Name:  Christina Stewart-Jordan

Subject:  Biology I - Genetics

Date:  July 15, 2008

Period:  2nd

Approximate Time:  50 minutes

Objective(s):

1.TSW recall their knowledge of Punnett Squares to predict sex-linked inheritance (DOK 1, Biology 5.d,e).

Do Now:

A woman (XX) and man (XY) mate and create four children.  What is the chance that the couple will have a male (XY) child? 

(5 minutes)

Set:

TSW review the previous day's lesson by completing and discussing the Do Now.  TTW state that the students will learn about Gregor Mendel and his contributions to science.  So, first we're going to take notes on Mendel and the three postulates he introduced for determining gene inheritance.  Then, we're going to continue making Punnett Squares, using them to determine sex-linked inheritance.

(5 minutes)

Procedure:

1.TTW will begin discussion of the Do Now.  TSW create their genotypes and phenotypes using ratios and fractions: genotypes- w/ fractions, phenotypes w/ ratios.

2.TSW take notes on Gregor Mendel:

i.  High school teacher & monk who studied pea plants in a monastery.

ii.  Considered the grandfather of genetics because he introduced the concept of a gene.

iii.  Studied heredity of garden peas from 1856-1863.  Scientists didn't recognize his works until the early 1900s.

3. Reasons Mendel chose to study pea plants:

i.  Small & easily produced, short life-span, pure breeding possible with variability in breeding

ii.  So, he had a testable hypothesis, a means to statistically test results, & have records of those results.

iii.  Mendel found seven different traits in the garden pea plants.

iv.  Started w/ Monohybrid Cross:  Looks @ different genes available for one trait.

4.Mendel's Three Postulates: 

a.  Genetic traits are controlled by genes, which exist in pairs in an organism.

b.  There is a dominant allele and a recessive allele for a gene.

c.  Genes separate randomly during the creation & fertilization of gametes.  (10 minutes)

5.TTW hand out activity on sex-linked inheritance & randomly call students to read (20 minutes).

6.TSW begin working practice problems on sex-linked inheritance until the bell rings

(5 minutes).

7.Closure

Closure:

TTW state that today the students looked at the contributions of Gregor Mendel and took notes on his postulates in determining sex-linked inheritance.  Then, the students demonstrated their knowledge of using a Punnett Square cross, by creating a Punnett cross for sex-linked inheritances.  Tomorrow, we begin looking at the inheritance of blood types, as we continue using the Punnett Squares.  Class is dismissed!  (5 minutes)

Assessment/ Evaluation:

Objective(s):

1.  TSW recall their knowledge of Punnett Squares to predict sex-linked inheritance (DOK 1, Biology 5.d,e).

Informal:  TTW listen and watch (M) as the students create and explain Punnett Squares of sex-linked inheritance (C).

Formal:  TSW will be graded on their classwork on sex-linked inheritance and (M) on their ability to create and explain Punnett Squares of those inheritances (C).  TTW record a grade of 10/10 in the grade book for completed assignments (D).