November 19 - Happy Birthday George Emil Palade

Posted on November 19, 2018

Today's famous birthday (born on this date in 1912) has been called "the most influential cell biologist ever" - and I've never even heard of him!

Romanian scientist George Emil Palade won a Nobel prize in Physiology and Medicine (along with two others). The achievement that earned him this prize is strides taken with electron microscopes, discovering ribosomes, and procedures used to study different parts of the cell and to discover how they function.

Okay, so what's an electron microscope? What different parts are in a cell? What are ribosomes?

An ordinary microscope lights up a specimen (with, you know, light) and uses lenses to greatly enlarge the specimen. You can magnify things 4 to 2,000 times with this sort of microscope.

An electron microscope uses a beam of electrons instead of light, to "light up" the specimen, and uses electron lens systems to magnify up to about 10,000,000 times!

With so much magnification power, we can see the super teeny tiny parts that make up our really tiny cells. These parts are called organelles (just like the parts of the body are called organs).

Notice that, in these two comparisons (above and below), the electron
microscope has way better resolution even when it is at the same
magnification as the light microscope!

Some examples of cell organelles include:

The nucleus - This is sort of like the cell's brain. It stores and maintains DNA and makes copies of bits of the genetic code as commands or instructions that other organelles then carry out.

Vacuoles - These are storage compartments that usually hold water or enzymes in a watery solution. Sometimes vacuoles hold solids.

Endoplasmic Reticulum - This organelle moves molecules to and from the nucleus.

Mitochondria - These produce energy by burning sugars.

Ribosomes - These organelles build proteins.

Golgi Apparatus - This organelle changes newly-made proteins and fats, getting them ready to be stored or to be sent out to other cells.

Cell Membrane - This is like a thin "skin" that protects the cell and keeps some sorts of molecules out while allowing other sorts in.

Cytoplasm - This substance fills in the spaces between organelles and helps hold them in place.

Did you notice that ribosomes build proteins? That's a super-power you really want your cells to have! Proteins are really large molecules made of long chains of amino acids. They are the building blocks of everything from muscles to hair to skin to cell membranes. Proteins also are crucial for lots of bodily processes like digesting food.

And ribosomes are the construction crew that put together these long chains of amino acids, following instructions from the nucleus.

Here is an animation that helps us understand how ribosomes work. This is another short video on ribosomes and protein creation - this one for younger viewers.