Embryogenesis and Development Flashcards
List the 5 steps of embryogenesis
- ) Fertilization
- ) Morula
- ) Blastula
- ) Gastrulation
- ) Neurulation
Describe the process of fertilization.
Occurs in the Ampulla of fallopian tube.
Sperm’s Acrosomal enzymes penetrate
corona radiate & zona pellucia.
Acrosomal enzymes inject pronucleus.
Cortical reaction releases Ca2+ which
depolarizes ovum membrane and makes
it impenetrable.
What is the morula?
Early, solid mass of cells`
Where does the blastula implant?
- Implants in endometrial lining
- Fluid filled blastocoel
- Trophoblast –> Chorion / placenta
- Inner Cell Mass –> Organism
When does the ectoderm, mesoderm and endoderm develop?
Gastrulation
Ectoderm:
Nervous system, skin, hair, nails, mouth, anus.
“Atract-oderm”: Skin, hair are things people are attracted to.
Mesoderm:
Muscoskeleton, circulatory system, gonads, adrenal cortex.
“Move-oderm”: Involved in moving things such as muscles, RBC, steroids
Endoderm
Endocrine glands, GI tract, respiratory tract, bronchi, bladder, stomach.
“In-doderm”: Things that are inside.
Describe the process of neurulation
Mesoderm develops a Notochord. Notochord induces Ectoderm.
Ectoderm –> Neural folds ——-> Neural tube-→ central nervous system
Ectoderm-→ Neural folds -→ Neural Crest cells -→ Peripheral nervous system
What are totipotent stems cells?
Totipotent: “Total”, can be any type of cell
What are pluripotent stem cells?
Pluripotent: Can be any cell except those found in placental structures
Multipotent stem cells
Multipotent: More specialized. Can be multiple types of cells
How is fetal hemoglobin different then adult hemoglobin?
Fetal Hemoglobin (HbF): higher O2 affinity than HbA O2 and CO2 exchange via diffusion
Define determination in terms of cell specialization.
Cell commits to becoming a certain type of cell
Define differentiation in terms of cell specialization
Follows determination. Selectively transcribe genes appropriate for cell’s specific function
