Pregnancy Tracker - 5 weeks

So I'm going to do a weekly pregnancy tracker, where I can track what's going on with the baby and myself.  I did this with Carter and I LOVED it.  It really kept me in-tune with my body, the baby, and what to expect.  Speaking of what to expect, I have been informed that I need to go pick up a copy of "What to Expect When Mommy is Expecting."  It's on my list of items to take to Tahoe.

On to the Tracker:

Deep in the, uterus the embryo is growing at a furious pace. At this point, he's about the size of a sesame seed, and he looks more like a tiny tadpole than a human. He's now made up of three layers — the ectoderm, the mesoderm, and the endoderm — which will later form all of his organs and tissues.

The neural tube — from which your baby's brain, spinal cord, nerves, and backbone will sprout — is starting to develop in the top layer, called the ectoderm. This layer will also give rise to his skin, hair, nails, mammary and sweat glands, and tooth enamel.

His heart and circulatory system begin to form in the middle layer, or mesoderm. (This week, in fact, his tiny heart begins to divide into chambers and beat and pump blood.) The mesoderm will also form your baby's muscles, cartilage, bone, and subcutaneous (under skin) tissue.

The third layer, or endoderm, will house his lungs, intestines, and rudimentary urinary system, as well as his thyroid, liver, and pancreas. In the meantime, the primitive placenta and umbilical cord, which deliver nourishment and oxygen to your baby, are already on the job.

(courtesy of http://www.babycenter.com/)