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Today we are going to talk about human development.
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More specifically, we're going to be looking at the three main germ layers that all of the bodies, organs, and tissues are derived from.
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So as you can see here, in our diagram, we have a 16 -day -old embryo, which has differentiated into those three separate germ layers.
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Now, the top layer is referred to as the ectoderm.
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The middle layer is referred to as the mesoderm, and then the innermost layer of cells are called the endoderm.
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Now, each one of these germ layers is going to assist in developing the different organs and tissues of a fully developed fetus.
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So we're going to go through each one of these and talk a little bit about what it's going to result in in this development.
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So starting with the ectoderm, ecto means outside.
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So it is the referred to as the outer skin.
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So that is going to result in the epidermis or our skin, as well as hair, nails, so on and so forth.
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It also leads to the brain and the spinal cord development.
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More specifically associated with the brain is the neural tube.
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So if you take a look at the diagram to the right here, that shows it a little bit better.
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So the blue circle represents the neural tube, which more specifically is going to lead to the development of the brain.
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Okay, so next up we have the mesoderm, which as you can see, it develops into a lot.
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So starting with the noticord, which you can also see over in the right diagram here...