Copy of Mouse Genetics Gizmo Student Exploration Sheet PDF

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hope this helps. I answared all of them to the best of my ability. Hope this helps and hope you ace your class....

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Name: _Kai Davidson_____________________________________ ________________________

Date:

Student Exploration: Mouse Genetics (One Trait AND Two Traits) Vocabulary: allele, DNA, dominant allele, gene, genotype, heredity, heterozygous, homozygous, hybrid, inheritance, phenotype, Punnett square, recessive allele, trait Gizmo Warm-up Heredity is the passage of genetic information from parents offspring. The rules of inheritance were discovered in the 1 century by Gregor Mendel. With the Mouse Genetics (One T Gizmo™, you will study how one trait, or feature, is inherite 1. Drag two black mice into the Parent 1 and Parent 2 box Click Breed several times. What do the offspring look lik [All of the offspring will have black fur ] The appearance of each mouse is also called its phenotype.

2. Click Clear, and drag two white mice into the parent boxes. Click Breed several times. What is the phenotype of the offspring now? [ All offspring are white fured. ]

3. Do you think mouse offspring will always look like their parents? [Yes. But it will different ways the offspring will very from the parent. ] Explain: [ For example if your mom has sharp ears and your dad has flat ears, you could get a mixture of both types of ears. ]_

Activity A: Patterns of inheritance

Get the Gizmo ready: ● Click Clear. ● Drag a black mouse and a white mouse into the parent boxes, but don’t click Breed yet.

Question: What patterns are shown by offspring traits?

1. Predict: What do you think the offspring of a black mouse and a white mouse will look like? [ I think most of them will be black and some will be white ] 2. Observe: Click Breed several times. What do you see? [ they are all black ]

3. Observe: Drag two offspring into the Holding Cages. These mice are called hybrids because their parents had different traits. Click Clear, and then breed the two hybrids. What do you see now? [4 black mice and 1 white mice. ]

4. Experiment: Turn on Show statistics. Click Breed until there are 100 offspring. How many offspring were black? [ 76 ]

How many were white? [ 24 ]

5. Explore: Try other combinations of mouse parents. Write the results of each experiment in your notes. When you have finished, answer the following questions. (Note: You can refer to the parents as “pure black,” “pure white,” or “hybrid.”) A. Which parent combination(s) yield only white offspring? [Both parents are white mice ] B. Which parent combination(s) yield only black offspring? [ Both parents are black mice ] C. Which parent combination(s) yield a mixture of black and white offspring? [ A parent being, for example Ff and the second parent will be ff. ] Get the Gizmo ready: Activity B: Genetics basics

● Click Clear. ● Drag a black mouse and a white mouse into the parent boxes.

Introduction: Inherited traits are encoded on a molecule called DNA (deoxyribonucleic acid). Genes are segments of DNA that control a particular trait. Most genes have several different versions, or alleles. The genotype is the allele combination an organism has. Question: How do alleles determine fur color? 1. Observe: Turn on Show genotype. Move your cursor over a mouse to see its genotype. A. What is the genotype of the black parent? [FF ] White parent? [ ff ]

These mice are homozygous for fur color, meaning both alleles are the same. B. Click Breed. What is the genotype of the offspring mice? [Ff ] These mice are heterozygous for fur color, meaning the alleles are different.

2. Analyze: Dominant alleles are always expressed when present. Recessive alleles are not expressed when the dominant allele is also present. Look at the two alleles for fur color. A. Which allele is dominant, and which fur color does it produce? [ F which is black fur ] B. Which allele is recessive, and which fur color does it produce? [f which is white fur ]

3. Predict: Place two of the Ff offspring into the Holding Cages. Click Clear, and then place them into the parent boxes. A. Which allele(s) could the offspring inherit from parent 1? [F and f ] B. Which allele(s) could the offspring inherit from parent 2? [F and f ] C. What are the possible genotypes of the offspring? [FF, Ff, and ff ]

Experiment: Click Breed several times, and look at the genotypes of the offspring. Did you find all the predicted genotypes? [Yes I did find the prediction. Because the parents were Ff. This means that their offspring had a chance of being any combination of a genotype.] Get the Gizmo ready:

Activity C:

● Click Clear. ● Drag a black mouse and a white mouse into the parent boxes.

Modeling inheritance

F

F

Ff__ _black ___ Ff__ Ff___ black_ _black f ___ ___ Question: How do scientists predict the genotypes of offspring? f

Ff black

1. Model: Scientists use a Punnett square to model the different possible offspring genotypes from a parent pair. The parent genotypes are written across the top and side of the square, as shown. The four possible offspring genotypes are then filled in. F

F

f

Ff black

Ff black

f

Ff black

Ff black

The first square is filled in for you. Fill in the remaining squares with both genotype and phenotype. D. What are the genotypes of the offspring? [ Ff ] E. What percentage of the offspring will have black fur? [ 100 percent of the offspring ] F. What percentage of the offspring will have white fur? [0 percent will have white fur ]

2. Experiment: Click Breed several times. Were your predictions correct? [Yes my predictions were correct. ]

3. Model: Use the Punnett squares below to model each parent combination. After filling in each Punnett square, predict the percentages of black and white offspring.

Parent 1: Heterozygous black (Ff) Parent 2: Heterozygous black (Ff) __F__ _F__ _

__f__

_FF___ ____ __Ff__ ____

Parent 1: Heterozygous black (Ff) Parent 2: Homozygous white (ff) __F__

__f__

__f__

_Ff___ ____

_ff___ ____

__f__

__Ff__ ____

_ff___ ____

_f___ __ff__ ____ __ff__ ____

Predicted % black offspring: [ ] Predicted % black offspring: [ ] Predicted % white

offspring: [ ] Predicted % white offspring: [ ]

Now go to the second Gizmo! Student Exploration: Mouse Genetics (Two Traits) Vocabulary: allele, genotype, phenotype, probability, Punnett square

Activity A: Exploring inheritance

Get the Gizmo ready: ● Click Clear. ● Turn on Show genotype.

Question: What patterns appear when two traits are inherited? 1. Observe: Breed a black-fur, black-eye mouse with a white-fur, red-eye mouse. Click Breed several times, and then drag two of the offspring into the Holding Cages below. Move the cursor over a mouse to see its genotype, or allele combination. i. What is the genotype of the black-fur parent? [FF and EE ] ii. What is the genotype of the white-fur parent? [ ff and ee ] iii. What are the genotypes of the offspring? [Ff and Ee ]

2. Analyze: The probability of an event is the likelihood that it will happen. Probability can be expressed as a percentage, such as 75%, as a decimal (0.75), or as a fraction (3/4). What is the probability that an offspring mouse will have black fur and black eyes? [ It will be 100% that the mice will have black fur and 0% of black colored mice will have red eyes. ]

3. Predict: Click Clear, and move the two mice from the Holding Cages into the parent box. What do you expect the offspring of these mice to look like? [That they will have all white fur and no red eyes. I picked a mice with white fur and black eyes as parent #1 and parent #2 is a white fur mouse with red eyes. ]

4. Experiment: Click Breed, and record the genotypes of the offspring on a sheet of paper. Repeat this several times to see a variety of offspring. What genotypes do you see? [ ff and Ee ] 5. Extend: Turn on Show statistics, and click Breed until there are 100 offspring. i. How many offspring have black fur and black eyes? [ 100% ] ii. How many offspring have black fur and red eyes? [0 % ] iii. How many offspring have white fur and black eyes? [ 100% ] iv. How many offspring have white fur and red eyes? [ 0% ]

Activity B: Probability and genetics

Get the Gizmo ready: ● Click Clear. ● Use the Gizmo to create an Ff Ee parent and an Ff ee parent.

Question: When traits are inherited, what is the probability of each offspring’s genotype?

4. Model: To determine the probability of a trait combination such as black fur and red eyes, consider each trait separately. Fill in the Punnett square for each trait. Then determine the probability of black fur and the probability of red eyes. Express each probability as a fraction.

Parent 1 fur genotype: Ff Parent 2 fur genotype: Ff ____

____

____

Parent 1 eye genotype: Ee Parent 2 eye genotype: ee

____

____ ____

____ ____

____ ____

____ ____

____

____

____

____ ____

____ ____

____

____ ____

____ ____

[ ] [ ]

[ ] [ ]

Probability of red eyes: Probability of black fur:

5. Predict: Now multiply the probabilities together to find the probability of black [ ]

[ ] fur and red eyes. Express your answer as a fraction and as a percentage:

or

[ ]%

6. Experiment: Turn on Show statistics. Check that the parent mice genotypes are Ff Ee and Ff ee. Click Breed until there are 500 offspring. A. How many of the offspring had black fur and red eyes? [195 ] B. What percentage of offspring had black fur and red eyes? [ 39 ] Activity C: Expanded Punnett square

Get the Gizmo ready: ● Click Clear. ● Use the Gizmo to create two Ff Ee parents.

Introduction: A second method for calculating the probability of each offspring’s genotype is to use an expanded Punnett square. Question: How can a 4x4 square model the inheritance of two traits? 4. Model: Each parent mouse will contribute one allele for fur color and another for eye color. If a parent mouse is Ff Ee, there are four possible allele combinations the parent could pass to its offspring: FE, Fe, fE, and fe. The combinations are written along the top and sides of the expanded Punnett square, as shown below. Fill in the empty spaces to complete the square. Then write the probability of each offspring’s phenotype (physical appearance) in the spaces to the right. Express each probability as a fraction and as a percentage.

[8] [16 ] Black fur, black eyes: or [50 ] %

[4 ] [16 ] Black fur, red eyes: or [ 25 ] %

[3 ] [16 ] White fur, black eyes: or [ 19 ] %

[1] [16 ] White fur, red eyes: or [6 ] %

5. Experiment: Check that Show statistics is turned on. Be sure there are two Ff Ee parents. Click Breed until there are 500 offspring. Write the results in the table below. Trait combination: Number:

Black fur, black eyes [276 ]

Black fur, red eyes [ 92 ]

White fur, black eyes [101 ]

White fur, red eyes [31 ]

Percentage:

[ 55 ]

[ 18 ]

[20 ]

[6]...