Unit 2: Proteins

Question 1

Proteins are one of the most ___, ___ in living systems

Answer 1

abundant, organic molecules

Question 2

Proteins are the main molecules that carry out

Answer 2

the functions of the cell.

Question 3

The major reason that proteins are so varied in their function is due to

Answer 3

their ability to bind other molecules.

Question 4

Ligand

Answer 4

A molecule that a protein binds

Question 5

Protein Structure

Answer 5

Amino acid polymers arranged in a linear sequence, with each protein having a unique function and structure.

Question 6

Binding Site

Answer 6

The place on a protein where binding occurs; determined by the protein’s shape.

Question 7

Protein provides (8)

Answer 7

Proteins may be; structural, contractile,
protect, defend,
transport, store,
communicate, regulate,
toxins, enzymes.

Question 8

Various proteins can bind other proteins, such as (6)

Answer 8

DNA, RNA, lipids, carbohydrates, ions, or small molecules.

Question 9

Proteins are synthesized by _______, which attach ______ together to form a _____, which folds into its three-dimensional shape.

Answer 9

ribosomes, amino acid polymers, polypeptide

Question 10

Protein Folding is critical for__ and is aided by __

Answer 10

Structure & function; chaperonins

Question 11

Chaperonins

Answer 11

Assist in protein folding, prevent aggregation, and disassociate post-folding.

Question 12

Denaturation is an alteration in protein___ and is caused by changes in___(3).

Answer 12

shape (not sequence). temp, pH, or chemicals.

Question 13

Reversible Denaturation

Answer 13

Proteins can refold and regain function after denaturation.

Question 14

Irreversible Denaturation

Answer 14

Permanent loss of protein function due to denaturation.

Question 15

The shape of a protein is crucial for its ___ and is determined by its ___(4) levels of structure.

Answer 15

function. primary, secondary, tertiary, and quaternary.

Question 16

Enzyme

Answer 16

A protein that acts as a biological catalyst, facilitating specific chemical reactions.

Question 17

Active Site

Answer 17

The specific region on an enzyme where the substrate binds and the chemical reaction occurs.

Question 18

Primary Structure

Answer 18

The unique sequence of amino acids in a protein’s polypeptide chain.

Question 19

The gene encoding the protein ultimately determines

Answer 19

the unique sequence for every protein.

Question 20

Secondary Structure

Answer 20

The local folding patterns of the polypeptide chain, often forming α-helices or β-pleated sheets.

Question 21

Tertiary Structure is a __ structure of a protein, influenced by interactions __.

Answer 21

three-dimensional; among R groups

Question 22

When a protein loses its three-dimensional shape, it

Answer 22

may no longer be functional.

Question 23

Quaternary Structure

Answer 23

The structure that results from the interaction of multiple protein subunits.

Question 24

Hydrogen bonds are __ bonds formed between __, crucial for maintaining protein __ structures.

Answer 24

Weak chemical, hydrogen atoms and other atoms, secondary and tertiary

Question 25

Disulfide bond is a __ bonds formed between two__ & two__, contributing to protein__.

Answer 25

Covalent, cysteine amino acids, sulfhydryl groups, folding and stability

Question 26

Insulin is a __ protein that forms a __ structure through __ (2) bonds, crucial for regulating blood sugar levels.

Answer 26

globular, quaternary, hydrogen and disulfide

Question 27

Amino acids are protein __

Answer 27

monomers

Question 28

What is the fundamental structure of an amino acid?

Answer 28

It includes a central carbon atom bonded to an amino group, a carboxyl group, a hydrogen atom, and an R group.

Question 29

What is an R group in an amino acid?

Answer 29

Atom or group of atoms bonded to the central carbon atom, determining the amino acid’s chemical nature.

Question 30

The R group determines whether an amino acid is __(4)?

Answer 30

It determines whether the amino acid is acidic, basic, polar, or nonpolar.

Question 31

The sequence and the number of amino acids ultimately determine the protein’s

Answer 31

shape, size, and function.

Question 32

A peptide bond is a__ bond formed between__ through a dehydration reaction, involving the combination of one amino acid’s__ group with another amino acid’s__ group, releasing a water molecule.

Answer 32

Covalent, amino acids, carboxyl, amino

Question 33

Polypeptide

Answer 33

A polymer of amino acids.

Question 34

How are amino acids linked in a polypeptide?

Answer 34

By peptide bonds.

Question 35

What terminal is the free amino group located on a polypeptide chain?

Answer 35

At the N terminal end.

Question 36

What terminal is the free carboxyl group located in on a polypeptide chain?

Answer 36

At the C terminal end.

Question 37

Protein is made up of a __ that have combined together, often with__ prosthetic groups, possessing a distinct shape and unique function.

Answer 37

Polypeptide(s), non-peptide,

Question 38

Essential amino acids are__ that the human body cannot __ and must be obtained from the__ to build proteins.

Answer 38

amino acids; produce; diet

Question 39

The “alpha carbon” is found where?

Answer 39

it is the carbon adjacent to the hydroxyl on a carbonyl

Question 40

Ribosomes are composed of what types of molecules?

Answer 40

proteins and RNA

Question 41

An alpha helix is an example of a ____ structure, and is held together by ___.

Answer 41

secondary, hydrogen bond

Question 42

What are some causes of disease

Answer 42

Infection, genetic (mutations, inherit genes) and environmental factors (diet, exposure to chemicals)