The Embryo takes shape

In this post, I'll answer some questions about the following video, that will then help me to understand better the stem cell's debate.

The Embryo Takes Shape

• What directs the sequence of events that turn a blob of cells into an embryo with specialized tissues and organs?

The events that turn a blob of cells into a "specialized" embryo is called gastrulation, and is caused mainly by the action of DNA and genes

• The narrator says that “cells talk to each other.” What does that mean?

This means that cells can "communicate" with each other, through chemical messages. Chemicals in one cell can trigger a reaction in the cell next door that can spread into the cell nucleus, and turn genes on or off.

• How do cells in different parts of the embryo become different kinds of cells and organs?

In each type of cell, a different group of genes are turned on, and it makes the cell to construct a particular protein.

• What kinds of proteins are found in different cells and organs?

Collagen: skin, tendons and bones.

Keratin: hair.

Crystalin: makes the lens of the eyes clear.

Actin & Myosin: move muscles fibers.

Hemoglobin: carries oxygen from the lungs to the rest of the body through the blood to the rest of the body.

• What tells the cells which kinds of proteins to make?

Location seems to be the answer, as apparently cells "know where they are" and where they have to intervene. Chemical messages through cells are extremely useful for this part.

• What is the relationship between DNA, genes, and the proteins that are produced in cells?

The cell "machinery", after a short process, can read the DNA and turn on the correct gene, so that in the end they can finally build up a protein.