Structure And Function 3

Question 1

Proteins

Answer 1

Over 50% of the dry mass of most cells
Instrumenta, in almost everything an organism does

Question 2

Protein functions

Answer 2

Structural support
Storage
Transportation
Cellular communication
Movement
Defense against foreign substances
Catalyst

Question 3

Most important function of a protein

Answer 3

Catalysts in cells
Regulating Metabolism by selectively accelerating certain chemical reactions without being consumed

Question 4

Shape of proteins

Answer 4

Each one has complex three-dimensional shape
U branched polymers constructed from the same 20 amino acids
One or more polypeptid3s folded or coiled into a specific conformation

Question 5

Polypeptides

Answer 5

Polymersof amino acids

Question 6

Amino acids have (structure)

Answer 6

Both carboxyl and amino groups
An asymmetric carbon atom (alpha carbon) at the center
And four components attached to the carbon:
- a hydrogen atom
- a carbon group
- an amino group
- avaliable Rgroup (side chain)

Question 7

A r group may be

Answer 7

As simpleasa hydrogen atom
Or a carbon skeleton with various functions algroups attached

Question 8

The physical and chemical properties of the r group determine

Answer 8

The unique characteristics of a particular amino acid

Question 9

If a nonpolar R group presents, the amino acid is

Answer 9

Hydrophobic

Question 10

If a polar r group presents, the amino acid is

Answer 10

Hydrophilic

Question 11

There is also a group of amino acid that has functional groups that are charged at

Answer 11

Cellular pH
Ionized

Question 12

A basic or acidic amino acid is based on

Answer 12

The R group
All amino acids have carboxyl and amino groups. The pH is looking just at the r group

Question 13

Dehydration reaction

Answer 13

Amino acids are joined together
OH and H are removed from the end of two groups, forming h20 and a peptide bond between the new ends - which are a c-terminus (carboxyl group) and n-terminus (amino group)
A hydroxyl group is removed from the carboxyl end of one amino acid and a hydrogen atom from the amino groups of another

Question 14

Protein primary structure

Answer 14

Unique sequence of amino acids

Question 15

Protein secondary structure

Answer 15

Coils and folds in the polypeptide chain
Hydrogen bonds between the repeating coils and folds

Question 16

Protein tertiary structure

Answer 16

Determined by interactions among various side chains (r-groups)
Hydrogen bonds between polar and/or charged areas
Ionic bonds between charged r-groups
Hydrophobic interactions and van Der waals interactions among hydrophobic r groups

Question 17

Quarternary protein structure

Answer 17

Results when aprotein consists of multiple polypeptide chains

Question 18

Transthyretin

Answer 18

Globular protein founding the blood that transports vitamin A and a particular thyroid hormone throughout the body
Each of the identical four polypeptidechains that (together) make up transthyretin is composed of 127 amino acids

Question 19

Transthyretin secondary structure

Answer 19

Helix and pleated sheet

Question 20

Pleated sheet secondary structure

Answer 20

Two or more regions of the polypeptide lying side by side are connected by hydrogen bonds between parts of the two parallel polypeptide backbones
Found in many globular proteins
Dominate fibrous proteins

Question 21

Helix secondary structure

Answer 21

Delicate coil held together by hydrogen bonding between every fourth amino acid

Question 22

Disulfide bridges

Answer 22

Strong covalent bonds between sulfhydryl groups of two cysteine monomers

Question 23

Globular transthyretin protein is made up of how many polypetides

Answer 23

4

Question 24

Collagen is a fibrous protein made up of -#- polypeptides that are –structure–

Answer 24

3
Superceded j to a larger triple helix

Question 25

Hemoglobin (— protein) quaternary structure

Answer 25

Globular protein
Consists of four polypeptid3 subunits - two alpha two beta chains
Both types of subunits consist of primarily alpha-helical secondary structures,