AP Biology Unit 1 Review: Chemistry of Life

Flashcards covering essential chemistry and biology topics for AP Biology Unit 1 review, including water properties, macromolecules, nucleic acids, and protein structure.

What are the three subatomic particles that make up an element, and what are their charges and locations?

Protons have a positive charge and are in the nucleus; neutrons have a neutral charge and are in the nucleus; electrons have a negative charge and orbit the nucleus in electron orbitals.

What determines the reactivity of an element?

Valence electrons, which are the electrons located in the outermost orbital.

What is electronegativity?

An atom's ability to attract electrons toward itself.

How is an ionic bond formed?

Through the transfer of electrons between elements due to the attraction between different charges.

What is the difference between a non-polar covalent bond and a polar covalent bond?

In a non-polar covalent bond, elements share electrons equally because they have the same electronegativity. In a polar covalent bond, electrons are shared unequally due to a highly electronegative element, resulting in partial positive and negative charges.

Which four elements mentioned in the lecture are highly electronegative?

Nitrogen, oxygen, fluorine, and chlorine.

How do hydrogen bonds form between water molecules?

The negatively charged oxygen side of one water molecule attracts the positively charged hydrogen side of another water molecule.

Why does water have a high specific heat capacity?

Because a large amount of energy is required to break the hydrogen bonds between water molecules before its temperature can change.

How does sweating cool the body using water's high heat of vaporization?

As water evaporates from the skin, it absorbs thermal energy and carries it away from the body.

What is the difference between cohesion and adhesion?

Cohesion is the attraction of a molecule to itself, whereas adhesion is the attraction of a molecule to other molecules.

How does cohesion produce surface tension in water?

Hydrogen bonds formed at the water's surface hold the water molecules together, creating a surface tension that allows small organisms like water striders to stay on top of the water.

Which elements are present in all four main macromolecules?

Carbon, hydrogen, and oxygen.

Which macromolecules contain nitrogen, and which contain phosphorus?

Nitrogen is found in nucleic acids and proteins; phosphorus is found in nucleic acids and lipids.

What occurs during a dehydration synthesis reaction?

Water is removed to join two molecules together, taking an -OH group from one molecule and an -H atom from another to form water.

What is hydrolysis?

A process that uses water to break a covalent bond between monomers ('hydro' meaning water and 'lysis' meaning to cut).

What are the monomers and polymers of carbohydrates?

The monomer is a monosaccharide and the polymer is a polysaccharide.

What are the specific functions of glycogen, starch, and cellulose?

Glycogen stores energy in animals and fungi; starch stores energy in plants; cellulose forms the cell walls of plants.

Why are saturated fatty acids solid at room temperature while unsaturated fatty acids are liquid?

Saturated fatty acids have only single carbon-carbon bonds, forming straight chains that pack tightly together. Unsaturated fatty acids contain at least one double carbon-carbon bond, causing kinks in the chain that prevent tight packing.

What are four functions of lipids in the body?

Phospholipids form cell membranes, fats store energy and provide insulation, steroids act as hormones, and cholesterol provides structural support in animal cell membranes.

What three components make up a nucleotide monomer?

A 5-carbon sugar, a phosphate group, and a nitrogenous base.

To which end of a nucleic acid chain are new nucleotides added?

New nucleotides are always added to the $3'$ hydroxyl end via dehydration synthesis.

What base pairing rules apply to DNA and RNA?

In DNA, adenine pairs with thymine ($A-T$) and cytosine pairs with guanine ($C-G$). In RNA, adenine pairs with uracil ($A-U$) instead of thymine.

What are three structural differences between DNA and RNA?

DNA has deoxyribose sugar, contains thymine, and is double-stranded. RNA has ribose sugar, contains uracil, and is single-stranded.

What components make up the basic structure of an amino acid?

A central carbon atom attached to a carboxyl group, an amine group, an R group, and a hydrogen atom.

Which part of an amino acid determines its chemical properties?

The R group (side chain).

What are the four levels of protein structure?

Primary structure (amino acid sequence), secondary structure (local folding into alpha helices and beta pleated sheets), tertiary structure (3D shape from R group interactions), and quaternary structure (joining of multiple polypeptide chains).