Chapter 1: Macromolecules

Question 1

What are hydrogen bonds?

Answer 1

• Hydrogen bonds are not covalent
  (do not involve the sharing of electrons)
• Hydrogen bonds are attractive forces

Question 2

Is water polar?

Answer 2

Yes, water is a polar molecule.

Question 3

How many H bonds can each water molecule make?

Answer 3

4 H bonds.

Question 4

How are polymers formed?

Answer 4

They are formed by
- Dehydration/Condensation reactions.

Question 5

How are polymers broken down?

Answer 5

Hydrolysis

Question 6

How many bonds is carbon assumed to have?

Missing bonds are assumed to be what?

Answer 6

Carbon is always assumed to have 4 bonds,

if you see less than 4,

the missing bonds are assumed to be with Hydrogen.

Question 7

What is the functions of carbohydrates?

Answer 7

• Fuel for cells.
• Carbon source to build other molecules.

Question 8

What is the formula for a simple sugar (monosaccharides) ?

Answer 8

(CH2O)n

Question 9

What happens to sugars in aqueous solutions?

Answer 9

They form rings.

Question 10

What is the monomer of carbohydrates?

Answer 10

Monosaccharides.

Question 11

What is the polymer of carbohydrates?

Answer 11

Polysaccharides.

Question 12

How are monosaccharides joined?

Answer 12

Glycosidic linkage.

Question 13

What are the main functions of polysaccharides in plants?

Answer 13

• Energy storage: Starch
• Structural support: Cellulose

Question 14

Why can’t some animals digest cellulose?

Answer 14

They lack the enzyme that can break down beta glucose.

Question 15

What are the main functions of polysaccharides in animals?

Answer 15

• Energy storage: glycogen
• Structural support: Chitan (lobsters, etc)

Question 16

Why is glycogen so branched and what does it allow for?

Answer 16

Increased water solubility which allows for several sites to break down

thus more efficient storage and release of energy.

Question 17

Are lipids polymers?

Answer 17

No

Question 18

Are lipids soluble in water? Why or why not?

Answer 18

Lipids are insoluble in water as they are hydrophobic

Question 19

What is the structure of a fat?

Answer 19

Fats are constructed from glycerol (a 3-C alcohol)
& three fatty acids

Question 20

What type of bond links fat?

Answer 20

ester linkage (dehydration rxn)

Question 21

What are two other names for fats?

Answer 21

triglycerides or triacylglycerols

Question 22

What are the main functions of fats?

Answer 22

1. Storage of Energy: fats contain twice as much E per
   gram as polysaccharides.
2. Protects internal organs
3. Prevents heat loss: whales & seals have a
   layer of fat to keep them warm

Question 23

What are the two different types of fats?

Answer 23

Saturated and Unsaturated fats

Question 24

What are the main differences between saturated and unsaturated fats?

Answer 24

Saturated: - No carbon double bond
- solid at room temp
- from animal sources
Unsaturated: - contain at least one carbon double bond
- liquid at room temp
- from plants and fish

Question 25

What is the makeup of a phospholipid?

Answer 25

- A glycerol molecule – Two fatty acid molecules – A phosphate group (negatively charged) – Small hydrophilic group attached to the phosphate

Question 26

Which parts of a phospholipid are responsible for what?

Answer 26

fatty acid tails are hydrophobic (non-polar) phosphate group is hydrophilic (polar)

Question 27

What happens to phospholipids in water?

Answer 27

They form micelles (heads point out toward the water, tails in away from the water)

Question 28

What is the main purpose of phospholipids?

Answer 28

To make cell membranes from lipid bilayers

Question 29

What is the structure of a steroid?

Answer 29

4 fused carbon rings

Question 30

What is the most important steroid and what is its function?

Answer 30

Cholesterol: component of cell membranes and is also the starting compound for other steroids, such as estradiol, testosterone, progesterone and cortisol

Question 31

What are proteins?

Answer 31

The molecular tools of the cell

Question 32

What is the monomer of protein?

Answer 32

amino acids

Question 33

What is the polymer of protein?

Answer 33

polypeptides

Question 34

What causes amino acids to differ?

Answer 34

Whatever is bonded to the backbone (always N-C-C chain)

Question 35

Can a protein consist of multiple polypeptides?

Answer 35

yes

Question 36

What is the bond between amino acids called?

Answer 36

peptide bonds

Question 37

How many amino acids are polypeptides made of?

Answer 37

1000s

Question 38

What causes a polypeptide to become a protein?

Answer 38

They are folded into a certain shape to serve a specific function

Question 39

What is protein denaturation?

Answer 39

Proteins lose their 3D structure when heated or exposed to certain chemicals

Question 40

What is the purpose of nucleic acids?

Answer 40

Store & transmit heritable information (Blueprints)

Question 41

What are the two nucleic acids?

Answer 41

– Deoxyribonucleic acid (DNA) double-helix – Ribonucleic acid (RNA) single-helix

Question 42

What are genes?

Answer 42

A gene is the basic physical and functional unit of heredity. Genes, which are made up of DNA, act as instructions to make molecules called proteins.

Question 43

What are chromosomes?

Answer 43

strands of DNA containing 1000s of genes

Question 44

How does DNA synthesize?

Answer 44

Replication

Question 45

How does RNA synthesize?

Answer 45

DNA directs the synthesis of RNA through the process of transcription

Question 46

What are the 3 types of RNA?

Answer 46

1. Messenger RNA (mRNA) directs the synthesis of a protein through the process of translation 2. Transfer RNA (tRNA) acts as a “delivery vehicle” during the process of protein synthesis 3. Ribosomal RNA (rRNA) makes up the structure of the ribosome

Question 47

What is the monomer of nucleic acids?

Answer 47

nucleotides

Question 48

What is the polymer of nucleic acids?

Answer 48

polynucleotides

Question 49

What are nucleotides comprised of?

Answer 49

1. A N-containing base (called nitrogenous base) – There are 2 types of N-bases: purines and pyrimidines – the sequence of bases for each gene is unique 2. Pentose sugar 3. Phosphate: attached to carbon 5 of sugar

Question 50

What are the two pentose sugars?

Answer 50

Deoxyribose (DNA) missing one O Ribose (RNA)

Question 51

What nitrogen bases are pyrimidines?

Answer 51

- DNA: cytosine (C) and thymine (T) - RNA: cytosine (C) and uracil (U) - (C,U,T the Py)

Question 52

What nitrogen bases are purines?

Answer 52

- DNA & RNA: adenine (A) and guanine (G)

Question 53

How are nucleic acids formed?

Answer 53

Connect pentose sugar of one nucleotide to the phosphate of another nucleotide (forms the sugar phosphate backbone)

Question 54

What is the link between nucleotides called?

Answer 54

phosphodiester linkage

Question 55

Where are the nitrogen bases located in DNA?

Answer 55

in the double-helix

Question 56

How are the two strands of the double helix held together?

Answer 56

H-bonds

Question 57

What is the complementarity of DNA?

Answer 57

A-T G-C

Question 58

How many H-bonds between A-T?

Answer 58

2

Question 59

How many H-bonds between G-C?

Answer 59

3

Question 60

In what manner are DNA strands joined?

Answer 60

anti-parallel

Question 61

What does the sequence of bases determine?

Answer 61

What the gene will produce (like a code)

Question 62

What allows RNA to have many functions?

Answer 62

It can bind to other regions and complement itself to form different shapes which allows for it to have many functions

Question 63

What is metabolism?

Answer 63

The combination of anabolic and catabolic reactions

Question 64

What is catabolism?

Answer 64

The breakdown of bigger molecules into smaller ones which is an exergonic rxn (releases energy)

Question 65

What is anabolism?

Answer 65

The process of building bigger molecules from smaller ones which is an endergonic rxn (takes in energy)