Cell Specializations

After fertilization, you have one cell and it starts dividing into identical cells. These cells don’t have specific functions. These are non specialized or STEM CELLS. They are found in fetuses and embryos

Morula is a well defined ball of cells.

A blastocyst has a big gap because you have two layers of cells (outside ring and ball in the middle)

The blastocyst becomes an embryo (outer ring becomes placenta, the inside becomes everything the fetus needs)

Properties of stem cell

Stem cells do not have specific functions

They have endless self renewal (can make copies of themselves forever)

Stem cells can turn into any kind of cell (called potency)

There are 220 different cells. The stem cell can turn into one of them.

Differentiation is the process of developing specialized structures and functions.

The DNA in every cell is the same

Every cell contains all of the genes for that organism. To differentiate, you activate or deactivate those genes that turn into that cell. In stem cells, all genes are active.

Totipotent - Can become literally anything

Pluripotent- Can become any fetal cell, but not a placental cell

Multipotent - can become any member of a family of cell (any hair cell, blood cell, bleh)

Having a big SA:Vol ratio means you diffuse better. Having a lot of side length means you have a big SA:Vol ratio, and diffuse worse. Cells increase surface area without increasing volume by becoming tall, becoming squished, and developing bristles.