Development (Ch 42b) Flashcards
What are the characteristics of protostomes?
- Spiral cell cleavage
- Blastopore = mouth first
- determinate cell fate
- schizocoelous
What are the characteristics of deuterostomes?
- radial cell cleavage
- Blastopore = anus first
- indeterminate cell fate
- enterocoelous
All mammal fetuses begin the same, with an ancestral structure called the _______ _______
Bipotential Gonads.
In males, the testes factor inhibits the _____ ______ and turns on ______ via ______ ______.
Mullerian ducts; testosterone; leydig cells
In females, there are no testes factor to inhibit _____ ______
Mullerian ducts.
In females, what happens to Mullerian ducts?
They become oviducts.
What is the function of the yolk sac?
It attaches the outside developing embryo and is connected to the umbilical cord.
What is the function of the chorion and amnion?
The chorion and the amnion together forms the amniotic sac.
What is the amniotic sac?
A bag of fluid inside a woman’s womb (uterus) where the unborn baby develops and grows.
What is the allantois and its function?
A sac-like structure that forms part of a developing amniote’s conceptus. It helps the embryo exchange gases and handle liquid waste.
What are the three phyla under protostomes?
Mollusca, Annelida and Arthropoda
Which phylas are under deuterostomes?
Chordata, Echinodermata, Hemichordata.
What are the three tissue types that form during gastrulation?
Ectoderm, Mesoderm, and Endoderm.
What is the difference between a true coelom and a pseudocoelom?
A coelom is a body cavity completely within the mesoderm. A pseudocoelom is a cavity between the mesoderm and the endoderm.
What are the functions of a coelom?
A hollow, fluid-filled cavity found in many living things, where it acts as a protective cushion for their internal organs.