Monday, January 26, 2009

My Little Seseame Seed Tadpole

So I decided not to write this weekend- nothing much to say for the most part. Still having cramps and getting worried. Still excited. Still can't wait to see the little one on the sonogram. So yeah nothing new.

But today is the start of week 5 and here is what they say about that stage...



Deep in your uterus your 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.

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