Project: ‘Let’s Make a Baby' 

Learning Objective:
NGSS: MS-LS3-2. Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation.

Background:

Have you ever wondered why each person looks different from everybody else, even brothers and sisters?  We all look unique because of the large variety of traits existing in our human population.  

 

Imagine if you were to have kids of your own!  Which of your traits do you think would appear in your children?  The following project will help you find one possible answer to this question.

 

Directions:

Part 0:

  1. Study the Facial Traits Examples.
  1. See if you can identify those traits for which you seem to be dominant, recessive, and hybrid (heterozygous).  For some traits you probably won't be able to tell, and that's ok for now.

Part 1:

  1. Facial Traits:
  1. Make a copy of the document: Facial Traits Data
  2. Put your SECRET CODE in the box that says either FEMALE (if you are biologically a female) or MALE (if you a biologically a male).  
  3. Complete the genotype and phenotype columns that correspond to you (either 'Mom' or 'Dad'):
  1. For each of the traits that are listed, provide a one or two word description of your own phenotype.  (for example, 'brown eyes', or 'uni-brow')
  2.  Use the information on the facial traits document to identify your possible genotypes (i.e. Hh or HH, of hh).  If you are able to easily determine your genotype, enter the corresponding alleles into the genotype column.  (hint:  a recessive phenotype indicates two recessive genes in your genotype!)
  3.  For some Mendelian traits you won’t know for sure whether your genotype is homozygous-dominant or heterozygous.  We can then infer that one of your alleles is dominant.  If the trait has a long history in both sides of your family, then the other allele is probably also dominant.  But, if you are unsure, then you will need to flip a coin to make a guess about the second allele.  After you have done this, indicate the remaining genotypes on your chart.
  1. Make a Paper Copy of the Facial Traits Data to serve as the SECRET PARENT sheet:
  1. Show your completed electronic copy of the Facial Traits Data to your teacher.  He/She will then give you a paper copy of the same document.  
  2. Do NOT write your name on this page.  Only write down your secret I.D. in the appropriate spot.  
  3. Copy your list of genotypes onto this chart.  Write very neatly so that anyone else could easily read your list.
  4. Submit the "Secret Parent" page to your teacher.  Later, your teacher will exchange this information for a classmate's "Secret Parent" page which you can then use as your "mate" to complete this project.
  1. Partner's (Mate's) Data
  1. Your instructor will give you a "Secret Parent" sheet that was completed by another student.  
  2. Copy the information from the "Secret Parent" sheet into your own Facial Traits Data worksheet in the appropriate column.  If you are the 'mother' then the 'Secret Parent' data would go in the 'father' column, and vice-versa.
  1. Offspring Traits Data:
  1. Use the information about YOU and your Secret Partner determine what the genotype and phenotype of your offspring are.  
  2. For some traits, where both parents are homozygous, you can easily determine what your child's genotype will be.  Go ahead and enter those genotypes in the Child's Genotype column.
  3. For other traits, where one or both parents are heterozygous, you won't know for sure which alleles will be passed on to your child.  Toss a coin for each heterozygous combination to determine which allele will be passed on.  Enter these alleles into the remaining genotype spaces for your child.
  4. Now complete the Child's Phenotype column by using one or two words to describe the phenotype for each of your child's traits.  (For this step, it might again be helpful to Study the Facial Traits Examples.
  1. Offspring Graphic Facial Models (Examples)
  1. You have two options for creating the facial models of your offspring:
  1. Option 1:  Use the blank LMaB: Child Face Template (Print Version) page provided by your teacher to illustrate your child.  
  1. Be sure to label each genotype/phenotype
  1. Option 2:  
  1. Use Mugshot Creator to create a template of your child.
  1. The following rules apply for using mugshot creator:
  1. You should take a screenshot of the created mugshot, and paste it into the LMaB: Child Face Template where appropriate.
  2. You still need to color the face by hand and add appropriate details by hand (anything you can't do with the mugshot creator.
  3. Label the LMaB: Child Face appropriately 
  1. Be sure to base your drawings only on the genetic information you've collected.
  2. Submit your illustrations to your teacher.
  1. Display:  Eventually, the picture you create of your ‘child’ will be displayed in our classroom along with those of your classmates’ children.  Then you’ll be able to compare with one another and to identify which traits seem more dominant than others.  You might even be able to recognize if another child has some of your genes!