1. Objectives a. Summarize the relationship between genes & DNA, the events of DNA replication, and the events of protein synthesis. b. Describe and model the structure of the DNA and RNA molecules and the general structure of a protein. c. Summarize the events of DNA replication, transcription, and translation. d. Differentiate between DNA and RNA in terms of structure & function. e. Distinguish between the three types of RNA. f. Differentiate between types of mutations. g. Identify mutations in a string of DNA or RNA and describe the consequences of that mutation when forming proteins. 2. Key Vocabulary (20) nucleotide
base pairing
chromatin
histone
replication
DNA polymerase
messenger RNA
ribosomal RNA
transfer RNA
transcription
RNA polymerase
intron
exon
codon
translation
anticodon
mutation
point mutation
frameshift mutation
hox gene
3. Essential Questions a. How does DNA copy itself? b. How are proteins formed? c. What are mutations, how are they caused, and what are the consequences of mutated DNA? 4. Assessments & Schedule
*Miss Taylor reserves the right to change as needed*
DNA aka __________________________ is made of ______________ wrapped around proteins called ________________ which allow DNA to coil in the nucleus. - __________________________________ first discovered the structure of DNA. - DNA looks like a _________-________ or twisted ladder under a microscope. - DNA is _____________ - _______________ and found in the ________________. - Contains ______________ information and instructions for making ___________ which control cell activities. - Made of monomers called ______________ (monomers of nucleic acids). Draw a model of DNA:
Function -
DNA copies itself through ________________ (_______-_________________). ___________________________ is the protein that moves along the DNA strand during replication that ensures the code copies correctly. DNA is made of 4 ____________________ bases. These bases pair together to create a code. 1. ______________ include ___________(__) and _____________(___). These have a ___________-____________ structure. 2. ______________ include____________ (___) and __________ (___). These have a ___________-____________ structure. When DNA replicates (copies), adenine (A) pairs with _____________(___) and cytosine (C) pairs with _____________(___).
For example: Original: Complementary:
A A C T G G T A C T T A
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RNA & Protein Synthesis Structure ●
RNA aka ____________________ is found in the _____________ and makes ______________. ● RNA is ______________-stranded. ● RNA contains the base ________________(___) instead of ____________(___). ● In RNA _______=_______, ________=_________, ________=_________ and ________=_________. (The RNA strand CANNOT contain any “T”s.) Types ●
__________ or messenger RNA, enters the nucleus and copies the part of DNA needed, then carries that copy to the ribosome. a. _______________ - part of DNA code that DOES NOT code for protein b. _______________ - part of DNA code that DOES code for protein c. _______________ - protein that “reads” the code so mRNA can match bases and make a copy
●
__________ or transfer RNA, takes the code from mRNA and translates it into a strand of amino acids to form a polypeptide (string of amino acids) that make a protein. There are 20 possible amino acids! a. _______________ - 3-letter “word” that codes for an amino acid – found in mRNA strand b. _______________ - matching 3-letter “word” assembled by tRNA to complete the protein
●
__________ or ribosomal RNA, makes up ribosomes
Function ●
__________________ - mRNA copies the code it needs from DNA and takes it to the ribosome (transcribe = copy) ● __________________ - tRNA takes the code from mRNA by turning it into codons, reading them, and assembling the correct amino acids into a chain – Completes the protein by matching anticodons to codons in mRNA. (translate=make something new) **Amino Acid Wheel**
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For example: Original DNA: mRNA: anticodons: Amino Acid Sequence: Original DNA: mRNA: anticodons: Amino Acid Sequence: Original DNA: mRNA: anticodons: Amino Acid Sequence:
What happens if you get a “Stop” codon?__________________________ Amino Acid Wheel
Helpful Hints 1. Work from the inside to the outside. 2. Make sure you read the codon NOT the anti-codon. 3. If you see a "T" in your codon, go back and check your mRNA strand.
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Mutations Gene Mutations _________________________ - caused by a ________________ of one base for another affects only one amino acid Ex.
*Health effects: ________________________ - caused by an ________________ or _______________ “shifts” the way the code is read and affects multiple codons Ex.
*Health effects: Chromosomal Mutations ________________________ - Gene(s) are repeated Ex.
*Health effects: ________________________ - Gene(s) are omitted Ex.
*Health effects: _________________________ - Genes are mixed up Ex.
* Health effects: _________________________ - Gene(s) break off from one part of a chromosome and attach to another Ex.