10
Science
Quarter 3- Module 6
Evidences for Evolution
Source:https://upload.wikimedia.org/wikipedia/common
s/e/eb/Timeline_evolution_of_life.svg
Source:https://www.needpix.com/photo/678237/evolution-skullhead-old-artifact-excavation-bone-skeleton-death
Department of Education ● Republic of the Philippines
Science – Grade 10
Alternative Delivery Mode
Quarter 3 – Module 6: Evidences for Evolution
and Environment
First Edition, 2020
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Members
:
:
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:
:
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Ellen A. Azuelo, PhD, Rejynne Mary L. Ruiz, PhD
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10
Science
Quarter 3- Module 6
Evidences for Evolution
This instructional material was collaboratively developed and
reviewed by educators from public schools. We encourage teachers
and other education stakeholders to email their feedback, comments,
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Department of Education ● Republic of the Philippines
Table of Contents
Cover Page
Copyright Page
Title Page
Table of Contents
Lesson 1: Evidence from Fossil Records
What I Need to Know
What I Know
What’s In
What’s New
What Is It
What’s More
What I Have Learned
What I Can Do
Assessment
Additional Activities
1
1
2
2
3
5
5
6
6
7
Lesson 2: Hint of Evolution from Comparative Anatomy
What I Need to Know
What I Know
What’s In
What’s New
What Is It
What’s More
What I Have Learned
What I Can Do
Assessment
Additional Activities
7
7
8
8
9
10
11
11
12
13
Lesson 3: Evidences from Embryonic Development
What I Need to Know
What I Know
What’s In
What’s New
What Is It
What’s More
What I Have Learned
What I Can Do
Assessment
Additional Activities
13
13
14
14
15
16
17
17
18
18
Post-Test
Answer Key
References
18
20
21
WHAT THIS MODULE IS ABOUT
Introductory Message:
Welcome to the Science 10 Alternative Delivery Mode (ADM) Module on Evidences
for Evolution.
To the Teachers:
This module was collaboratively designed, developed and reviewed by educators
both from public and private institutions to assist you, the teacher or facilitator, in
helping the learners meet the standards set by the K to 12 Curriculum while
overcoming their personal, social, and economic constraints in schooling.
As a facilitator, you are expected to orient the learners on how to use this module.
You also need to keep track of the learners' progress and allow them to manage their
own learning for optimal development and understanding. Furthermore, you are
expected to encourage and assist the learners as they do the tasks included in this
module.
To the Parents:
This module was designed to provide your children with fun and meaningful
opportunities for guided and independent learning at their own pace and time.
As vital partners in education, your support to your children’s learning at home is a
great factor to ensure that they will become successful in what they do. As parents,
you are expected to monitor your children’s progress as they accomplish the tasks
presented in this module and ensure that they will practice learning independently.
To the Learners:
This learning resource hopes to engage you into guided and independent learning
activities at your own pace and time. In other words, your success in completing this
module lies in your own hands. You are capable and empowered to achieve the
competencies and skills presented in this material if you will only learn, create and
accomplish to the best of your ability.
Be rest assured that this material is entirely learner-friendly for this aims to help you
acquire the needed 21st century skills while taking into consideration your needs and
circumstances.
It is our objective, therefore, that you will have fun while going through this module.
Take charge of your learning pace and in no time, you will successfully meet the
targets and objectives set in here which are intended for your ultimate development
as a learner and as a person.
-
From the Science 10 Module Development Team
How to Learn from This Module
To achieve the objectives set in this module, you, the learners, are to do the
following:
•
Take time in reading the lessons thoroughly;

Follow the directions and/or instructions in the activities and exercises
carefully; and
•
Answer all the given tests diligently.
Icons Used in This Module
This module contains the following parts and their corresponding icons:
What I Need to Know
This gives you an idea on what skills or
competencies you are expected to learn in
each lesson.
What I Know
It includes an activity that aims to check your
prior knowledge on the lesson you are about
to take. If you get all the answers correctly
(100%), you may decide to skip the lesson.
What’s In
This serves as a brief drill or review to help
you link the current lesson with that to the
previous one.
What’s New
It offers a new lesson by introducing it
interestingly through a story, a song, a poem,
a problem opener, an activity or a situation.
What Is It
This provides a brief discussion of the lesson.
This aims to help you discover and
understand new concepts and skills.
What’s More
This comprises activities for independent
practice to solidify your understanding and
skills of the topic. You may check the answers
to the exercises using the Answer Key found
at the end of the module.
What I Have Learned
This
includes
questions
or
blank
sentences/paragraphs to be filled in to
process what you have learned from the
lesson.
What I Can Do
It delivers an activity which will help you
transfer your new knowledge or skill into real
life situations or concerns.
Assessment
This aims to evaluate your level of mastery in
achieving the learning competencies.
Additional Activities
This enriches your knowledge or skill of the
lesson learned. It also tends to the retention
of the learned concepts.
Answer Key
This contains all of the answers to all activities
and exercises presented in this module.
At the end of this module, you will also find:
References
This shows the list of all sources used in
developing this module.
Guidelines and Reminders
Before using this module, please take time to read the following guidelines and
reminders:
1. Use the module with care. Do not put unnecessary mark/s on any part of the
module. Use a separate sheet of paper in answering the exercises.
2. Do not forget to answer the What I Know section before moving on to the
other activities included in the module.
3. Read the instructions carefully before doing each task.
4. Observe honesty and integrity in doing the tasks and in checking your
answers.
5. Finish the task at hand before proceeding to the next.
6. Return this module to your teacher/facilitator once you are through with it.
If you encounter any difficulty in answering the tasks in this module, do not
hesitate to consult your teacher or facilitator. Always bear in mind that you are not
alone.
We hope that through this material, you will experience meaningful learning and
be able to gain a deeper understanding of the relevant competencies. You can do
it!
This page is intentionally left blank
Lesson
1
Evidence from Fossil
Records
What I Need to Know
In this lesson, you are going to describe how fossil records can provide
evidences in understanding evolution. It also presents how the age of fossils
is determined through the use of Carbon-14 dating. Furthermore, you would
be able to examine the major events in Earth’s history using the Geologic
Time Scale.
Let us begin!
What I Know
Direction: Choose the CAPITAL LETTER of the best answer. Write the
chosen letter on a separate sheet of paper.
1. A person who studies fossils.
A. Biologist
C. Evolutionist
B. Chemist
D. Paleontologist
2. Where can most of the fossil records be found?
A. Igneous rocks
C. Metamorphic rocks
B. Lava flows
D. Sedimentary rock
3. In what era do the oldest found fossils belong to?
A. Cenozoic
C. Paleozoic
B. Mesozoic
D. Pre-Cambrian
4. This fossil of organisms is traced back to the Cenozoic Era.
A. Crinoid stem
C. Trilobite
B. Man bone
D. Vascular plan
5. This method is used to determine the age of rocks by comparing
them with the other layer.
A. Carbon Dating
C. Relative Dating
B. Radioactive Isotope
D. Rock Formation
1
What’s In
In the previous lesson, you have learned that all organisms possess
unique characteristics. Some organisms may tend to look the same but in
reality, they have distinct differences from each other. Others may not even
be related to one another but they have similar functional features and
characteristics.
Before moving on, take a moment first to answer the question below.
Why are some animals from the past totally different from the animals
that exist at the present?
What’s New
ACTIVITY 1
WHERE DO I BELONG?
Adapted from LM, pp. 304-305
Instructions
1. Analyze the table below.
2. Determine the fossil of organisms recorded in their respective era or
period. Write your answer under the column for Organism. Afterward,
answer the questions that follow.
1. Trilobite
An
invertebrate Era
that lived in a
shallow
marine
environment
during
the
Ordovician
and
Silurian periods.
Cenozoic
Period
Recent
Quaternary
https://www.google.com/search?
q=trilobite&tbm
Tertiary
Crinoids look like
plants but are
actually animals
related to our
modern starfish.
They belong to Mesozoic
Phylum
Echinodermata
2
Cretaceous
Jurassic
Triassic
Organis
m
2. Crinoid Stem
and lived during
the
Triassic
Period.
https://www.google.com/search?
q=crinoid+s
tem&tbm
3. Dinosaur Bones
Dinosaurs
or
giant
reptiles
ruled the Earth
during
the
Jurassic Period
under
the
Mesozoic era.
Paleozoic
Permian
Carboniferous
Devonian
Silurian
Ordovician
https://www.google.com/search?q=dinosaur
+bone+fossil&source=lnms&tbm
4. Vascular Plant
Cambrian
This
fossilized
leaf is once part
of
an
early
vascular
plant
during
the
Carboniferous
Period.
https://www.google.com/search?q=vascular
+plant+fossil&source=lnms&tbm
Guide Questions:
1. Which is assumed to be the oldest organism?
2. In what era can you possibly find the most recent fossil? Why do you say
so?
3. When do you think did the present day humans first appear on earth?
What Is It
Fossil Records
A fossil record is a group of fossils which has been analyzed and
arranged chronologically and taxonomically. Have you ever seen any samples
of fossils belonging to any organism?
Fossils are examples of evidences that paleontologists use in
studying evolution. They are traces of organisms that lived in the past and
3
were preserved by natural process or catastrophic events. They can be the
remains of organisms which can include bones, shells, teeth and also feces
embedded in rocks, peat, resin, and ice. A paleontologist is a person who
studies fossils. In the studies of paleontologists, they have found that most
fossils are commonly found in sedimentary rocks. They were from the hard
parts of the organisms like woody stem, bones or teeth.
Another type of fossil is an imprint or impression. Imprints are
shallow external molds left by animal or plant tissues with little or no organic
materials present.
Paleontologists make initial estimates of the age of fossils through the
position of the sedimentary rocks. Although generally, fossils that are found in
the bottom layer are much older than those found in the upper layer of the
rocks.
Methods Used in Determining the Age of Fossils
Experts make use of several methods to determine the age of fossils.
These methods are the following:
1. Relative Dating - This method is used to determine the age of rocks by
comparing them with the rocks present in the other layer. The younger
sedimentary rock layer is assumed to be found on top and the older
rock is found at the bottom layer.
2. Radiometric Dating - This type of
dating is used to determine the
age of rocks using the decay
of radioactive isotopes present
among the rocks such as
Carbon-14. All organisms have
decaying Carbon-14 in them.
Plants and animals that are still
alive constantly replace the
supply of carbon in their body
while the amount of carbon-14
https://www.pinterest.ph/pin/452400725045912231/
in their body stays the same. When an organism dies, carbon-14 will
start to decay.
3. Carbon Dating- It is used to tell the age of organic materials. Art
collectors use carbon dating to determine if a piece of artwork is
genuine or not.
Geologic Time Scale
Out of the examinations of layers of rocks and dating of fossils,
scientists were able to develop the Geologic Time Scale. This scale shows
the major events in the Earth’s history. It also shows the appearance of
various kinds of organisms in a particular period of time on Earth.
Era, the largest division of the Geologic Time Scale, has the following
parts: Precambrian, Paleozoic, Mesozoic, and Cenozoic. Each era is further
divided into periods.
Do you want to know how to determine the age of a fossil? If you do,
then try the next activity.
4
What’s More
ACTIVITY 2
WHAT’S MY AGE?
Adapted from LM, pp. 306-307
Instruction:
Use the information below to determine the age of the fossils.
One way scientists determine the age of fossils is by checking the amount of
radioactive carbon-14 in the fossil. Carbon-14 breaks down or decays to form
Nitrogen-14 and the rate of this decay is constant. For instance, half of the remaining
carbon-14 breaks down every 5, 730 years.
Use this information to compute the age of fossils below.
1. Trilobite
Age of Fossil
(in years)
______5730______
________
_
2. Dinosaur bones
___5730________5730______
__
3. Crinoid stem
_5730_
___5730__ ______5730______
__
________
_
________
_
Guide Questions:
1. What is the oldest fossil?
2. How long does it take for half of the carbon-14 to break down or decay?
What I Have Learned
Check your understanding! Write your answers on your notebook.
1. Why is it important to know the age of a fossil?
2. What is the Geologic Time Scale? What does it do?
5
What I Can Do
Apply what you have learned!
GEOLOGIC TIMELINE ACTIVITY
Significant developments and the extinction of plant and animal life can
be shown in a Geologic Time Scale.
Materials
calculator, activity notebook
Instruction
1. Complete the table below to show how long each era has lasted.
The Divisions of Geologic Time
Percent
Millions of Years (my)
The age of the Earth
100%
4,600 my
Cenozoic Era
1.5%
Mesozoic Era
4.0%
Paleozoic Era
6.5%
Precambrian Era
88.0%
2. Create a pie chart showing the percentage of how each era of geologic time
is being represented in the Geologic Time Scale.
Assessment
Direction: Choose the CAPITAL LETTER of the best answer. Write
the chosen letter on a separate sheet of paper.
1. Where can most of the fossil remains be found?
A. Igneous rocks
C. Metamorphic rocks
B. Lava flows
D. Sedimentary rocks
2. A person who studies fossils.
A. Biologist
C. Evolutionist
B. Chemist
D. Paleontologist
3. This method is used to determine the age of rocks by comparing
the rocks from those found in the other layer.
A. Carbon Dating
C. Relative Dating
B. Radioactive Isotope
D. Rock Formation
4. This fossil of organisms is traced back to the Cenozoic Era.
A. Crinoid stem
C. Trilobite
B. Man Bone
D. Vascular plant
5. In what era do the oldest found fossils belong to?
A. Cenozoic
C. Paleozoic
B. Mesozoic
D. Pre-Cambrian
6
Additional Activities
GEOLOGIC TIME SCALE CHALLENGE!
You are challenged to provide a different way on how to present the
Geologic Time Scale aside from the pie chart that you have just made in the
previous activity. Let us say that the scale can be represented using a bar
graph, a layered cake or a flight of stairs.
This time, you are encouraged to make a model of the Geologic Time
Scale based on your own image or analogy. Be creative and innovative!
Lesson
2
Hint of Evolution
from Comparative
Anatomy
What I Need to Know
In this lesson, you are going to describe how comparative anatomy is
used by experts when tackling evolution. It is also in this lesson that you are
expected to distinguish the different species, specifically on whether they are
homologous or analogous in terms of their structures.
So, gear up and prepare to explore!
What I Know
TRUE OR FALSE
Direction: Write the word True if the statement is correct and False if not.
1. The study of the differences and similarities present among different things
is called comparative anatomy.
2. A homologous structure means that a structure is anatomically the same
but functionally different.
7
3. The wing of a bat and a human arm is a pair showing an analogous
structure.
4. Analogous structure is also called divergent evolution.
5. In convergent evolution, organisms that are closely related develop similar
characteristics due to them living in a similar environment.
What’s In
In the previous lesson, you have discovered that fossil records do
provide sources of evidence for evolution which gave way to the concept
about the origin of life.
You have also learned that fossil records can tell the history of life,
which are the remains or imprints of organisms from earlier geological periods
that were preserved in sedimentary rocks.
The Geologic Time Scale was also mentioned. Now try to answer this
first. Why is this scale very significant in the study of evolution?
At this point, perform the next activity for you to gain a deeper
understanding on the anatomical structures and functions of different
organisms.
ACTIVITY 3
AHA! ANALOGOUS! HOMOLOGOUS!
What’s New
Adapted from LM, pp. 310-311
Instruction: In the space provided, write H if the structures specified are
homologous and A if they are analogous. Follow-up questions
are also prepared for you to answer.
Structure
1. Human Arm
Whale Flipper
https://www.google.com/search?q=
human+arm+anatomy&tbm
https://www.google.com/search?
q=flipper+whale+anatomy&tbme Flipper
8
Classification
2. Human Arm
Alligator
https://www.google.com/search?q=
human+arm+anatomy&tbm
forelim
bhttps:
//www.google.com/
search?q=alligator+forelimb+anatomy&tbm
3. Bat Wing
Butterfly Wing
https://www.google.com/search?
q=butterfly+wing+anatomy&tbm
https://www.google.com/search?
q=bat+wing+anatomy&tbm
4. Bird Wing
Butterfly Wing
https://www.google.com/search?
q=bird+wing+anatomy&tbm
https://www.google.com/search?
q=butterfly+wing+anatomy&tbm
Guide Questions:
1. Can you say that humans, whales and bats could possibly belong to a
common ancestral group? Explain why.
2. Give other examples of homologous structures.
What Is It
Hint of Evolution from Comparative
Anatomy
Another hint of evolutionary concept
is
from
comparative
anatomy.
Comparative anatomy is the study of the
similarities and differences present in the
anatomy of various species. It is an
important tool that helps to determine the
9
evolutionary relationships between organisms and whether or not they
share common ancestors. Meanwhile, anatomical similarities between
organisms support the idea that these organisms evolved from a common
ancestor.
When referring to anatomical structures, they can either be
homologous or analogous.
1. Homologous structures These refer to structures from different species
which have similar internal framework, position, and embryonic development.
Homologous structures may have the same origin or ancestors but different
functions. This type of evolution is called divergent evolution. Divergent
evolution is the splitting of an ancestral population into two or more subpopulations that are geographically isolated from one another. The following
is an example of a homologous structure: The forelimbs belonging to a dog,
man, cat, bat, bird, lizard, and whale are structurally the same, but are
functionally different.
2. Analogous structures – The structures of unrelated species may evolve
for them to look somewhat the same because the structure has adapted to
similar functions. In another words, analogous structures have similar
functions but different in origin. In convergent evolution, analogous
structures of unrelated organisms from different ancestors developed a similar
function. This is one example: The wings of birds, bats, and insects exhibit the
same functions.
At this time, do the activity below to have a better grasp on
comparative anatomy.
What’s More
ACTIVITY 6
SEE THE DIFFERENCE!
Instruction: Supply the missing data in the table to show the comparison
between homologous and analogous structures.
Comparison between Homologous and Analogous Structures
Basis of Comparison
Homologous Structure
Origin
Function
Example
10
Analogous Structure
What I Have Learned
Answer the questions concisely.
1. What is the importance of comparative anatomy in the study of evolution?
2. What is the difference between homologous and analogous structures?
What I Can Do
ARTWORK ACTIVITY
The picture below shows the forelimbs of six organisms that depict
homologous structures. For this activity, you are going to draw the forelimbs
of the six organisms.
Use a legal size bond paper as your canvass then use coloring
materials to add beauty to your artwork.
Source: https://sites.google.com/a/hcpss.me/hahs_ferraro_biology/quarter-4-links/evolution-activity/station-2-comparative-anatomy---homologous-structures
RUBRICS FOR DRAWING
ADAPTED: Rcampus
https://www.rcampus.com/rubricshowc.cfm?sp=yes&code=N7A24B&
Craftsmanship
5 pts
Emerging
1 pt
Competent
2 pts
Art work is messy and
shows smudge marks
and rips, tears, or folds.
Erasure lines showing.
Art work is
somewhat messy
and shows either
smudge marks or
rips, tears, or
11
Proficient
3 pts
Distinguished
4 pts
Art work is neat and Art work is
shows very little
impeccable and
evidence of
shows no
smudge marks,
evidence of smudge
rips, tears, or folds. marks, rips, tears, or
folds.
Some erasure
lines showing.
A few erasure lines folds. No erasure
showing.
lines showing.
Art work shows
good technique. All
objects are placed
in correct space.
Negative and
positive space is
almost balanced.
Technique/
Art Concepts
5 pts
Art work lacks
technique and/or
understanding of art
concepts.
Art work shows
some technique
and
understanding of
art concepts.
Creativity
5 pts
Art work shows little or
no evidence of original
thought. Student does
not use line, shading or
form in a creative
manner.
Art work shows Art work reflects
some evidence of originality.
originality.
Student uses line,
Student uses line, shading or form in
shading or form in an original manner.
a slightly original
manner.
Art work reflects a
high level of
originality.
Student uses line,
shading or form in a
highly original
manner.
Shading/
Proportion
5 pts
Completed art work is
not shaded or
incorrectly shaded. Still
life objects are incorrect
in
proportion with real life
objects.
Completed art
work is half
shaded showing
average
placement of light
and darks using
average drawing
technique. Some
still life objects
are in proportion
with real life
objects.
Completed art work
is fully shaded
showing excellent
placement of light
and darks using
excellent drawing
technique. Still life
objects are in
excellent
proportion with real
life objects.
Completed art work
is almost fully
shaded showing
good placement of
light and darks
using good drawing
technique. Still life
objects are mostly
in good
proportion with real
life objects.
Art work shows a
mastery of
advanced
techniques in
composition. All
objects are placed in
correct space.
Negative and
positive space is
balanced.
Assessment
TRUE OR FALSE
Instruction: Write the word True if the statement is correct and False if not.
1. In convergent evolution, organisms that are closely related develop similar
characteristics due to them living in a similar environment.
2. The study of the differences and similarities among different things is called
comparative anatomy.
3. If you compare the wing of a bat and a human arm, you would have an
example of an analogous structure.
4. Analogous structure is also called divergent evolution.
5. Homologous structures are anatomically similar in structure but different in
function.
12
Additional Activities
Do A Research
For this activity, you will study homologous and analogous structures.
You will make observations and analyze your data to determine which
structures can be used to imply evolutionary relationships and which cannot.
Specifically, you will study the bones in the upper limbs of whales, humans,
cats and dogs and also the function of the upper limbs among birds, insects
and bats.
Lesson
3
Evidence from
Embryonic
Development
What I Need to Know
In this lesson, you are going to describe how embryonic development
can shed some light in the study of evolution and on how the amino acid
sequence found within the DNA of organisms can help trace their
relationships with one another.
What I Know
TRUE OR FALSE
Direction: Write the word True if the statement is correct and False if not.
1. Based on their amino acid sequences, human beings and wheat are least
related from each other.
2. According to evolutionists, the best test that can be performed to show the
relatedness of two organisms is by examining the similarities in their
genomic DNA.
3. The embryonic development of birds and humans show similarities in
stage 1.
4. An embryo is an early stage of development among organisms.
5. Gorillas and humans have a common ancestry as seen in their amino acid
sequence.
13
What’s In
In the previous lesson, you were informed that when trying to dig
deeper into the study of evolution, one can look into comparative anatomy as
one of the concepts that can explain the origin of life. Also, two important
terms, homologous and analogous, which pertain to the structures of different
species were also introduced and discussed.
Before unveiling the next topic, take time to answer first this question.
How do you distinguish a homologous structure from an analogous structure?
What’s New
ACTIVITY 5
SO, WHO IS MY RELATIVE?
Adapted from LM, pp. 311-312
Direction: Study and compare the stages of the embryonic development of
some vertebrates. Write your answers on your activity notebook. For
your reference, please refer to the figure found in the succeeding page.
Guide Questions
1. In what stages of development did the organisms start to show some
similarities?
2. In the third stage, identify the structure that made the organisms different
from one other.
3. Can embryonic development be a basis for evidence to prove that evolution
has indeed taken place?
Stages of the Embryonic
Development of Different
Vertebrates
Source: Carale (1989)
14
What Is It
Evidence from Embryonic Development
Embryology is the study of the anatomy development of an organism
to its adult form. It provides evidence for evolution as embryo formation in
widely-divergent group of organisms tends to be well conserved. That is to
say, structures that are absent among adults of some groups often appear
during their embryonic forms.
An embryo is an early stage of development among organisms. As
such, embryonic development includes stages such as blastula, gastrula, and
organogenesis. The embryo of fishes, salamanders, lizards, birds, cats, and
humans are similar during the first stage of their embryonic development.
However, they have several homologous structures that are no longer present
when they become adults. Due to these manifestations, embryonic
development is considered to be very useful when studying the relationship of
organisms.
Studies have also shown that closely-related species can exhibit
similar embryonic development but their adult structures can become quite
different later on.
Amino Acid Sequence
Another evidence for evolution is provided by the biochemical analysis
and amino acids sequence of an organism’s DNA. For example, it is clear that
the evolution of the new functions of proteins commonly occurs after gene
duplications. These types of duplication allow the free modification of one
copy by mutation, selection, or drift (changes in a population’s gene pool
resulting from chance), while the second copy continues to produce a
functional protein.
This means that the greater the similarity present in the amino acid
sequence, the closer the relationship is among the organisms. Also,
organisms with similar structures and biochemical compositions could have
probably descended from a common ancestor.
To increase your understanding on amino acid sequences and their
determining factor to the relationship of organisms, perform the activity in the
next section.
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What’s More
ACTIVITY 6
LET’S COMPARE
Procedure
1. Given below are the amino acid sequences found in the cytochrome C of a
human, chimpanzee, gorilla, Rhesus monkey, horse, and kangaroo.
Cytochrome C is a respiratory enzyme located inside the mitochondria.
2. First, study carefully these sequences.
3. Next, supply the missing amino acid sequence of the chimpanzee, gorilla,
Rhesus monkey, horse, and kangaroo to complete Tables 2, 3, and 4.
Refer to Table 1 for your answers.
4. Afterward, identify the differences of the amino acid sequences among
these organisms. Use the human’s amino acid sequence as your
reference.
5. Finally, complete Table 5 to show the differences in the number of amino
acids and the positions in which they vary.
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Guide Questions
1. Based on the activity, which of the organisms is the most closely related to
humans?
2. Which is the least related to humans?
3. If the amino acid sequences of two organisms are similar, would it mean
that their DNA would also be similar? Explain your answer.
What I Have Learned
1. What is embryonic development?
2. How does embryonic development provide evidence for evolution?
What I Can Do
Apply what you have learned!
Study this statement: “The greater the similarity in amino acid sequence, the
closer the relationship is of the organisms.”
Answer this briefly: What is your opinion on the claim that gorillas and humans
have a common ancestry? Explain your answer.
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Assessment
TRUE OR FALSE
Direction: Write the word True if the statement is correct and False if not.
1. Based on their amino acid sequences, humans and wheat are least related
from each other.
2. According to evolutionists, the best test that can be performed to show the
relatedness of two organisms is by checking for the similarity in their
genomic DNA.
3. Embryonic development of birds and humans show similarities in
stage 1.
4. An embryo is an early stage of development in organisms.
5. Gorillas and humans have a common ancestry based on their amino
acid sequences.
Additional Activities
Exit Slip
Using the evidences cited from the previous activities, construct an
explanation to show how comparative embryology can be used as an
evidence for the theory of evolution.
A.
B.
C.
D.
Claim
Evidence
Reason
Conclusion
Post - Test
Direction: Choose the CAPITAL LETTER of the best answer.
1. Which pair of animals shows a correct example of homologous
structures?
A. Wings of a butterfly and a bat
B. Flipper of a whale and forelimb of a cat
C. Fingers of a human and arm of a starfish
D. Tongue of a frog and proboscis of a mosquito
2. Where can most of the fossil remains be found?
A. Black soil
C. Lava flows
B. Granite rock
D. Sedimentary rocks
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3. Which of the following statements DOES NOT describe evolution?
A. Evolution is continuous.
B. Evolution refers to change.
C. If there is mutation, there is change.
D. The world is stable and unchanging.
4. In what era do the oldest found fossils belong to?
A. Cenozoic
C. Paleozoic
B. Mesozoic
D. Pre-Cambrian
5. Which definite characteristic shows the relatedness of two organisms?
A. Similarity in development
C. Similarity in structure
B. Similarity in courting structure
D. Similarity in genomic DNA
6. Why do geologists use the Geologic Time Scale?
A. Due to the leap year
B. Due to time responsibility
C. Due to the vegetation of the Earth
D. Due to the time span of the Earth’s history
7. What is comparative anatomy?
A. The study of intermediate fossils.
B. The study of the development of a zygote to a newly born organism.
C. The study of the similarities in the anatomical structures of different
species.
D. The study of the functions of the anatomical structures within
species.
8. It is a record of the geologic events and the evolution of life forms as
shown in the fossil records.
A. Evolution Book
C. Geologic Time Scale
B. Fossil recording
D. Relative Dating
9. What is the oldest period in the Geologic Time Scale?
A. Cambrian
C. Pre-Cambrian
B. Cretaceous
D. Silurian
10. It is subdivided into units of geologic time called periods.
A. Century
C. Period
B. Era
D. Year
11. What is a homologous structure?
A. An anatomical structure that no longer serves a purpose in one
specie.
B. An anatomical structure that serves a similar purpose between two
unrelated species.
C. An anatomical structure that is shared between two species with a
common ancestor.
D. All of these describe a homologous structure.
12. It is a preserved remain of ancient organisms.
A. Embryo
C. Fossil
B. Evolution
D. Vestigial structure
13. The study of embryos and their development.
A. Biology
C. Evolution
B. Embryology
D. Paleontology
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14. The process by which modern organisms have descended from
ancient organisms over time.
A. Analogous
C. Fossil
B. Evolution
D. Homologous
15. Evidences for evolution can be traced from the fossils recorded, and
from the structural and embryological development of
organisms.
A. False
B. True
Answer Key
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References
Books:
Science 10 Learner’s Material pages 302-316
Online Websites:
Evidence from Fossil Records
https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Book
%3A_General_Biology_(Boundless)/18%3A_Evolution_and_the_Origin_of_S
pecies/18.5%3A_Evidence_of_Evolution/18.5A%3A_The_Fossil_Record_as_
Evidence_for_Evolution
https://www.svsd410.org/cms/lib05/WA01919490/Centricity/Domain/1355/We
ek%206-%20Geological%20Time%20Scale.pdf
https://quizlet.com/69526395/lesson-4-the-geologic-time-scale-flash-cards/
https://www.cpalms.org/Public/PreviewResourceLesson/Preview/43470
Comparative Anatomy
https://en.wikipedia.org/wiki/Comparative_anatomy
https://www.teacherspayteachers.com/Product/MS-LS4-2-ComparativeAnatomy-Lab-Stations-Activity-3626608
https://sites.google.com/a/hcpss.me/hahs_ferraro_biology/quarter-4links/evolution-activity/station-2-comparative-anatomy---homologousstructures
Embryonic Development
https://bio.libretexts.org/Bookshelves/Microbiology/Book%3A_Microbiology_(B
oundless)/8%3A_Microbial_Evolution%2C_Phylogeny%2C_and_Diversity/8.0
1%3A_Origins_of_Life/8.1A%3A_Evidence_of_Evolution
https://www.slideshare.net/daniholic/science-10-learners-material-unit-3
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