Exploring Hereditary Traits
Obrectlve
To derermine your possible genorypes tbr some
lpfrerired rrairs
Process 5kills
I
Pencil, PaPer
fme
6quirY
Observing, communicaring, inferring
Materials
mes
hof
ralirsel-
that
ders
3Py'
:hyrt of
:tus-
lav-
i.'
1 Make a rable with rhree columns and nine
rorvs. Head rhe columns Trair, phenorype,
and Possible Genorypes. In the-firsr column
lisr rhe nine rairs shown below.
In
2 rhe second column of the rable, write ves
or no depending on wherhe, oi not uou
'Work
possess. each rait.
wirh prrtrr.r. For
rrairs rhar you cannot observe" direcrly. ask
vour parrner for help. Each of rhe rraiii listed is conrrolled by a dominanr allele.
t
ir
:io,
:i--
-
t
:c
etus,
eda
t
iam:
lp
aS
rhan the second
Tongue-rolling (Rlz Stick our your rongue
and rr1. ro roll up rhe sides so rhat ihe
rongue.forms a U-shape.
Free earlobe (F): The lobe of the ear
hangs freelv below rhe poinr of arrach_
menr ro rhe head.
\Yidow's peak (lU/l:.The midpoinr of the
hairline along rhe fronr of tLe forehead
t
poinrs dor+.nward.
Straight thumb (N): !7hen exrended from
rhe palm of rhe hand, the ,op ,.g_.n,
of
rhe rhumb forms a srraight iin. "*i*-,t,.
borrom segmenr. (See figire.)
:s?
kledng
. !r!t linle finger (B): Thelas_r segmenr of rhe
limle finger bends in toward th.iine
fine.r.
t l,eft.-oueyight thumb ,rorring
(f), Vi.n
rhe hands are folded in , nrt,r'r"l
l;rh;",
'
the lefr rhumb crosses over
rhe ,igi;.
t Chi.n cleft (Cl: The cenrer of rheihin
an indenration resembling
h",
"
t (id-digital htair (H): Hair is presenr on
the middle section
of the'iingers.
t S,hort .big toe (T): "j.rnl,
The big
--- i, ,t orr.,
e ,*
a.;p ;-i',"pl..
roe.
'v
3 In the third column of the table, record
genowpes for each rrair, using
i:::I_"r:ible
rhe appropriare svmbols.
4 Compare your rrairs with those of your
classmares. which trait or ,rr*.-"i.
common among vour classmates?
rno*
Conclusions
1 Which observarions are evidence rhat
rhe
mosr common rrait may nor be
derermined
by the dominanr allele?'rXzl,i.f aoijn"nr
Ieles srudied today were most
common? "f-
2 Whar factors should b. .o;ri;;;.Jt.for.
comparing rhe frequency of rrairs
in the
classroom wirh rheii
popularion?
f..qu.n.i-in',t.
U.S.
Further lnquiry
Review all rhe traits studied and
discuss in class
possible adaptive advantage
of .r.f,ii"lr.''
t\
_--.'--#-
lnheritance Patterts and Human Genetics
177
N{e&fi$
&s{wffe$
Is the dominant
trait most prevalent?
Student Name:
Teacher/Class:
Date Collected:
1. Ear lobes
Total# surveyed
# of free ear lobes (dominant)
# of attached ear lobes (recessive)
2. White Forelock
Total # surveyed
# of people with white forelock (dominant)
# of people without white forelock (recessive)
3. Dimples
Total# surveyed
# of people with dimples (dominant)
# of people without dimples (recessive)
a'\
v
4. Thumb
Total # surveyed
# of people with straight thumb (dominant)
# of people with curved thumb (recessive)
5. Pinky
Total# surveyed
# of people with straight pinky (recessive)
# of people with bent pinky (dominant)
6. Mid-digit hair
Total# Surveyed
# of people with mid-digit hair (dominant)
# of people with no mid-digit hair (recessive)
7. Red-green color blindness
Total# Surveyed
# of people showing color blindness
# of people with normal color vision
O 2007 Stevens lnstitute of Technology,
^ Copyright
Center
for lnnovation in Engineering anO Sclence Education
All Rights Reserved
trtr#,6#Sgffirtrs
Is ttre dorninant
trait most prevalent?
Student Name:
Teacher:
Glass:
Date:
Sex (male or female)
Age (yrs)
Check all choices that
apply to you:
5.-\t
--/
color blind mother
color blind father
mom's father color blind
mom's mother color blind
dad's father color blind
dad's mother color blind
number of brothers
number of color blind
brothers
number of sisters
number of color blind
sisters
Survey Traits
Page
I of2
,ffi##g#gFggs
ls the dominant
trait most prevalent?
Home
Running the Project
lnstructions and Help
Schedule
Lesson Plans
Discussion Area/Data Submittal
Observable Genetic Traits
Earlobes: Free ear lobes (dominant trait) vs. Attached ear lobes (recessive trait)
Free earlobes are those that hang below the point of attachment to the head. Attached
Extra
Glossary
Reference Materials
Student Gallery and Archives
Other Participating Schools
Contact Project Leader
G:.er CIESE Projects
attached directly to the side of the
head.
irrr
r
'l+rrh:1
Forelock: White forelock (dominant trait) vs. No white forelock (recessive trait)
A white forelock is a patch of white hair, usually located at the hairline just above the fore
that shows an example of a white forelock as well as illustrating other easily identified hur
Dimples: Dimples (dominant trait) vs. No dimples (recessive trait)
Dimples are natural dents in the face to the right or left of the mouth.
they should be counted as having dimples.
lf a person has onl
Thumbs; Straight thumb (dominant trait) vs. Curved thumb (recessive
in the illustration below, curved thumbs can be seen as part of a circle.
Pinky: Straight pinky (recessive trait) vs. Bent pinky (dominant trait) Hold your hands togr
covering your face. lf the tips of the pinkies (or baby fingers) point away from one anothe
bent
.
Mid-digit hair: Mid-digit hair (dominant trait) vs. No mid-digit hair (recessive trait) Look for
finger shown by the white arrow below.
rttn://www.ciese ors/curriculum/sennroi f2ltraits.html
312U2009