Embryology: 3 DONE

Question 1

What is gametogenesis?

Two types of gametogenesis?

What is oogenesis?
What is spermatogenesis?

We had a question about haploid

Answer 1

Gametogenesis– the process in which cells undergo meiosis to form gametes

Oogenesis– All potential eggs are there when a female is born. They start to undergo first meiotic division to replicate DNA, but stop before its finished

• After onset of puberty, 1 oocyte matures e28 days and completes the first meiotic division
• After ovulation, second meiotic division begins – completes only if fertilized

Spermatogenesis– 2 haploid
secondary spermatocytes are formed

• Each contains 22 autosomes and 1
  sex chromosome
• Secondary spermatocytes divide
  results in 4 sperm

Question 2

Describe fertilization

we also had a question about fertalization

Answer 2

Sperm and ovum meet in ampulla
(outer third) of the uterine tube

Chemical reaction prevents more than one sperm from entering the ovum – called the zona reaction

Restores the diploid number to form zygote

This process restores the diploid number of chromosomes, combining the genetic material from both parents and initiating the development of an embryo.

Question 3

Discuss susceptibility of a developing embryo in the first 8 weeks to environmental and chemical exposures

Period of?

Infections?
Environmental exposures?
Chemical exposures?

Know what teratogens are!!!

Answer 3

Period of highest risk

Teratogens such as:

Infection: Rubella, toxoplasma, TORCH

Environmental exposures: heat and toxins

Chemical exposures: Alcohol and medications