L2 Amino Acids & Proteins

Question 1

Proteins are made from;

Answer 1

long chains of AMINO ACIDS

Question 2

AMINO ACID:
what does it contain
when AA join what end do they always join on to
what isomer ONLY Is found in proteins

Answer 2

contains; carboxyl group (COOH), carbon containing group, & amino group (NH2)

N- terminus; start of PPC. AMINO TERMINUS
C- terminus, end of PPC, CARBOXYL TERMINUS

C FOR C

AA always joim to the CARBOXYL end
ONLY L-ISOMER FOUND IN PROTEINS NBNBNB

1 exception is GLYCINE - R group only contains 1 hydrogen

Question 3

when does a polypeptide form?

in what type of reaction does it form

Answer 3

when 2 or more AA join

form by CONDENSATION reactions (H20 is released )

Question 4

PROTEINS - 4 structural levels

Answer 4

primary; sequence of AA in a protein

secondary; HB form between AA & coils into alpha helix of beta pleated sheet - have REPEATING structures
.
tertiary- coils up even more (folded)
final structure of proteins formed by a single polypeptide bond,

quatenary; final part of 3D structure for proteins formed by many polypeptide chains

Question 5

each structure holds what bonds together

Answer 5

primary; polypeptide bonds
secondary; HB
tertiary and quaternary; HB, Ionic bonds, Disulfide bonds, hydrophobic and philic bonds.

Question 6

2 Types of proteins in TERTIARY structure

Answer 6

Globular & Fibrous

Globular; round, compact protein
coiled up - hydrophilic on outside, hydrophobics on inside
thus, - SOLUBL in liquids & easily transported
Function; DO something

Fibrous; long, thin , insoluble polypeptide chains
tightly packed into a rope like structure
found in SUPPORTIVE tissue
Function; STRUCTURAL role

Question 7

Primary structure depends on what?

Answer 7

PS - the SEQUENCE of AMINO ACIDS ina polypeptide chain

the AA that form are determined by the NUCLEOTIDES in the genes (base sequence of DNA )

Question 8

SUB-UNIT of a protein complex is a ?

Answer 8

POLYPEPTIDE CHAIN

Question 9

TERTIARY structure - TYPE OF COMPOSITION ?

Answer 9

final structure for AA - single PPB

HYDROPHOBIC effect - phobic inside, philic outside

Question 10

QUATERNARY -what forms due to several polypeptide chains ?

Answer 10

protein complex with each PPC called a SUBUNIT

Question 11

Protein folding is based on what ? (BONDS)

Answer 11

HB
Ionic
hydrophobic
Van der Vaals

Question 12

hydrophobic effect

Answer 12

(HYDRO) phobic inside. philic outside - makes it more SOLUBLE

Question 13

PROTEIN misfolding

Answer 13

BADDD

cause diseases - ALZHEIMERS