1. DNA

2. Multipurpose molecules
Proteins:
Multipurpose molecules

3. Proteins Examples insulin hemoglobin collagen (skin) muscle
fingernails, claws
skin
hair
enzymes
example: pepsin
hormones
example: insulin
hemoglobin
collagen (skin)

4. Proteins Function: many, many functions hormones movement
insulin
movement
muscle
immune system
protect against germs
enzymes
help chemical reactions

5. Proteins —N— H | —C— C—OH || O Building block = amino acids –
20 different amino acids
—N— H |
—C—
C—OH || O
variable group

6. Amino acid chains Proteins Each amino acid is different
amino acids chained into a polymer
amino acid
Each amino acid is different
some “like” water & dissolve in it
some “fear” water & separate from it

7. Water-fearing amino acids
Hydrophobic
“water fearing” amino acids
try to get away from water in cell
the protein folds

8. Water-loving amino acids
Hydrophillic
“water loving” amino acids
try to stay in water in cell
the protein folds

9. 3-D protein structure Proteins fold & twist into 3-D shape
that’s what happens in the cell!
It’s a helix or B sheet within a single region. Can have both in one protein but a specific region is one or another
growth hormone
hemoglobin
pepsin
collagen

10. Its shape that matters! Proteins do their jobs, because of their shape
Unfolding a protein destroys its shape
wrong shape = can’t do its job
unfolding proteins = “denature”
temperature
pH (acidity)
unfolded “denatured”
folded

11. Let’s eat some Proteins!