Embryology PicsBiology 6 Practical Exam

Sea Urchin Cleavage

Zygote 2 celled 4 celled 8 celled

http://www.vcbio.science.ru.nl/en/virtuallessons/embryology/seaurchinstage/

Sea Urchin Morula

http://www.vcbio.science.ru.nl/en/virtuallessons/embryology/seaurchinstage/

blastomeres

Sea Urchin Blastula

Sea Urchin Gastrula

Frog – Early Blastula

Frog Blastula

(future)(future)

Frog Blastula

1. area of mitosis2. blastocoel3. cortical layer4. cortical layer5. area of invagination (opposite area of sperm entrance

A = anteriorP = posterior

http://discoverdevelopment.com/php/slidesfrogearlydev.php

Frog – Early Gastrulayolk plug

Ventral

Dorsal

Archenteron

endoderm

ectoderm

Frog – Late Gastrula1. Ectoderm2. Endoderm3. Mesoderm4. Blastocoel5. Archenteron6. Dorsal lip of blastopore7. Blastopore8. Ventral lip of blastopore9. Yolk plug

A = anteriorP = posterior

http://discoverdevelopment.com/php/slidesfrogearlydev.php

Frog Neurula

Frog Neurula

1. Neural folds2. Neural crest cells3. Ectoderm4. Endoderm5. Ventral mesoderm/lateral plate mesoderm6. Notochord7. Dorsal mesoderm/paraxial mesoderm8. Archenteron

Starfish Development

4 celled 8 celled Blastula

Early gastrula Late Gastrula