biology i proteins regents biology 2006-2007 proteins: multipurpose molecules
TRANSCRIPT
Biology I
Proteins
Regents Biology 2006-2007
Proteins:
Multipurpose molecules
Biology I collagen (skin)
Proteins
insulin
Examples muscle skin, hair, fingernails, claws
collagen, keratin
pepsin digestive enzyme
in stomach
insulin hormone that controls blood
sugar levels
pepsin
Biology I
Proteins Function:
many, many functions hormones
signals from one body system to anotherinsulin
movementmuscle
immune systemprotect against germs
enzymeshelp chemical reactions
Biology I
Proteins
Building block =
aminoacid
aminoacid–
aminoacid–
aminoacid–
aminoacid–
—N—H
H
H|
—C—|
C—OH
||O
variable group
amino acids
20 different amino acidsThere’s
20 of us…like 20 different
letters in analphabet!
Can make lots of different
words
Biology I
Amino acid chains Proteins
amino acids chained into a polymer
Each amino acid is different some “like” water & dissolve in it
some “fear” water & separate from it
amino acid amino acid amino acid amino acid amino acid
Biology I
Water-fearing amino acids Hydrophobic
“water fearing” amino acids try to get away from water in cell
the protein folds
Biology I
Water-loving amino acids Hydrophillic
“water loving” amino acids try to stay in water in cell
the protein folds
Biology I pepsin
For proteins: SHAPE matters!
collagen
Proteins fold & twist into 3-D shape that’s what happens in the cell!
Different shapes = different jobs
hemoglobingrowth
hormone
Biology I
It’s 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)
folded
unfolded“denatured”
In Biologyit’s the SHAPEthat matters!
Biology I
Let’s EAT some
Proteins!
Biology I
Activities demo raw egg vs. cooked egg
drop raw egg into boiling water, like egg drop soup
compare raw egg to hard-boiled egg
demo cheese-making with heated milk & vinegar
make yogurt