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Biology 112 > Molecules > Flashcards

Flashcards in Molecules Deck (24):
1

What are the six groups that are commonly attached to carbon atoms?

Hydroxyl, phosphate, sulfhydryl, amino, carbonyl and carboxyl.

2

How do we form polymers from monomers?

Polymerization through condensation reaction. A reaction that cause the hydrogen on the end of the polymer to interact with the hydroxide on the monomer and produce a water molecule.

3

What is hydrolysis?

Breaking down a polymer, water in, monomer out.

4

What comprises an amino acid?

Carbon, hydrogen, an amino group, a carboxyl group and an R side chain.

5

What is the difference between non-ionized form of amino acid and the ionized form?

Ionized form has an extra hydrogen in the amino group and an oxygen in the carboxyl group instead of hydroxide. Causes the molecule to be polar.

6

What type of side chain is most soluble in water?

Electrically charged side chains form hydrogen bonds and are highly soluble. Polar side chains are soluble in water and can form hydrogen bonds as well.

7

Why doesn't proline show up in alpha helixes?

Proline can not form the necessary hydrogen bonds resulting in a kink. Also doesn't show up in beta pleated sheets.

8

What is an isotope?

An atom of an element with a variant amount of neutrons.8

9

Do solutions with the same pH have the same amount of water molecules? If not why?

No. Solutions can have a wide variety of solute amounts which can vary the amount of water molecules.

10

Why do the polymers of cellulose and starch differ?

The differ in their glycosidic linkages. Starch is made up of alpha-glucose linkages whereas cellulose is made up of beta-glucose and the orientation of the glucose alternates.

11

Is alpha-glucose linkages or beta glucose linkages more stable?

Beta glucose form more stable structures because it is very linear. Alpha glucose is less stable as it is commonly branched and therefore does not form as tight bonds.

12

What is the only covalent bond in tertiary protein structure?

The only covalent bond is made from a sulfur containing side group SH.

13

Why do alpha glucose and beta glucose form different ring forms.

The two different forms are formed by identical glucose molecules that are joined at c1 to c5, the only difference is that c1 becomes asymmetric upon closure meaning that the newly formed hydroxide can point either up or down.

14

In what direction are proteins formed and at what terminus is the next bond made?

Proteins are formed from N to C therefore the next monomer to be added will be added at its N terminus to the polymers c terminus.

15

What makes up a triglyceride?

3 fatty acids covalently bonded to a glycerol. Has three ester linkages.

16

What makes up a phospholipid?

2 fatty acids attached to a glycerol which is attached to a phosphate group. The phosphate group is hydrophilic.

17

What stabilizes the secondary protein structure?

Hydrogen bonding between the peptide backbone. Hydrogen bonding between side chains does not contribute to secondary structure.

18

What causes a fat to be classified as unsaturated?

Missing a hydrogen causing a double bond along the fatty acid. The double bond causes a kink and the phospholipid bilayer becomes for permeable.

19

What position on a nucleotide would a phosphate group from another nucleotide bond to?

3'

20

Is the molecule C16H22O2 a lipid, a carbohydrate, a hydrocarbon, a nucleic acid or a protein?

Lipid

21

What is a nucleotide?

A nucleotide is the base unit of DNA.

22

What are the three components that make up a nucleotide?

A phospate, a base (ATGCU) and a 5 carbon sugar.

23

What is a fatty acid made out of?

Carboxyl group, hydrocarbon chain that is saturated with hydrogen

24

What are the two categories of nucleotides and which nucleotides are in each?

Pyrimidines and purines. Purines are bigger (2 rings) and contain adenine and guanine. Pyrimidines only have 1 ring and contain cytosine, uracil and thymine.