Diocesan Schools of Urdaneta
SAINT ANTHONY ABBOT ACADEMY
Villasis, Pangasinan
General Biology 2
Modular Activity #1 Pedigree Analysis
Lesson 2.4: Pedigree Analysis
A pedigree shows the presence or absence of a trait according to the relationships between parents, siblings, and
offspring. It can be used for any species, not just humans.
The information gained from pedigree analysis makes it possible to determine the nature of genes and
alleles associated with inherited human traits. You can determine if an allele for a trait is dominant or
recessive, autosomal or sex-linked. Sex-linked traits are traits that are linked with sex chromosomes. It can
be X-linked or Y-linked traits. An X-linked trait can NEVER be passed from father to son on the other
hand, Y-linked traits will NEVER affect females.
The following are the mode of inheritance:
1. X-Linked Recessive Traits
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Both males and females can be affected, but the trait is much more common in males.
Affected males transmit the allele to ALL of their daughters and NONE of their sons
Daughters of affected males are always carriers (not affected) unless mother also has the allele
Affected female will have affected sons.
2. X-Linked Dominant Traits
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If the trait is dominant, it will be expected to occur more often in females.
ALL daughters of an affected male will be affected (NO carriers)
It cannot be passed on from father to son.
3. Y-Linked Traits
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No affected females
ALL sons of affected males are also affected.
Diocesan Schools of Urdaneta
SAINT ANTHONY ABBOT ACADEMY
Villasis, Pangasinan
Pedigree Analysis Activity #1
Name:____________________________
Date:___________________
Grade level & Section:______________
Directions: Read the paragraph and answer the questions. Write your answer on a separate paper (1 whole pad
paper).
Situation: Hemophilia is an example of a sex-linked disorder. Two genes carried on the X chromosome help
control blood clotting. A recessive allele in either of these two genes may produce hemophilia. The pedigree
shows the transmission of hemophilia through three generations of a family.
1. Whose mothers are definite carriers of the gene?
2. Why did the sons of Person 3 not able to inherit the trait?
3. How could Person 12 have hemophilia if both parents are not affected?
Diocesan Schools of Urdaneta
SAINT ANTHONY ABBOT ACADEMY
Villasis, Pangasinan
Performance Activity #2
Pedigree Analysis
Pedigree Diagram analysis of your family from first to second generation. (Individual performance task)
Make your own pedigree analysis starting from both your parents and to their offsprings (including you).
Observe what common trait your family share the most then plot it in your own pedigree analysis
Example of traits (for reference): Colorblind mother or sibling, attached earlobe or free earlobe among you.
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Important instructions to follow
Print your own Pedigree Analysis on a LONG COUPON BOND PAPER
Landscape Page Orientation
Font: Times new roman Font Size: any size but make sure it is neatly placed inside a diagram.
Place your full name on the left side then grade level & section below it.
Deadline: March 15, 2024
The following below are the activities you need to pass on or before March 15, 2024:
1. Activity 1: Checklist of your family Traits
2. Modular Activity 1: Pedigree Analysis (hemophilia)
3. PETA #2 PEDIGREE ANALYSIS OF YOUR FAMILY
Pedigree Analysis Rubric
Criteria
Pedigree Analysis’
content
0-10 POINTS
The student failed
to complete two
generations of
his/her family’s
pedigree.
Criteria
Accuracy on
choosing
appropriate
pedigree diagrams
0-10 POINTS
The student failed
to properly choose
a pedigree diagram
on his/her pedigree
analysis.
Criteria
Creativity and
Neatness
0-3 POINTS
The student did not
place any creativity
design and the
pedigree diagram is
not properly
aligned.
Overall points: 50 POINTS
Prepared by: Jennifer C. Orogo
11-15 POINTS
The student was
able to trace some
traits of his/her
family’s pedigree
but only one
generation.
11-15 POINTS
The student was
able to choose a
pedigree diagram
but only few on
his/her family
members.
4-7 POINTS
The student was
able to design
his/her pedigree
diagram and neatly
aligned.
16-20 POINTS
The student was
able to excellently
trace traits from
first to second
pedigree generation
16-20 POINTS
The student was
able to excellently
choose appropriate
pedigree diagrams
from first to second
generation.
8-10 POINTS
The student
displayed high
creativity design to
his/her pedigree
diagram and it is
properly aligned.