2.2 Linkages in Biological Molecules Flashcards
what are the monosaccharides of carbohydrates?
glucose, fructose, galactose
what are four different types of lipids?
fats, phospholipids, steroids, waxes
what makes lipids unique compared to other macromolecules?
there subunits do not repeat
what is the subunit of proteins?
Proteins are amino acids
What are the polypeptides? What do they undergo before turning into a protein?
polypeptides are long chains of amino acids undergo specific folding before it becomes a functional protein
what are the three parts of nucleic acids?
nitrogen base, 5-carbon sugar such as a ribose or deoxyribose, PO4 group
what macromolecules are hydroxyl groups found? (4)
carbs, fats (glycerol), proteins, nucleic acids
where are carbonyl groups found?
in carbohydrates in linear form such as aldehydes and ketones
where are amino groups found?
in proteins
where are phosphate groups found?
in phospholipids, DNA, RNA, ATP
where are thiol or sulfhydryl groups found?
amino acids, or proteins
how is a glycosidic bond formed?
a bond formed between the hydroxyl groups on two adjacent sugars
how is an ester linkage formed?
a bond formed between the hydroxyl of glycerol and a carboxyl group of the fatty acid to form triglyceride
how is an amide linkage formed? what is this also called?
a bond formed between the carboxyl on an amino acid and an amine on an adjacent amino acid also called a peptide bond
how is a phosphodiester bond formed?
forms between the hydroxyl on one nucleotide and the phosphate on an adjacent nucleotide
why are carbohydrates important (3)? b,c,e
-building material
-cell surface markers
-important energy source for organisms
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?
-1:2:1 ratio CHO
-chemical formula is CnH2nOn
-monosaccharides, oligosaccharides, polysaccharides
-suffix “os” glucose, sucrose
what are monosaccharides and what are they important for? what form are these molecules most often found as?
-simple sugar molecules important for energy transfer in the blood
-they are most often found as pentose or hexose rings
what are important examples of polysaccharides 5?
glucose, fructose, galactose, ribose, deoxyribose sugars
what is glucose in terms of it’s chain? what is it found in?
-a six-carbon chain with an aldehyde in linear form
-found in plants and animals
what is fructose in terms of it’s chains?
-a six-carbon chain with ketone in linear form
what is galactose in terms of it’s chain?
-a six-carbon chain with an aldehyde in linear form but a different hydrogen arrangement than glucose
what is ribose in terms of its chains?
a 5 carbon chain with an aldehyde in linear form
what is deoxyribose in terms of its chain?
a 5-carbon chain with an aldehyde in linear form and one less oxygen on carbon 2
how does alpha differ from beta glucose in terms of their chains?
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
what is galactose hydroxyl format?
down, down, up, up
what is fructose hydroxyl format?
starting from carbon 2 up, down, down
What are disaccharides composed of? what are they bonded by?
Sugars containing two simple sugars attached to one another by covalent bonds called glycosidic linkages
Which reaction forms disaccharides? Where do the H and OH come from
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.
what is maltose composed of? What is it’s linkage? Where is maltose found in?
from grain, found in beer
Two alpha – glucose molecules held together by a 1-4 glycosidic linkage
what is sucrose composed of?
table sugar
Alpha-glucose and fructose held together by a 1-2 glycosidic linkage
what is lactose composed of? What is it’s linkage? What is it found in?
found in milk
Alpha – glucose and galactose held together by a 1-4 glycosidic linkage
How is a disaccharide made? What are the sugar held together by? what are the three important examples?
The union of 2 monosaccharides in a condensation/dehydration reaction. The sugars are held together by a glycosidic linkage/bond.
-sucrose, lactose, maltose
what are polysaccharides composed of? what are they formed by? what are they broken apart by?
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.
what are four examples of polysaccharides?
cellulose, chitin, starch, glycogen,
what are isomers? what are examples (4)?
-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
what is the structure of triglyceride? About how many carbons do fatty acid chains contain?
glycerol connected to one, two, or three fatty acids (16-18 carbons long)
what is glycogen a polymer of? where is glycogen found? where is glycogen stored?
Polymer of alpha-glucose
-found in animals
-stored in the liver and muscles
what is starch a polymer of? where is starch found? what is starch composed of?
Polymer of alpha-glucose
-found in plants
-Combination of 2 polymers: amylose & amylopectin
what is cellulose a polymer of? where is cellulose found? what is a condition of cellulose?
-Polymer of beta-glucose
-found in plant cell walls
-un-digestible by humans, therefore, acts as roughage scraping intestinal walls.
what is chitin a polymer of? what is chitin commonly found in?
A modified polymer of glucose with a group containing nitrogen at c2.
-Common in insect and crustacean exoskeletons
how is glycogen made? what are the types of bonds formed?
excess glucose molecules bond together to form glycogen. 1-4 glycosidic main chain linkages and 1-6 glycosidic branch point linkages.
what linkages are in cellulose?
beta 1-4 glycosidic linkage
what percentage of amylose makes up starch? what is amylose? what are the linkages in amylose? Is amylose soluble? what is its texture? (5)
-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
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)
-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
