Name ______Date ______Hour _____

HW Packet Due October 16th

Lab / Due:______
Nature vs. / Data Table / 0 1 2
Nurture / Hypothesis / 0 1 2
Analysis / 0 1 2 3
Imcomp. / Page 4 / Do in class
Dom. / Page 5 / 0 1 2
Sex Link / Page 6 / Do in class
Practice / Page 7 / Do in class
Questions / Page 8 / 0 1 2
Page 9 / 0 1 2
Blood / Page 10 / Do in class
Type / Page 11 / 0 1 2
Genetic
Disorder #1 / Page 12 / 0 1 2 3 4 5

Your Points

Total Points Possible (20 pts)

Lab – Plant Phenotypes “Nature vs. Nurture”

Background:

Is heredity or environment more important in determining the kinds of traits that appear in offspring? For years scientists and psychologists have argued the relative importance of genes and how you are raised. Many studies of twins raised in different households have yielded surprising data. We will study the effect of genetics (the alleles you possess) and environment (the growing conditions) on a batch of corn seeds. The corn we will grow has two alleles, Green is dominant G = green and albino is recessive g = albino. The seeds you will use from parents plants were both heterozygous (Gg).

Hypothesis: By using a Punnet Square determine the possible genotypes of seeds produced by plants heterozygrous for green (Gg).

Procedure A:

  1. The teacher will prepare the sample of corn and albino plants into a classroom batch. .
  2. One dish will be marked “dark” and placed in the dark to grow. The other will be marked “light” and placed directly in the light.
  3. After 6 days, observe the plants that have grown from seeds in the batches. Note how many in each dish are green or albino (white or yellow). Combine your results totals with those of your classmates to complete Table 1.
  4. After your observations, place both batches in a light environment for several days. Moisten again if necessary.

Data Table 1:

CLASS RESULTS OF FIRST OBSERVATION

  1. Plants in DarkPlants in Light

# of green / # of albino / % of albino / # of green / # of albino / % of albino

Procedure B:

  1. After 2 days, observe the plants. Note how many in each dish are green or albino (white or yellow).
  2. Combine your results (totals) with those of your classmates to complete Data Table 2.

Data Table 2:

CLASS RESULTS OF SECOND OBSERVATION

  1. Plants in DarkPlants in Light

# of green / # of albino / % of albino / # of green / # of albino / % of albino

BACKGROUND

Corn plants require two factors in order to produce chlorophyll (green pigment in plants that attracts sunlight). They must have the proper gene combination (at least one dominant “G” gene) and also be exposed to light.

When doing any experiment, the more data or results you can gather, the more reliable your conclusions should be.

Analysis:

  1. Explain why the percentage of albino plants in the dark in the first observation did not agree with expected results obtained from the Punnett Square.
  1. What happened to the percentage of white plants when those in the dark were placed in the light for several days?
  1. Does the percentage of albinos at this point agree or come close to the expected percentage of albino’s in your Punnett Square? Explain.
  1. What happened to the percentage of albino plants when those in the light remained in the light for several more days? Explain.
  1. Explain how it is possible for environment to influence or temporarily change the expression of a gene.

Incomplete Dominance Practice Problems

  1. In guinea pigs yellow and white colors are incompletely dominant. They blend to form an intermediate cream color. Cross a cream colored female guinea pig with a yellow male pig.

1.

2.

3.

4.

5 & 6.

7.

  1. In certain species of chickens black feathers blends with white feathers to make offspring who are both black and white (speckled). Cross a black rooster with a white hen.

1.

2.

3.

4.

5 & 6.

7.

  1. In garden peas tall is incompletely dominant over short. Cross a hybrid plant with a homozygous tall plant.

1.

2.

3.

4.

5 & 6.

7.

  1. In the Japanese Four o' Clock, Mirabilis jalapa, red flowers are incompletely dominant over white flowers blending to form pink offspring. Cross a pink and a red flower.

1.

2.

3.

4.

5 & 6.

7.

SEX LINKED PRACTICE PROBLEMS

  1. Cross a colorblind (x-linked) male with a homozygous female with normal vision. What is the chance that they have a son who is colorblind?
  1. Cross a hybrid woman with hair and a bald man.
  1. In a cross between a white-eyed female fruit fly and red-eyed male, what percent of the female offspring will have white eyes? (White eyes are X-linked, recessive)

One Trait Crosses Practice Sheet

DISCLAIMER: BE CAREFUL EACH PROBLEM MAY BE DIFFERENT, A MONOHYBRID, A SEX-LINKED TRAIT, INCOMPLETE DOMINANCE OR MULTIPLE ALLELES (LIKE BLOOD TYPE)

  1. Color in chickens is often incompletely dominant. Cross a purebred black rooster with a purebred white hen. What are the genotypes and phenotypes of their offspring?
  1. Cross a hybrid red-eyed fruit fly (Drosophila melanogaster) with a homozygous white-eyed fruit fly. What are the genotypes and phenotypes of their offspring?
  1. Defective dentine is also the result of a dominant allele but it is carried on the X chromosome. The allele causes the teeth to wear down rapidly and usually only stubs remain by adolescence. Assume a female who has defective dentine (she is heterozygous) mates with a male who has normal teeth. What are the genotypes and phenotypes of their offspring?
  1. A heterzygous round seeded plant is crossed with a homozygous wrinkled seeded plant. What are the genotypes and phenotypes of their offspring?
  1. Muscular Dystrophy is a recessive X-linked trait. Cross a heterozygous female with a normal male. What are the potential genotypes and phenotypes of their offspring?
  1. Blue-green colorblindness is an autosomal recessive trait. Cross a hybrid male who can see blue and a female who is purebred blue colorblind. What are the genotypes and phenotypes of their offspring?

Also, explain how they could have they could have 10 children, all of whom could see blue.

  1. Show the cross for a pure breeding short haired guinea pig and a heterozygous long haired guinea pig. What are the genotypes and phenotypes of their offspring?
  1. There are three different alleles for PKU (a disease where because you cannot digest phenylalanine dangerous bi-products build up in your brain leading to severe retardation in homozygous individuals with the severe mutation in this gene). It is autosomal recessive.
    There are three different alleles: N = normal, M = mild mutation, and S = severe mutation. Both are inherited as autosomal recessive. Cross a Homozygous dominant man with a woman who is a hybrid of the mild and severe mutations. What are the possible genotypes of their offspring?

Blood Type in Humans

  1. Cross a man with Type AB blood with a woman with Type O.

1.

2.

3.

4.

5 & 6.

7.

  1. Cross a hybrid type B blood type with a homozygous type A.

1.

2.

3.

4.

5 & 6.

7.

**Could this pairing produce blood type O children? ______Explain:

  1. Cross a woman with Type AB blood with a man who is heterozygous for Type A blood. List the genotypes and phenotypes their children could possibly have.
  1. Cross a mother with Rh- blood with a father who is homozygous Rh+. What are the possible genotypes and phenotypes of their children?

Explain any problems that may arise in this couples second pregnancy.

My assigned genetic disorder is

Genetic disorders are caused by changes to DNA. These changes are either really small and involve only one tiny piece of DNA or really large and result in an entire missing chromosome. Either way, the affect on how someone lives their life can be dramatic. Additionally, some genetic disorders mean that a person may require someone to care for them their entire life.

Remember, your audience for this brochure is either someone who has just been diagnosed as having this genetic disorder or someone who is the parent or child of someone who has been diagnosed. Your teacher will show you examples of good brochures so you can be familiar with the qualities you should include in your brochure.

GENETIC DISORDER PROJECT ASSIGNMENT #1 –

  1. What are some of the symptoms of your assigned genetic disorder? Answer in complete sentences. Be sure to attach a copy of your references to the homework packet.

Answer in complete sentences. Be sure to attach a copy of your references to the homework packet.

1