Embryonic stem cells | Cells | MCAT | Khan Academy

TL;DR

The process of fertilized egg development into a blastocyst involves cleavage, differentiation of outer cells (trophoblasts) and inner cells (embryoblast), and the potential use of embryonic stem cells for medical purposes.

Transcript

Where we left off after the meiosis videos is that we had two gametes. We had a sperm and an egg. Let me draw the sperm. So you had the sperm and then you had an egg. Maybe I'll do the egg in a different color. That's the egg, and we all know how this story goes. The sperm fertilizes the egg. And a whole cascade of events start occurring. The walls... Read More

Key Insights

• 💁 Fertilization results in the formation of a diploid zygote.
• 🥺 Cleavage leads to the formation of a morula, which resembles a mulberry.
• ❓ The morula eventually develops into a blastocyst with trophoblast and embryoblast cells.
• 😒 Embryonic stem cells have the potential to differentiate into any cell type and have sparked debates regarding their use due to the destruction of embryos.

Questions & Answers

Q: What happens after fertilization?

After fertilization, the zygote undergoes cleavage, which involves mitosis and splitting into multiple cells.

Q: How does the zygote develop into a blastocyst?

The mass of cells formed during cleavage is called a morula, which differentiates into outer trophoblast cells and inner embryoblast cells, eventually forming a blastocyst.

Q: What are embryoblast cells?

Embryoblast cells are the inner cells of the blastocyst that have the potential to turn into any cell type in the human body.

Q: What are trophoblast cells?

Trophoblast cells are the outer cells of the blastocyst that contribute to the formation of the placenta in mammals.

Summary & Key Takeaways

• After fertilization, a zygote is formed, which is a diploid cell ready to develop into an organism.

• Cleavage occurs, where the zygote undergoes mitosis and splits into multiple cells.

• The mass of cells formed is called a morula, which later develops into a blastocyst with outer trophoblast cells and inner embryoblast cells.