Z3217015

Apparently it did not save when I answered the questions in the class, so here I go again.

1) What is the protein that sperm binds to on the surface of the egg? Zona Pellucida protein ZP3

2) Name the 3 stages of follicle development in the ovary? 1-Primordial follicle 2-Preantral follicle 3-Antral follicle

--Mitchell Mathieson 13:10, 6 August 2009 (EST)

1. What factor do the synctiotrophoblast cells secrete to support the ongoing pregnancy? hCG - Human Chorionic Gonadotropin

2. What does the corpus luteum secrete to prevent continuation of the menstrual cycle? hCG - Human Chorionic Gonadotropin, which acts on the ovary, altering the secretion of oestrogen, and progesterone, altering menstrual cycle

3. What are the 2 main tissues to be derived from the germ cell layer continuous with the lining of the amniotic sac? Ectoderm, which forms nervous system tissue, and epidermis epithelia tissue types

--Mitchell Mathieson 13:14, 13 August 2009 (EST)

1. What period of human development (in weeks) do the 23 Carnegie stages cover? 8 weeks 2. What part of the somite will contribute to the vertebral column? Sclerotome 3. At what Carnegie stage does the human neural tube normally completely close? Carnegie stage 13

--Mitchell Mathieson 13:08, 20 August 2009 (EST)