Genetic Mutations What mistakes can occur when DNA is replicated?

Why? The genes encoded in your DNA result in the production of proteins that perform specific functions within your cells. Various environmental factors and spontaneous events can lead to changes in genes. These changes, called mutations, can lead to alterations in the structure and activity of the proteins your cells use in their daily activities. In other words, changes to your genotype can result in changes to your phenotype. We all have mutations in most of our body cells—yet we are, for the most part, normal and functional human beings. How can that be?

Model 1 – Gene Mutations Sequence 1 (normal) DNA sequence

… T A C G T A G T C A C C T A A T G G A T C…

mRNA sequence A U G C A U C A G U G G A U U A C C U A G Amino acid sequence Met His Gln Trp Ile Thr stop Sequence 2 (substitution) DNA sequence

… T A C G T A G T C A G C T A A T G G A T C…

mRNA sequence A U G C A U C A G U C G A U U A C C U A G Amino acid sequence Met

His

Gln

Ser

Ile

Thr

stop

Sequence 3 (insertion) DNA sequence

… T A C G T A T G T C A C C T A A T G G A T C…

mRNA sequence A U G C A U A C A G U G G A U U A C C U A G… Amino acid sequence Met His Thr Val Asp Tyr Leu... Sequence 4 (deletion) DNA sequence

… T A C G T A G T C C C T A A T G G A T C…

mRNA sequence A U G C A U C A G G G A U U A C C U A G… Amino acid sequence Met His Gln Gly Leu Pro…   1. How many nucleotides are present in the “normal” DNA sequence in Model 1?   2. How many codons are contained in the mRNA that is produced by the “normal” DNA in Model 1?   3. How many amino acids will be in the polypeptide produced by the normal DNA/mRNA sequence? Genetic Mutations

1

  4. What is the amino acid sequence of the polypeptide produced by the “normal” DNA sequence in Model 1?   5. Consider DNA sequence 2 in Model 1. The mutation in that sequence is a substitution mutation. a. Compare sequence 2 with sequence 1 and describe the mutation that has occurred. b. What is the effect of this substitution mutation on the amino acid sequence?   6. Consider DNA sequence 3 in Model 1. The mutation in that sequence is an insertion mutation. a. Compare sequence 3 with sequence 1 and describe the mutation that has occurred. b. What is the effect of the insertion mutation on the amino acid sequence as compared to the “normal” amino acid sequence in Model 1?

  7. Consider DNA sequence 4 in Model 1. The mutation in that sequence is a deletion mutation. a. Compare sequence 4 with sequence 1 and describe the mutation that has occurred. b. What is the effect of the deletion mutation on the amino acid sequence as it is compared to the “normal” amino acid sequence in Model 1?   8. In your group, use grammatically correct sentences to define each of the following mutations.

Substitution mutation—



Insertion mutation—



Deletion mutation—

2 POGIL™ Activities for AP* Biology

  9. Considering your knowledge of codons and how they code for an amino acid, would all substitution mutations lead to a change in the amino acid sequence? Explain your reasoning.

10. Would all insertion or deletion mutations lead to a change in the amino acid sequence? Explain your reasoning.

11. What could potentially cause more damage (or a greater benefit) to an organism, a substitution mutation or an insertion mutation? Explain your reasoning.

12. What could potentially cause more damage (or a greater benefit) to an organism, a deletion mutation at the beginning of a DNA sequence or at the end of a DNA sequence?

13. All of the DNA and mRNA sequences in Model 1 have ellipses (…) on one or both ends of the sequences shown. Propose an explanation for this use of this symbol in that context. 14. The amino acids produced from sequence 1 and sequence 2 in Model 1 do not have ellipses on the end of them, however the amino acids produced from sequence 3 and sequence 4 do have ellipses. Propose an explanation for the use or absence of the ellipses on these sequences.

Genetic Mutations

3

Model 2 – Comparing Substitution Mutations Original DNA:

… T A C C C T A G G A A T A T C A A A…

mRNA: A U G G G A U C C U U A U A G U U U… Amino acid: Met Mutation A:

Gly

Ser

Leu

stop

… T A C C C T A G G A A A A T C A A A….

mRNA: A U G G G A U C C U U U U A G U U U… Amino acid: Mutation B:

Met Gly Ser Phe stop … T A C C C T A G C A A T A T C A A A….

mRNA: A U G G G A U C G U U A U A G U U U… Amino acid: Mutation C:

Met Gly Ser Leu stop … T A C A C T A G G A A T A T C A A A…

mRNA: A U G U G A U C C U U A U A G U U U… Amino acid:

Met stop

Mutation D: T A G C C T A G G A A T A T C A A A… mRNA: A U C G G A U C C U U A U A G U U U… Amino acid: No protein will be translated because there is no start codon. 15. For each of the mutations A – D in Model 2, circle the substitution that occurred by comparing the mutated DNA with the original DNA. 16. As a group, describe the range of changes in the amino acid sequence that can result from this type of mutation.

4 POGIL™ Activities for AP* Biology

17. Gene mutations can be positive, negative or neutral. Suppose that the normal gene in Model 2 produced a polypeptide that was necessary for cellular respiration. a. Choose a mutation from those in Model 2 that would be neutral for a cell. Explain your reasoning by relating the mutation to the cellular respiration process. b. Choose a mutation from those in Model 2 that might be positive for a cell. Explain your reasoning by relating the mutation to the cellular respiration process. c. Choose a mutation from those in Model 2 that might be negative for a cell. Explain your reasoning by relating the mutation to the cellular respiration process.

Read This! Mutations are the source of all new alleles in nature. Variations in alleles lead to variations in organisms within a population. Positive mutations lead to the organism having a better chance of survival, which means the mutation may be passed on to the offspring. Negative mutations may lead to an early death— probably before the organism can produce offspring. Therefore, changes in alleles from one generation to another form the basis of evolution. 18. Which types of mutations, positive, negative or neutral, are most likely to be seen in offspring several generations after the mutation occurred? Explain your reasoning. 19. Consider the following scenarios. State whether the mutation is likely to be passed on to the offspring of the organism. Explain your reasoning. a. A single bacteria cell contains a positive mutation in its DNA. b. A skin cell on a cat contains a positive mutation in its DNA.

c. A sperm cell in a whale contains a positive mutation in its DNA.

Genetic Mutations

5

20. All cells have DNA errors due to the mistakes that occur each time DNA is replicated prior to cell division. There are proofreading enzymes in cells that correct many of these mistakes, but on average, 3 – 5 errors are found in DNA after each replication. a. If each cell has multiple mutations, why do most of us have normally-functioning tissues and organs?

b. Why is only a tiny subset of these mutations passed on to our children?

6 POGIL™ Activities for AP* Biology

Extension Questions 21. A gene mutation is a change in the sequence of nucleotides that occurs during cell replication (mitosis and meiosis) within a single coding section of DNA. Mistakes can also occur in the transcription of mRNA or the translation of a polypeptide. However, these changes are not considered to be mutations, because they are not permanent changes to the cell. Explain why “mistakes” in transcription or translation are not as serious as mutations in a gene.

22. Insertion and deletion mutations are said to cause shifts in the “reading frame” (the sets of three nucleotides) of the mRNA. Substitution mutations do not cause these so-called frameshifts. Explain why insertions and deletions are called frameshift mutations, using the terms reading frame, codons, and amino acids in your answer.

Genetic Mutations

7

POGIL 16 Genetic Mutations-S.pdf

Page 1 of 7. Genetic Mutations 1. Genetic Mutations. What mistakes can occur when DNA is replicated? Why? The genes encoded in your DNA result in the production of proteins that perform specific functions. within your cells. Various environmental factors and spontaneous events can lead to changes in genes.

440KB Sizes 0 Downloads 597 Views

Recommend Documents

POGIL 16 Genetic Mutations-S.pdf
There was a problem previewing this document. Retrying... Download. Connect more apps... Try one of the apps below to open or edit this item. POGIL 16 ...

POGIL ISOTOPES.pdf
Electron cloud. Nucleus. Electron cloud. Nucleus. Electron cloud. Nucleus. Electron cloud. Nucleus. Electron cloud. Nucleus. Electron cloud. Nucleus. Page 1 of ...

POGIL ISOTOPES.pdf
Model 1. Isotopes of Hydrogen. Symbol 1. 1H 2. 1H 3. 1H. Atomic Diagram. with Name ... Electron cloud. Nucleus. Electron ... Page 1 of 1. POGIL ISOTOPES.pdf.

POGIL - Ecological Pyramids.pdf
per square meter per year. Blue jays (omnivore). Caterpillars (herbivore). Oak tree leaves (producer). Sunlight hitting Earth's surface = 3,190,000 kcal. 470 kcal. 4,000 kcal. 25,500 kcal. 1. A unit used to measure energy is the kcal. a. What is the

POGIL ISOTOPES.pdf
Page 2 of 5. 2 POGILTM Activities for High School Chemistry. 1. Refer to Model 1. What subatomic particles do the following symbols represent in the Atomic.

POGIL - Photosynthesis and Respiration.pdf
What is the relationship between photosynthesis and cellular respiration? Why? ... would happen to the supply of those foods if the sun's energy was no longer ...

Molarity POGIL key.pdf
lemonade mixture consists of several molecules. The dissolved sugar molecule (solute) is. indicated with a •. 1. Refer to Model 1. a. What is the solvent in this scenario? ___water___ The solute? ___sugar___. b. Lemonade Solution 1 has (more/less/t

POGIL - Energy Transfer.pdf
Retrying... POGIL - Energy Transfer.pdf. POGIL - Energy Transfer.pdf. Open. Extract. Open with. Sign In. Main menu. Displaying POGIL - Energy Transfer.pdf.

Genetic Counselors' Religiosity & Spirituality: Are Genetic ...
Abstract Although there is evidence that the religious. beliefs of genetic counselors (GCs) can induce internal .... perform the regressions, we used a dummy code for. whether or not an individual is a genetic counselor. In ... Arkansas, Oklahoma, Lo

POGIL Population Growth (1).pdf
For example, New York City has 8.3 million people distributed over a land area of only 305. miles2. , making it the most dense city in the nation. Model 4- Factors ...

Abstract Contents Genetic Programming - Cartesian Genetic ...
Jul 7, 2010 - Dept of Computer Science. Memorial ... ❖The automatic evolution of computer programs .... P ro ba bilit y o f S uc c e s s f o r 10 0 R uns. 0.2. 0.4.

Abstract Contents Genetic Programming - Cartesian Genetic ...
Jul 7, 2010 - Abstract. Cartesian Genetic Programming is a form of genetic ... 3. / Divide data presented to inputs (protected) ..... The To Do list isn't too big.

Titration POGIL 2015.pdf
After the addition of some strong acid, but before the equivalence point, some of the weak. base has been converted to its conjugate acid. The solution is a buffer ...

POGIL Population Growth (1).pdf
Populations are often clumped together in area because of access to resources, such as water, food and shelter. The. population density of any given area is ...

man-64\pogil-molarity-key.pdf
... 28 Chemistry Molarity Pogil Answer Key. 24. PDF Ebook : Pogil Answer Key Molarity Lemonade. 25. PDF Ebook : Molarity Pogil Extension Questions Answers.

POGIL 29 Neuron Structure-S.pdf
and features of neurons, which are the primary cells in the nervous system, enable animals to experience. all of the fi ve senses; fi nd food, mates, and shelter; ...

POGIL-Newton's Third Law.pdf
Sign in. Loading… Page 1. Whoops! There was a problem loading more pages. Retrying... POGIL-Newton's Third Law.pdf. POGIL-Newton's Third Law.pdf. Open. Extract. Open with. Sign In. Main menu. Displaying POGIL-Newton's Third Law.pdf.Missing:

POGIL 29 Neuron Structure-S.pdf
Challenge Battle ofthe Bloodlines S27E02 Bad Blood.Information society. Portal video game- Download.Portal video game.Dinnerat. noon.Portal video game.Portal video game.Freeze 2 android.Aviciitrue 320kbps. Mirroredgereloaded.021145632.Star wars mach.

POGIL Population Growth (1).pdf
For example, New York City has 8.3 million people distributed over a land area of ... POGIL Population Growth (1).pdf. POGIL Population Growth (1).pdf. Open.

POGIL 29 Neuron Structure-S.pdf
and features of neurons, which are the primary cells in the nervous system, enable animals to experience. all of the fi ve senses; fi nd food, mates, and shelter; ...

POGIL-Newton's Third Law.pdf
Complete model 1, including creating an image for example D, completing the “in words” column for C and E, the. “forces” column for C, D and E and the “net ...

POGIL - Enzymes and Cellular Regulation.pdf
Add a line to the graph in Model 1 that shows a prediction for gastric lipase activity. 11. Antacids work by neutralizing acids, bringing the pH of the stomach to a ...

man-64\pogil-extension-questions-molarity-answers.pdf
Answers in this website. ... clicking the connect to download Pogil Extension Questions Molarity Answers, you could begin to. get the book for your very own.