Exam 3 Flashcards
(151 cards)
What is morphogenesis?
The combination of gastrulation and organogenesis that results in an organism’s shape and body orientation.
What is the cortical granule
Structure in the egg that releases enzymes during fertilization that harden the zona pellucida and digest binding proteins on sperm to prevent polyspermy.
What is the zona pellucida/jelly coat?
structure in the egg that contains glycoproteins that protect the inner contents of the ovum until the acrosome reaction of fertilization and helps prevent polyspermy.
What is the vitelline layer?
Protects and gives shape to the egg yolk, protecting it from the egg white.
What is the acrosome?
Organelle in the sperm head that contains enzymes that will degrade the zona pellucida, allowing the sperm to reach the egg plasma membrane.
What is the fertilization envelope?
A layer that prevents additional sperm from reaching the egg; the egg’s “slow block”
What is special about the cleavage stage?
Cell division in the zygote does not equal an increase in size.
What are blastomeres?
Smaller cells within the zygote
When does a zygote become a blastula?
After over 100 blastomeres have been produced.
What is considered to be the first embryonic tissue?
the blastoderm
What is the fluid or yolk filled cavity that the blastoderm surrounds?
the blastocoel
What is the mammalian blastula called?
The blastocysts
What is the trophoblast?
The outer cell mass of a blastocyst
What will the inner cell mass become?
the embryo
What will the trophoblast become?
the embryonic placenta
Where do the morula and blastocyst stages take place?
The uterus. After that, all other processes happen in the uterine tube.
What are intrinsic factors?
Information inherited from the mother cells free-floating cytoplasmic molecules
What are extrinsic factors?
Information received from the cells surrounding environment
Define lateral, medial, dorsal, ventral, anterior, and posterior
left-right-back-front-head-feet
What are cytoplasmic determinants?
mRNA proteins found in the egg prior to fertilization
What is yolk polarity?
The area with the least amount of yolk will become the anterior of the embryo
What is induction in mammal embryo development?
cell-cell communication
What is the process of cleavage?
Rapid, multiple rounds of mitotic cell division where the overall size of the embryo does not increase.
What is the blastula?
The developing embryo following cleavage