Laboratory Exercise 1 – Development
Biology 3426 / University of Puerto Rico at Aguadilla / Spring 2010 / RJMAYER
In this exercise we will become familiarized with the basic embryological structures of
animals by looking at a set of prepared slides of embryos from three main groups of
animals (Echinoderms, Amphibians and Birds) at different stages of development.
Note the differences and similarities in the early developmental stages of these animals.
Drawings will not be required for this exercise due to the large number of slides that you
need to view. BUT MAKE SURE YOU CAN RECOGNIZE THEM IN A PRACTICAL
EXAM.
Taking pictures carefully (without scratching) ocular lenses of microscopes is permited.
MAKE A COPY OF THIS LIST AND BRING IT TO THE LAB. NO COPIES WILL BE
AVAILABLE
Slides and structures that you are responsible for identifying:
** c.s. = cross section; w.m. = whole mount; sag.sec. = sagital section **
I. Starfish development
1. Starfish unfertilized – w.m. (1 slide available!!!)
a. Nucleus
b. Nucleolus
c. Cell membrane
2. Starfish fertilized polar bodies – w.m. (2 slides available)
3. Starfish early cleavage – w.m. (4 slides available)
4. Starfish late cleavage – w.m. (6 slides available)
5. Starfish 2 cells – w.m. (1 slide available!!!)
a. Fertilization membrane
6. Starfish 4 cells – w.m. (2 slides available)
7. Starfish 8 cells – w.m. (1 slide available!!!))
8. Starfish 16 cells – w.m. (1 slide available!!!)
9. Starfish 32 cells – w.m. (1 slide available!!!)
10. Starfish 64 cells – w.m. (1 slide available!!!)
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DEVELOPMENT LAB 1
11. Starfish blastula – w.m. (2 slides available)
a. Blastocoel
12. Starfish early gastrula – w.m. (4 slides available)
a. Blastopore
b. Archenteron
c. Blastocoel
d. Invagination
e. Identify part that will become ectoderm
f. Identify part the will become endoderm
13. Starfish mid gastrula - w.m. (4 slides available)
14. Starfish late gastrula - w.m. (4 slides available)
a. Coelomic sacs
b. Identify part that will become coelom
c. Identify the part that will become the mesoderm
15. Starfish early bipinnaria - w.m. (5 slides available)
a. Anus
b. Coelomic pouch
c. Mouth
d. Stomach
16. Starfish late bipinnaria - w.m. (4 slides available)
** Note the symmetry of the larvae **
II. Frogs
1. Frog blastula - typ.sag.sec H&E (2 slides available)
2. Frog crescent blastopore – sec H&E (5 slides available)
3. Frog early cleavage – typ.sag.sec H&E (4 slides available)
4. Frog late cleavage – typ.sag.sec H&E (4 slides available)
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DEVELOPMENT LAB 1
III. Chicken embryo
1. Chicken embryo - rep. c.s. (24 hours) (5 slides available)
a. Neural tube
b. Neural folds
c. Neural groove
d. Head fold
e. Margin of amnion
f. Notochord
g. Somites
h. Surface ectoderm
i. Vascularized area
j. Primitive streak
2. Chicken embryo - c.s. (48 hours) (10 slides available)
* These are multiple cross sections of the embryo placed on the slide
a. Metencephalon
b. Ear
c. Myencephalon
e. Mesencephalon
f. Diencephalon
g. Eye
h. Telencephalon
i. Heart
j. Posterior margin of amnion
k. Somites
l. Neural tube
m. Caudal fold
3. Chicken embryo - w.m. (72 hours) (5 slides available)
* Be careful not to damage slide while focusing!!
a. Otic vesicle
b. Aortic arches
c. Nasal pit
d. Eye
e. Brain
f. Vitelline vein
g. Limb bud
h. Vitelline artery
i. Vitelline vein
4. Chicken - c.c. (72 hours) (only one slide available)
Try to identify the same structures listed for the previous slide
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DEVELOPMENT LAB 1
IV. Sperm Cells
* Compare the form and structure of sperm cells from different species of animals.
1. Starfish sperm (3 slides available)
2. Bull sperm smear (4 slides available)
3. Frog sperm flagella (4 slides available)
4. Chicken sperm smear (4 slides available)
5. Sperm smear rat (4 slides available)
6. Sperm smear human (2 slides available)
NOTES:
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DEVELOPMENT LAB 1