Z3295026

From Embryology
Revision as of 14:54, 13 August 2009 by Z3295026 (talk | contribs)

Lecture Questions- Student: z3295026


Lab 1 Questions:

1. What is the protein that the sperm binds to on the surface? Zona pellucida protein ZP3 acts as receptor for sperm


2. Name the three stage of follicle development in the ovaries?

1. Primordal follicle

2. Secondary follicle- (Pre-antral follicle)

3. Graffian follicle- (Antral follicle):is the mature follicle


Lab 2 Questions:


1. What factor do the synctiotrophoblast cells secrete to support the ongoing pregnancy?

Syncitiotrophoblasts - form a multinucleated cytoplasmic mass by cytotrophoblast cell fusion and both invade the decidua and secrete hCG which act on ovaries to stop menstration , cell inovaries secretes hormones to to stop the cycle from continuiing (corpus lutuem)


2. What does the corpus luteum secrete to prevent continuation of the menstrual cycle?

The corpus luteum produces progesterone. Progesterone makes the lining of the uterus thick for implantation and is necessary to sustain a healthy pregnancy. The corpus luteum produces progesterone until the placenta begins to take over progesterone production around ten weeks gestation.


3. What are the 2 main tissues to be derived from the germ cell layer continuous with the lining of the amniotic sac?

formed by two germ cell layers including :

1.Epiblast= ecoderm which forms= nervous system ( edge of ecoderm= epidermis)

2.Mesoderm ( spread entire cavity)= extra-embryonic mesoderm (connective tissue in orgin)

3.Endoderm'


Lab 3 Questions:

What period of human development (in weeks) do the 23 Carnegie stages cover? 8(weeks) and 4(days) to full development


What part of the somite will contribute to the vertebral column? Only the ventromedial portion known as the sclerotome contributes the axial vertebral column


At what Carnegie stage does the human neural tube normally completely close? Stage 13 (4 weeks) the neural tube is normally completely closed