Sex-linked Trait
Grade level or other prerequisites for activity High School
Standards:
 Colorado 2.7 High School (Genetics)

Physical and behavioral characteristics of an organism are influenced to varying
degrees by heritable genes, many of which encode instructions for the production of
proteins

NSES Life Science Standard C
Learning objectives:
Students will be able to (SWBAT):
1) Identify sex-linked traits and sex determination,
2) Explain the history behind the royal family and hemophilia, colorblindness this
doesn’t describe what concepts are to be learned.
3) Complete a Punnett square given parent traits to predict offspring traits
4) Carry out a virtual lab by collecting data and interpreting results by applying what
they learned in class
Objectives of the lab:
a.)
Construct and analyze Punnett squares for monohybrid genetic
crosses involving sex-linked traits
b.)
Perform fly mating and analyze the offspring that result from each
cross
c.)
Explain why sex-linked traits appear more often in males than in
females
Balgopal_5E lesson plan template
Materials
Students should watch video on http://www.sophia.org/tutorials/sex-linked-traits--2 at the bottom
of the page and take notes before class and we will complete the worksheet in class together.
Print outs of the worksheet is needed for each student. Work sheet can also be found at the link
above.
Then complete the virtual lab found at:
http://www.mhhe.com/biosci/genbio/virtual_labs/BL_15/BL_15.html
Student Activity
Engage
Discussion around prompts: How
many of you have heard that more
guys are color blind than girls? If
color blindness is a genetic trait, then
why do more guys get it than girls?
Does sex matter? Why would sex
matter in terms of how a trait is
inherited?
Teacher Activity
Teacher will start class by:
0) Do a notebook check for the notes
to make sure students watched video
before class. If not, student will have
to watch video and complete
worksheet on their own
1) reviewing the learning
objectives
2) Listing discussion prompts
on the board and leading a
class discussion.
Explore
Fill out worksheet together as a class
to review materials from the video
Students will be able to use their
science notebooks where they took
notes on from the video they watched
before class. Students will come up
individually or as a pair to answer the
question.
What is the purpose of the worksheet?
Will they use any resources to help
them do this? Science notebook?
Textbook?
Balgopal_5E lesson plan template
Have worksheet set up on a smart
board to have students come up and
fill in the worksheet.
Popcorn read the reading portions of
the worksheet
Encourage students to help answer
the questions..
Draw names out of a cup or take
volunteers to come up to answer the
question. If student is not
comfortable in answering a question
on their own, have them take a
buddy
Explain
Students will use their own computers
to go the website listed above. They
will in a group of two complete a
virtual lab. They will use their science
notebook to write down results of
their lab individually
Walking around helping students
through the lab, asking questions to
make sure they are interpreting their
results using what they have learned
and doing the calculations correctly.
Elaborate
Solve and answer the 8 questions
found under the ‘Journal’ Tab with
their lab partner. Replace “complete”
(which is task-oriented) with a more
descriptive verb that is learningoriented.
Again, walking around and helping
out students that may be stuck and if
they have a wrong answer, ask them
why they think so.
Evaluate
Discuss lab results among students
and go over the results with the class.
Have students come up with their lab
partner to share their results to one of
the eight questions.
Go over lab results, interpretations
and how the calculations were done.
Explain why some experiments
resulted differently. How you can
modify this lesson so it’s about
learning the concepts and not about
getting the right answer? What if you
asked students to write explanations
of why they may have gotten a
‘wrong’ answer? This way, they can
still get full points.
Assessment
Formative
Informal: Worksheet will go into student’s science notebooks after completion as
notes.
Summative: Questions that go along with the lab.
Anticipated misconceptions/alternative conceptions:

A child will get all genetic materials from their parents passed down, not just half

There are chromosome specific diseases
Balgopal_5E lesson plan template

Boys are more susceptible to X-linked diseases while girls won’t get any Y-linked diseases
Accommodations/modifications
The video that students will see prior to class will have both auditory and visual aid.
Answers to the worksheets will be hand written on the board or displayed with a doc cam
Virtual lab comes with auditory option and provides a minds-on activity.
Discussion prompts will be displayed on board
Students will have the chance to revise their answers and explain how and why they did.
Lesson Adapted from: http://www.sophia.org/tutorials/sex-linked-traits--2
Balgopal_5E lesson plan template