Genetics and Punnett Square
YouTube Link: https:
youtu.be/n55mxURQWlE
Heredity How are traits passed from parents to offspring?
A trait is a characteristic such as color or size that is inherited by an offspring from its parents. The genes that control a trait come in pairs, one gene from each parent. We represent these gene pairs by writing a combination of two capital or lowercase letters. For example, if one parent contributes a gene for blue eyes (C), and the other parent contributes a gene for
own eyes (c), then we write the offspring's eye color trait as Cc. This combination of the two genes that determine the trait is called a genotype.
Each letter in a gene pair stands for one form of the trait. The forms of a trait are called alleles. In this example, the alleles are blue eye color and
own eye color.
The two types of alleles are dominant and recessive. A dominant allele is written as a capital letter, and a recessive allele is written as a lowercase letter. If a gene pair contains a dominant allele, then the offspring will show this dominant trait. Recessive alleles can only show up when there is no dominant allele present to suppress them. The form that shows up is called a phenotype.
In this Virtual Lab you will use a Punnett square to find possible gene combinations and to create a fictitious animal.
Objectives:
· Identify the phenotypes of offspring from a genetic cross.
· Use Punnett squares to identify the outcomes of genetic crosses.
Video Procedure:
1. Watch the Video
2. Answer the following Questions:
a. What is the difference between a genotype and a phenotype?
. How are the alleles and traits related? Explain using an example
c. In pea plants, purple flowers color (P) is a dominant allele, while white flower color (p) is recessive allele. If a pea plant has the genotype Pp, what is its phenotype? Explain your answe
3. Fill in the following for Animal 1
Trait
Selected Genotype
Selected Phenotype
Eyes
Ears
Nose
Mouth
Fu
Feet
4. Fill in the following for Animal 2
Trait
Selected Genotype
Selected Phenotype
Eyes
Ears
Nose
Mouth
Fu
Feet
5. Fill in the following for animal 3
Trait
Selected Genotype
Selected Phenotype
Eyes
Ears
Nose
Mouth
Fu
Feet
6. Do a punnet Square for the eyes given the genetic code “Ee x ee”
How Mutations Work
For this assignment, complete the worksheet on the following page. Submit as directed by your instructor.
Grading Criteria
Basic Requirements (the assignment will not be accepted or assessed unless the follow criteria have been met):
· All five questions are answered.
· The answers to each question are thorough and co
ect.
Ru
ic: How Mutations Work
Outcome: Describe the conversion of DNA to RNA to proteins
Criteria
Ratings
Pts
Recognize the impact of DNA mutations.
Answered all 5 questions with complete sentences.
5.0 pts
Answered 4 out of the 5 questions with complete sentences.
4.0 pts
Answered 3 or fewer questions, or did not answer questions with complete sentences.
0.0 pts
5 pts
Summarize the process of genetic translation.
Answered 4-5 of the questions thoroughly and co
ectly.
5.0 pts
Answered 2-3 of the questions thoroughly and co
ectly.
4.0 pts
Answered less than 2 questions co
ectly, or did not expand upon written ideas.
0.0 pts
5 pts
Total points: 10
Attribution
CC LICENSED CONTENT, ORIGINAL
· Authored by: Lumen Learning License: CC BY: Attribution
CC LICENSED CONTENT, SHARED PREVIOUSLY
· Differentiated Mutation Worksheet. Authored by: Ppickwell. Located at: https:
www.tes.com/teaching-resource/differentiated-mutation-worksheet XXXXXXXXXXLicense: CC BY-SA: Attribution-ShareAlike
Normal DNA sequence:
Sickle cell DNA sequence:
Sickle-cell anaemia. DNA Mutations
What is the difference between sickle-cell blood cells and normal
lood cells?
What is the difference between sickle-
cell haemoglobin and normal haemoglobin?
What is the difference between sickle-
cell amino acid sequence and normal amino
acid sequence?
What is the difference between sickle-cell
DNA sequence and normal DNA sequence?
Use all of this to explain in your own words what a mutation is and how it can cause a
genetic disease.
Normal DNA sequence:
Sickle cell DNA sequence:
Sickle-cell anaemia. DNA Mutations
What is the difference between sickle-cell blood cells and normal
lood cells?
What is the difference between sickle-
cell haemoglobin and normal haemoglobin?
What is the difference between sickle-
cell amino acid sequence and normal amino
acid sequence?
What is the difference between sickle-cell
DNA sequence and normal DNA sequence?
Use all of this to explain in your own words what a mutation is and how it can cause a
genetic disease.