ZOOMING DOWN THE TREE
OF LIFE TO LIFE'S BUILDING BLOCKSAll key components of every living cell are made of macromolecules. These are very large molecules that determine the structural and functional properties of living cells. There are four different kinds of macromolecules -- carbohydrates, nucleic acids, proteins and lipids. They are called "macro" molecules for their very large size relative to other organic molecules. Explore the macromolecules in the Tree of Life by clicking on the squares with pictures, noticing the basic features of the macromolecules you find. Most macromolecules are polymers -long chains of similar subunits called monomers. What monomers can you find for the different kinds of macromolecules? |
|||
| CARBOHYDRATES |
|
|
From leaf to starch |
| PROTEINS |
From a monkey to the protein hemoglobin |
From the coccoon of a silk worm to the
protein fibroin |
From human hair to the protein keratin
From a bee to the protein mellitin |
| NUCLEIC ACIDS | |
||
| LIPIDS |
From an iguana to phospholipids
|
||
Compare the similarities and differences
between the chemistry of the biomolecules.
You
have found carbohydrates in maple syrup, in the tree trunk, and
in green leaves. What do they all have in common? What makes them
similar and what makes them different from the other groups of
macromolecules in a living cell?
How are lipids different
from the other three kinds of macromolecules?
In
how many places in a cell are those molecules distributed? Take
a look at the cell picture. and answer the following questions:
If you needed to collect the nucleic acids of DNA from a cell, where would you go?
_____________________________________________
Where is the most starch found in the plant cell?_________________________________________________________________________
Where do lipids appear primarily in a cell ? What do those places have in common?___________________________________________________________________________
Because they are the machines of the cell, proteins are found almost everywhere in the cell. Where are they probably NOT found?
______________________________________________________________________________