2.2 Linkages in Biological Molecules

Question 1

what are the monosaccharides of carbohydrates?

Answer 1

glucose, fructose, galactose

Question 2

what are four different types of lipids?

Answer 2

fats, phospholipids, steroids, waxes

Question 3

what makes lipids unique compared to other macromolecules?

Answer 3

there subunits do not repeat

Question 4

what is the subunit of proteins?

Answer 4

Proteins are amino acids

Question 5

What are the polypeptides? What do they undergo before turning into a protein?

Answer 5

polypeptides are long chains of amino acids undergo specific folding before it becomes a functional protein

Question 6

what are the three parts of nucleic acids?

Answer 6

nitrogen base, 5-carbon sugar such as a ribose or deoxyribose, PO4 group

Question 7

what macromolecules are hydroxyl groups found? (4)

Answer 7

carbs, fats (glycerol), proteins, nucleic acids

Question 8

where are carbonyl groups found?

Answer 8

in carbohydrates in linear form such as aldehydes and ketones

Question 9

where are amino groups found?

Answer 9

in proteins

Question 10

where are phosphate groups found?

Answer 10

in phospholipids, DNA, RNA, ATP

Question 11

where are thiol or sulfhydryl groups found?

Answer 11

amino acids, or proteins

Question 12

how is a glycosidic bond formed?

Answer 12

a bond formed between the hydroxyl groups on two adjacent sugars

Question 13

how is an ester linkage formed?

Answer 13

a bond formed between the hydroxyl of glycerol and a carboxyl group of the fatty acid to form triglyceride

Question 14

how is an amide linkage formed? what is this also called?

Answer 14

a bond formed between the carboxyl on an amino acid and an amine on an adjacent amino acid also called a peptide bond

Question 15

how is a phosphodiester bond formed?

Answer 15

forms between the hydroxyl on one nucleotide and the phosphate on an adjacent nucleotide

Question 16

why are carbohydrates important (3)? b,c,e

Answer 16

-building material

-cell surface markers

-important energy source for organisms

Question 17

what is the ratio of carbohydrates? what is the chemical formula of carbohydrates? what are the different types of carbohydrates? what is the suffix of carbohydrates?

Answer 17

-1:2:1 ratio CHO

-chemical formula is CnH2nOn

-monosaccharides, oligosaccharides, polysaccharides

-suffix “os” glucose, sucrose

Question 18

what are monosaccharides and what are they important for? what form are these molecules most often found as?

Answer 18

-simple sugar molecules important for energy transfer in the blood

-they are most often found as pentose or hexose rings

Question 19

what are important examples of polysaccharides 5?

Answer 19

glucose, fructose, galactose, ribose, deoxyribose sugars

Question 20

what is glucose in terms of it’s chain? what is it found in?

Answer 20

-a six-carbon chain with an aldehyde in linear form

-found in plants and animals

Question 21

what is fructose in terms of it’s chains?

Answer 21

-a six-carbon chain with ketone in linear form

Question 22

what is galactose in terms of it’s chain?

Answer 22

-a six-carbon chain with an aldehyde in linear form but a different hydrogen arrangement than glucose

Question 23

what is ribose in terms of its chains?

Answer 23

a 5 carbon chain with an aldehyde in linear form

Question 24

what is deoxyribose in terms of its chain?

Answer 24

a 5-carbon chain with an aldehyde in linear form and one less oxygen on carbon 2

Question 25

how does alpha differ from beta glucose in terms of their chains?

Answer 25

Alpha–glucose: The hydroxyl group at c1 is BELOW the plane of the ring down, down, up, down Beta – glucose: The hydroxyl group at c1 is ABOVE the plane of the ring up, down, up, down 50% chance of forming alpha or beta

Question 26

what is galactose hydroxyl format?

Answer 26

down, down, up, up

Question 27

what is fructose hydroxyl format?

Answer 27

starting from carbon 2 up, down, down

Question 28

What are disaccharides composed of? what are they bonded by?

Answer 28

Sugars containing two simple sugars attached to one another by covalent bonds called glycosidic linkages

Question 29

Which reaction forms disaccharides? Where do the H and OH come from

Answer 29

Formed via a condensation reaction (water removed). The H atoms come from a hydroxyl group on one sugar and the remaining –OH comes from a hydroxyl group on the adjacent sugar.

Question 30

what is maltose composed of? What is it's linkage? Where is maltose found in?

Answer 30

from grain, found in beer Two alpha – glucose molecules held together by a 1-4 glycosidic linkage

Question 31

what is sucrose composed of?

Answer 31

table sugar Alpha-glucose and fructose held together by a 1-2 glycosidic linkage

Question 32

what is lactose composed of? What is it's linkage? What is it found in?

Answer 32

found in milk Alpha – glucose and galactose held together by a 1-4 glycosidic linkage

Question 33

How is a disaccharide made? What are the sugar held together by? what are the three important examples?

Answer 33

The union of 2 monosaccharides in a condensation/dehydration reaction. The sugars are held together by a glycosidic linkage/bond. -sucrose, lactose, maltose

Question 34

what are polysaccharides composed of? what are they formed by? what are they broken apart by?

Answer 34

Several hundred to several thousand monosaccharide subunits held together by glycosidic linkages. The monosaccharide sugars are joined by condensation reactions or the polysaccharides are easily broken apart by hydrolysis.

Question 35

what are four examples of polysaccharides?

Answer 35

cellulose, chitin, starch, glycogen,

Question 36

what are isomers? what are examples (4)?

Answer 36

-Molecules with the same chemical formula but with a different arrangement of atoms in space -They also have different physical and chemical properties -alpha glucose, beta glucose, galactose, fructose with the molecular formula C6H12O6

Question 37

what is the structure of triglyceride? About how many carbons do fatty acid chains contain?

Answer 37

glycerol connected to one, two, or three fatty acids (16-18 carbons long)

Question 38

what is glycogen a polymer of? where is glycogen found? where is glycogen stored?

Answer 38

Polymer of alpha-glucose -found in animals -stored in the liver and muscles

Question 39

what is starch a polymer of? where is starch found? what is starch composed of?

Answer 39

Polymer of alpha-glucose -found in plants -Combination of 2 polymers: amylose & amylopectin

Question 40

what is cellulose a polymer of? where is cellulose found? what is a condition of cellulose?

Answer 40

-Polymer of beta-glucose -found in plant cell walls -un-digestible by humans, therefore, acts as roughage scraping intestinal walls.

Question 41

what is chitin a polymer of? what is chitin commonly found in?

Answer 41

A modified polymer of glucose with a group containing nitrogen at c2. -Common in insect and crustacean exoskeletons

Question 42

how is glycogen made? what are the types of bonds formed?

Answer 42

excess glucose molecules bond together to form glycogen. 1-4 glycosidic main chain linkages and 1-6 glycosidic branch point linkages.

Question 43

what linkages are in cellulose?

Answer 43

beta 1-4 glycosidic linkage

Question 44

what percentage of amylose makes up starch? what is amylose? what are the linkages in amylose? Is amylose soluble? what is its texture? (5)

Answer 44

-20% of starch, can range from 0-30% -Straight chain glucose polymer -1-4 glycosidic linkages of 300-1000 glucose molecules -Less soluble in water -More rigid and hard and used more regularly in cooking

Question 45

what percentage of amylopectin is in starch? what is amylopectin? what are amylopectin linkages? what are they soluble in? what does it form in hot water? what is its consistency? (6)

Answer 45

-80% of starch -Branched chain glucose polymer -1-4 glycosidic linkages on the main chain, 1-6 glycosidic linkages at the branch points, branch every 20-30 glucose molecules -More soluble in water, therefore more readily absorbed by the body -Forms a starch gel/paste in hot water -Softer consistency