Some are beneficial. Yay chaos.

TO REVIEW: The process of mRNA being produced from a section of DNA is called ________. The process of mRNA being produced from a section of DNA is called ________. Transcription Transcription The process where a protein is made based on the information carried in a segment of mRNA is called _______. The process where a protein is made based on the information carried in a segment of mRNA is called _______. Translation Translation

HOMEWORK Worksheet Question #11 is due Wednesday. Worksheet Question #11 is due Wednesday. Worksheet Question #11 is due Wednesday. Worksheet Question #11 is due Wednesday.