AP Bio Midterm Review - Macromolecules

A macromolecule is found to have C,H,O,N, and S. Identify?

• Carbohydrate

• Lipid

• Nucleic Acid

• Protein

Answer explanation

All of the macromolecules have carbon (C), hydrogen (H), and oxygen (O). Nitrogen is found in proteins and nucleic acids. Sulfur is found in the R group of some amino acids. Proteins are the only macromolecule with C, H, O, N, and S

A macromolecule is found to have C,H, O, N, and P. Identify?

• Carbohydrate

• Lipid

• Nucleic Acid

• Protein

Answer explanation

All of the macromolecules have carbon (C), hydrogen (H), and oxygen (O). Nitrogen is found in proteins and nucleic acids. Phosphorous is found in nucleotides (and phospholipids) which is found in nucleic acids. Nucleic acids are the only macromolecule with C, H, O, N, and P.

What macromolecule also has phosphate? (Think of the cell membrane structure)

• Carbohydrates

• Nucleic Acids

• Lipids

• Proteins

Answer explanation

Note: lipids wasn't the answer earlier because they don't have a Nitrogen (and all the members don't have Phosphate)

Where is the Nitrogen found in proteins?

• In the carboxyl grou[

• In the amino group

• In the hydroxyl group

• In the phosphate group

Where is the nitrogen found in nucleic acids?

• Pentose sugar

• Nitrogenous base

• Phosphate group

• Hydroxyl group

Answer explanation

The Nitrogen is in the nitrogenous bases (A, T, C, G, U) that branch from the pentose sugar in each nucleotide (specifically the 1' BUT THAT’S NOT IMPORTANT)

How many valence electrons does Carbon have?

• 2

• 3

• 4

• 5

Answer explanation

Valence electrons are the electrons found in the outermost energy level. The first energy level can hold 2 electrons and the second energy level can hold 8 electrons. If you look at the periodic table, carbon has 6 electrons. There are 2 in the first level leaving 4 for the outermost energy level.

What type of bond does Carbon make other atoms?

• Covalent

• Hydrogen

• Ionic

• Van der Waals

Answer explanation

Carbon has four valence electrons (so it is equidistant from a complete valence shell). Due to this, carbon will share its valence electrons. Sharing valence electrons is due to covalent bonding.

Which of the following macromolecules include nitrogen?

• Carbohydrates & Lipids

• Lipids & Nucleic Acids

• Nucleic Acids & Proteins

• Proteins & Carbohydrates

Answer explanation

Nitrogen is

› found in the amine group of amino acids (which is protein’s monomer)

› found in the nitrogenous base of nucleotides (which is nucleic acid’s monomer)

Which of the following macromolecules has phosphate?

• Carbohydrate

• Fat

• Nucleic Acid

• Protein

Answer explanation

Phosphate is

› found in phospholipids which has a glycerol bound to one phosphate and two fatty acids

› found in nucleotides which is the monomer of nucleic acids

Which of the following macromolecules has sulfur?

• Carbohydrate

• Fat

• Nucleic Acid

• Protein

Answer explanation

Sulfur is found in the R group of some amino acids

(methionine and cysteine).