Lecture 4 - Egg differentiation &
- The egg undergoes growth and differentiation prior to being arrested in
- Corona radiata is part of the cumulus oophorus, it is the inner most layer and
the layer closest to the zona pellucida.
- The cumulus oophorus and corona radiata are made of cells. The zona
pellucida is a protein shell.
- Zona pellucida surrounds the oocyte and polar bodies.
- Reptiles, amphibians, and birds all have large yolk sacs in their eggs because
they lay eggs rather than carry.
- The yolk sacs in mammalian eggs are much smaller because the embryo is
attached to the mother and is able to get nutrient that way.
- Receptor mediated endocytosis allows for the yolk to enter the egg.
- No. of polar bodies found with the secondary oocyte depends on if the first polar
body divides again or not.
- Slide 15- two pro-nuclei is present showing that fertilization has occurred.
- Polar bodies either get absorbed into the egg or degraded.
- The longer a primary oocy