AP Bio Quiz: Macromolecules

What are polymers?

a long molecule consisting of many similar or identical building blocks linked by covalent bonds

What are monomers?

repeating units that serve as the building blocks of a polymer, smaller molecules

What are enzymes?

specialized macromolecules (usually proteins) that speed up chemical reactions

Dehydration reaction

monomers are connected by a reaction in which two molecules are covalently bonded to each other, loss of water molecules (bond forms between 2 monomers, each contributes part of water molecule released during reaction, -OH/-H, MAKES POLYMER)

Hydrolysis

process that is essentially revers of dehydration reaction, POLYMERS DISASSEMBLED TO MONOMERS, (bond between monomers broken by addition of water molecule, hydrogen to one, hydroxyl group to adjacent)

Monomer form for carbohydrates, nucleic acid, protein, and lipids

carbohydrates: monosaccarides

proteins: amino acids

lipids: fatty acid/glycerol

nucleic acids: nucleotides

What kind of bond forms between two monosaccharides to form a disaccharide or polysaccharide?

a covalent bond

What is the function of starch, glycogen and cellulose? What type of macromolecules are these?

Starch: to convert into glucose for energy

Glycogen: the secondary long-term energy storage, with the primary energy stores being fats held in adipose tissue

Cellulose: major component of tough cell walls that surround plant cells, and is what makes plant stems, leaves, and branches so strong

(ALL OF THESE ARE CARBOHYDRATES)

Know the difference between an unsaturated fatty acid and saturated fatty acid. Which one has a kink in the chain? Which one is solid at room temperature? Which one is liquid at room temperature?

Unsaturated fatty acid: have one or more double bonds between carbon atoms.

Saturated fatty acid: have no double bonds between the individual carbon atoms of the fatty acid chain.

• Unsaturated fatty acids have a kink in the chain

• Saturated fatty acids are solid at room temperature

• Unsaturated fatty acids are liquid at room temperature.

Know how to identify a steroid

Steroids can be defined by their chemical structure. We see that steroids are organic compounds that contain four rings of carbon atoms. Specifically, we see that all steroids have three 6-sided carbon rings and one 5-sided carbon ring.

What kind of bond forms between amino acids?

peptide bonds

What is common between all amino acids? What is different?

All amino acids have a two carbon bond. The differences are in the R-groups where different functional groups in the r-groups of each amino acid causes them to have different properties (ie. some are acidic and some are basic)

What are the 4 levels of protein structure (this was not gone over in class, see page 55-57 in your text). Be able to describe them.

Primary Structure - describes the unique order in which amino acids are linked together to form a protein. Proteins are constructed from a set of 20 amino acids.

Secondary Structure - refers to the coiling or folding of a polypeptide chain that gives the protein its 3-D shape. There are two types of secondary structures observed in proteins. One type is the alpha helix structure. This structure resembles a coiled spring and is secured by hydrogen bonding in the polypeptide chain. The second type of secondary structure in proteins is the beta pleated sheet. This structure appears to be folded or pleated and is held together by hydrogen bonding between polypeptide units of the folded chain that lie adjacent to one another.

Tertiary Structure - refers to the comprehensive 3-D structure of the polypeptide chain of a protein. There are several types of bonds and forces that hold a protein in its tertiary structure. Hydrophobic interactions greatly contribute to the folding and shaping of a protein. Hydrogen bonding in the polypeptide chain and between amino acid "R" groups helps to stabilize protein structure by holding the protein in the shape established by the hydrophobic interactions.

Quaternary Structure - refers to the structure of a protein macromolecule formed by interactions between multiple polypeptide chains. Each polypeptide chain is referred to as a subunit. Proteins with quaternary structure may consist of more than one of the same type of protein subunit.

What happens when a protein is heated? What does denaturation mean?

If protein molecules are heated too much they "denature". This means they lose their shape and "fall apart".

Denaturation: a process in which proteins or nucleic acids lose the quaternary structure, tertiary structure and secondary structure which is present in their native state, by application of some external stress or compound such as a strong acid or base (or other substance)

What components make up a nucleotide? What is the difference between a pyrimidine and a purine?

What makes up a nucleotide:

1) a five carbon ribose sugar

2) a phosphate molecule

3) one of four nitrogenous bases: adenine, guanine, cytosine or uracil.

Pyrimidine: a colorless crystalline compound with basic properties.

Purine: a colorless crystalline compound with basic properties, forming uric acid on oxidation.

What kind of sugar is found in DNA? What kind of sugar is found in RNA?

DNA: deoxyribose

RNA: ribose