Name: Date:
Student Exploration: Embryo Development
Vocabulary: Blastula, Carnegie stages, differentiation, ectoderm, embryo,
embryology, embryonic stem cells, endoderm, fetus, gastrula, inner cell mass,
mesoderm, morula, neurula, primitive streak, trilaminar disk, zygote
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. The images below show embryos of different species at different stages of
development. Label the images below with 1-4 from least developed to most
developed.
A B C D
2. Which image above do you think is a human? Explain.
Gizmo Warm-up
Embryology is the study of the development of embryos from a single cell to a multicellular
fetus. In the Embryo Development Gizmo, you will compare the development of different
animals and learn the details of mammalian development. To begin, be sure the COMPARE tab
is selected.
1. What do the images have in common?
Click on the check box to turn on Scale bars and labels. You are observing the
zygotes, or fertilized single cells, of five animals.
2. At this point, are you able to tell which animal is which?
Explain.
, Get the Gizmo ready:
Activity A:
Make sure the COMPARE tab is selected and
Comparative
the
embryology
Developmental stage slider is on stage 1.
Turn off Scale bars and labels.
Introduction: Comparative embryology compares embryos of different species to
gain insight into how they are related. To provide a framework for this comparison,
embryologists divide this process into 23 Carnegie stages. You will look at seven of
these stages in this activity.
Question: Can we use comparative embryology to determine the relatedness of species?
1. Challenge: Drag the labels to the embryos you think they belong to. Fill in the
first row of the table below with your guesses. Then, move the Developmental
stage slider one position to the right, to Carnegie stage 4. Rearrange your labels
if necessary and fill in the next row of the table. Continue until you get to stage
23. Don’t turn on the Reveal answers check box until the end. (Note: Your
guesses may change as you go through the stages. Don’t worry, they won’t be
graded - this is just for fun!)
Stage A B C D E
1
4
8
13
16
20
23
2. Reveal: Click Reveal answers.
A. Did you guess correctly in the end?
B. At which stage were you able to tell which was which?
Explain:
3. Observe: Drag the Developmental stage slider back to stage 8. Turn on Scale bars
and
labels. What structure does all of the embryos have in common?
The neural groove will fold into a neural tube and will become the central nervous
Student Exploration: Embryo Development
Vocabulary: Blastula, Carnegie stages, differentiation, ectoderm, embryo,
embryology, embryonic stem cells, endoderm, fetus, gastrula, inner cell mass,
mesoderm, morula, neurula, primitive streak, trilaminar disk, zygote
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. The images below show embryos of different species at different stages of
development. Label the images below with 1-4 from least developed to most
developed.
A B C D
2. Which image above do you think is a human? Explain.
Gizmo Warm-up
Embryology is the study of the development of embryos from a single cell to a multicellular
fetus. In the Embryo Development Gizmo, you will compare the development of different
animals and learn the details of mammalian development. To begin, be sure the COMPARE tab
is selected.
1. What do the images have in common?
Click on the check box to turn on Scale bars and labels. You are observing the
zygotes, or fertilized single cells, of five animals.
2. At this point, are you able to tell which animal is which?
Explain.
, Get the Gizmo ready:
Activity A:
Make sure the COMPARE tab is selected and
Comparative
the
embryology
Developmental stage slider is on stage 1.
Turn off Scale bars and labels.
Introduction: Comparative embryology compares embryos of different species to
gain insight into how they are related. To provide a framework for this comparison,
embryologists divide this process into 23 Carnegie stages. You will look at seven of
these stages in this activity.
Question: Can we use comparative embryology to determine the relatedness of species?
1. Challenge: Drag the labels to the embryos you think they belong to. Fill in the
first row of the table below with your guesses. Then, move the Developmental
stage slider one position to the right, to Carnegie stage 4. Rearrange your labels
if necessary and fill in the next row of the table. Continue until you get to stage
23. Don’t turn on the Reveal answers check box until the end. (Note: Your
guesses may change as you go through the stages. Don’t worry, they won’t be
graded - this is just for fun!)
Stage A B C D E
1
4
8
13
16
20
23
2. Reveal: Click Reveal answers.
A. Did you guess correctly in the end?
B. At which stage were you able to tell which was which?
Explain:
3. Observe: Drag the Developmental stage slider back to stage 8. Turn on Scale bars
and
labels. What structure does all of the embryos have in common?
The neural groove will fold into a neural tube and will become the central nervous
