Section 2: Proteins

Question 1

What are atoms composed of?

Answer 1

Protons, neutrons, and electrons

Question 2

What determines the element of an atom?

Answer 2

The number of protons

Question 3

What charge do protons have?

Answer 3

Positive charge

Question 4

What charge do electrons have?

Answer 4

Negative charge

Question 5

What is the charge of neutrons?

Answer 5

No charge

Question 6

What are molecules formed from?

Answer 6

Atoms

Question 7

Define ionic bonds.

Answer 7

Chemical bonds formed when one atom transfers electrons to another, creating oppositely charged ions

Question 8

What happens during the formation of an ionic bond between sodium and fluorine?

Answer 8

Sodium transfers an electron to fluorine

Question 9

What are covalent bonds?

Answer 9

Chemical bonds where outer electrons are shared between atoms

Question 10

What is a single covalent bond?

Answer 10

When a pair (2) of electrons are shared

Question 11

What is a double covalent bond?

Answer 11

When two pairs (4) of electrons are shared

Question 12

How many covalent bonds can carbon form?

Answer 12

4

Question 13

How many covalent bonds can hydrogen form?

Answer 13

1

Question 14

How many covalent bonds can oxygen form?

Answer 14

2

Question 15

How many covalent bonds can nitrogen form?

Answer 15

3

Question 16

What is a nonpolar covalent bond?

Answer 16

A covalent bond where electrons are shared evenly

Question 17

What is a polar covalent bond?

Answer 17

A covalent bond where electrons are unequally shared

Question 18

What does electronegativity determine?

Answer 18

Electron sharing behavior

Question 19

Which elements are highly electronegative?

Answer 19

Oxygen, Nitrogen, and Chlorine

Question 20

What do the symbols ẟ+ and ẟ- represent?

Answer 20

Slightly positive and slightly negative charges

Question 21

What are hydrogen bonds?

Answer 21

Weak electrostatic bonds between ẟ+ and ẟ- areas

Question 22

What types of molecules are hydrophilic?

Answer 22

Molecules attracted to water and can dissolve in water

Question 23

What types of molecules are hydrophobic?

Answer 23

Molecules repelled by water

Question 24

What is an amphiphilic molecule?

Answer 24

A molecule with both hydrophilic and hydrophobic parts

Question 25

What are cell membranes primarily composed of?

Answer 25

Phospholipids

Question 26

What are large biological molecules made of?

Answer 26

Polymers made from repeated subunits called monomers

Question 27

What are the monomers and examples of polymers for carbohydrates?

Answer 27

Monomers: sugars; Polymers: glycogen

Question 28

What are the monomers and examples of polymers for lipids and fats?

Answer 28

Monomers: fatty acids; Polymers: phospholipids

Question 29

What are the monomers and examples of polymers for proteins?

Answer 29

Monomers: amino acids; Polymers: enzymes (e.g. salivary amylase)

Question 30

What are the monomers and examples of polymers for nucleic acids?

Answer 30

Monomers: nucleotides; Polymers: DNA, RNA

Question 31

What are the three parts of an amino acid?

Answer 31

Amino group, central carbon (alpha), carboxyl group

Question 32

How can R groups of amino acids be classified?

Answer 32

As nonpolar, polar, positively charged, or negatively charged

Question 33

What process combines two amino acids into a peptide molecule?

Answer 33

Dehydration synthesis

Question 34

What type of bond joins two amino acids in a peptide molecule?

Answer 34

Peptide bond

Question 35

What are the four levels of protein structure?

Answer 35

Primary, secondary, tertiary, and quaternary

Question 36

What characterizes primary protein structure?

Answer 36

The sequence of amino acids joined by peptide bonds

Question 37

What characterizes secondary protein structure?

Answer 37

Interactions between amino acids generate alpha-helix or beta-pleated sheet structures

Question 38

What characterizes tertiary protein structure?

Answer 38

Large bends and folds influenced by R group interactions

Question 39

What characterizes quaternary protein structure?

Answer 39

Two or more folded proteins combine to form a final 3D structure

Question 40

What effect does denaturing have on proteins?

Answer 40

It alters the 3D structure and can affect function

Question 41

What role do enzymes play in living organisms?

Answer 41

They catalyze chemical reactions

Question 42

What is an active site of an enzyme?

Answer 42

The location that binds the substrate

Question 43

What does Vmax represent in enzyme kinetics?

Answer 43

The maximal rate of reaction reached when the curve plateaus

Question 44

What does Vmax/2 represent in enzyme kinetics?

Answer 44

50% of the maximal rate of reaction