EMBRYONIC DEVELOPMENT

2.  Explain what embryonic development is.
 Explain how embryonic development provides
clues for evolution.
 Compare the stages of embryonic development
of different organisms through an activity.
 Illustrate the embryonic process through a cycle
diagram.

3.  How fossil records and comparative
anatomy are used as evidence of
evolution?
 Distinguish homologous structure from
the analogous structure.

4. • As the organisms grow and develop, the
embryos gradually become more and
more dissimilar. These differences in form
are caused by genes that were turned on
in the process of development through
time.

5. • Differences in the form are controlled by the
genetic blueprint of the organisms; and
mutations in some of these genes may lead to
congenital defects, physical abnormalities,
cancer, and predisposition to infection. Yet on
some very rare occasions minor mutations
promote desired trait for growth or resistance
to disease.

6. “How did life begin and evolve on
the planet Earth?”
How did life on Earth change
through time?

7. Changes in the earth's environment have
facilitated
the changing the lives on earth. From the
time of the origin of life on earth has
changed in many ways. The Earth has
also changed from the time of its origin.
Both live on earth itself are dynamic.

8. How many life forms are there
on Earth?

9. -Humans share the planet with
as many as 8.7 million
different forms of life, according
to what is being billed
as the most accurate estimate
yet of life on Earth.

10. Activity 1:
The students are asked to arrange the
pictures based on the stages of the
developmental stages of the organism.
Developmental Stages of a Butterfly

11. Guide Questions:
1. What are the 4 stages of a monarch
butterfly?
2. How long does it take for a caterpillar to
become a butterfly?

12. Guide Questions:
1. What are the 4 stages of a monarch
butterfly?
2. How long does it take for a caterpillar to
become a butterfly?

13. • The four stages of the lifethe larvae (caterpillar), the pupa
(chrysalis), adult emergence cycle of the monarch butterfly
life cycle are: the egg,, and the adult butterfly.
• The process from egg to butterfly is weather dependent
and also depends on the regional climate. It can take about
four weeks at the peak of the summer in warmer climates.
The egg takes 5 to 10 days, the larva/caterpillar and
pupa/chrysalis each take about 10 to 14 days.
Stages of the life cycle of the monarch butterfly

14. • Who is your relative?
• Why is it important to know
your relatives?

15. Activity 2: So, who is my relative?

16. Guide Questions:
1. In what stages of development of the
organisms show similarities?
2. Identify the structure, how, and where
are they similar?
3. In stage 3, what are the structures that
made the organisms differ from each
other?

17. 4. Can embryonic development be a
piece of evidence that evolution take
place?

18. Answer to Analysis:
1. The first and second stages of
development of the organisms show
better similarities.
2. The shape of the head, lower parts of
the body, and forelimbs.
3. Organisms are different in size, shape of
the head, hind limbs, forelimbs, structure
of the eyes, etc.

19. 4. Similarity in structures may suggest
that organisms share common ancestors.

20. •Embryonic development is the process by which
the embryo forms and develop.
•Development changes here meant the series of
changes in body structure that an animal goes
through from egg to adult.

21. •A lizard, chicken, and man look very different in
appearance. However, their embryos go through
similar development changes.
• The three organisms (reptile,bird, and man) are all
classified as chordates, specifically
vertebrates. Their development is very different from
that of the fly and grasshopper which are classified as
insects.

22. •Scientists believe that organisms that undergo
similar development changes have close
evolution.