Unit 1 - Exam Review

Question 1

1.1 Explain ionic, covalent, and polar covalent

Question 2

1.1 Explain intermolecular forces

Answer 2

London dispersion - every atom has them, weakest imf
Dipole-Dipole - polar molecules have them, intermediate imf
H-Bonds - molecules with a + H and - N O F

Question 3

1.1 Water’s 3 unique properties

Answer 3

1. Water clings (to itself or to a surface)
2. Density (less dense when solid therefore ice floats)
3. Water absorbs heat (cooling sweat effect and internal temp maintained)

Question 4

1.1 Explain molecular polarity

Answer 4

The polarity of a molecule depends not only on the polarity of bonds but also on the 3D VSEPR shape. Bonds cancel out when evenly spaced.

Question 5

1.1 What is a neutralization rxn

Answer 5

The reaction of an acid and a base to produce water and a salt

Question 6

1.1 Define buffers

Answer 6

Chemical systems containing a substance that can donate H ions when they are required and containing a substance that can remove H ions when there are too many in a solution

Question 7

1.2 Name the 6 main functional groups + uses and formula

Answer 7

1. Hydroxyl (OH) - Alcohol
2. Carboxyl (COOH) - Acids
3. Amino (NH2) - Bases
4. Sulfhydryl (SH) - Rubber
5. Phosphate (PO4) - ATP
6. Carbonyl Ketone (=O in middle) - N/A
7. Carbonyl Aldehyde (=O) - N/A

Question 8

1.2 Name and explain the structure and function of the 4 major macromolecules

Carbs (5 types, functional group)
Proteins (types of structure)
Lipids (3 types, rxn to water)
Nucleic acid (shape)

Answer 8

Carbohydrates - Made of simple sugars (CHO) with a carbonyl group. Used as a source of energy. Starch, cellulose, amylopectin, chitin, glycogen.

Proteins - Made of amino acid polymers folded into 3D shapes. Used for structure, enzymes, hormones, etc. Primary (linear), secondary (a helix, b pleated), tertiary (more folds held together by H+), quaternary (multiple amino acid chains).

Lipids - Made of triacylglycerols (containing three fatty acids attached to a single molecule of glycerol), phospholipid (hydrophilic head and 2 hydrophobic tails), and waxes (long-chain fatty acid + alcohol). Used as energy storage. Hydrophobic.

Nucleic Acids - Made of nucleotides. Used to store hereditary information. Antiparallel double helix

Question 9

1.2 Condensation and hydrolysis reactions

Answer 9

Condensation - Removal of H2O to attach molecules
Hydrolysis - Addition of H2O to break molecules

Question 10

1.3 Name 3 types of energy

Answer 10

Kinetic: energy of movement
Potential: stored energy
Free Energy: energy that can do useful work

Question 11

1.3 Define metabolism, catabolism, and anabolism

Answer 11

Met: Sum of metabolic rxns
Cat: Breaking things down
Ana: Building things up

Question 12

1.3 Explain entropy

Answer 12

The measurement of disorder in a system. The symbol is S. The universe favors an increase in entropy.
-△G is spontaneous
+△G is non spontaneous

Question 13

1.3 Laws of thermodynamics

Answer 13

1st Energy cannot be created or destroyed but can be transferred from one form to another.

2nd Every time energy is converted into another form, some energy becomes unusable.

Question 14

1.3 Exergonic vs Endergonic + examples

Answer 14

Exer - Release energy, spontaneous, -△G, cellular resp
Ender - Requires energy, non spontaneous, +△G, photosynthesis

Question 15

1.4 Enzymes – use + optimal working conditions

Answer 15

Protein catalysts that speed up processes by lowering the activation energy. pH and temp must be optimal or they will be denatured.

Question 16

1.4 Allosteric regulation and feedback inhibition

Answer 16

Allosteric regulation: activators hold enzymes open, and inhibitors hold them closed. The allosteric site is not the active site.

Feedback inhibition: a product of a later step inhibits an earlier step

Question 17

1.5 Methods of transport – Passive versus active

Answer 17

Passive: transport that occurs with the concentration gradient that requires no extra energy

Active: transport that occurs against the concentration gradient that requires vesicles

Question 18

1.5 Passive – simple diffusion, facilitated diffusion, osmosis

Answer 18

Simple: Movement of particles from an area of higher concentration to one of lower

Facilitated: The use of protein transport molecules to facilitate the movement of large or polar molecules into the cell, using the concentration gradient, NA+ K+ pump.

Osmosis: Diffusion of water across a selectively permeable membrane
-Hypertonic solution - solutes > cytoplasm
-Isotonic solution - solutes = cytoplasm
-Hypotonic solution - solutes < cytoplasm

Question 19

1.5 Active – endocytosis and exocytosis

Answer 19

Endocytosis: movement of large material into the cell
-phagocytosis (cell eating), pinocytosis (cell drinking), receptor-mediated (hormones)

Exocytosis: movement of large material out of the cell
-Proteins and hormones are surrounded by a membrane at the Golgi complex and a vesicle is formed. The vesicle fuses with the cell membrane and the protein is expelled from the cell.

Question 20

1.5 Structure and function of the cell membrane and the Fluid Mosaic model + 2 main parts

Answer 20

The fluid component refers to the fact that the membrane is not rigid.

Phospholipids: make up the membrane with a hydrophilic head and hydrophobic tails
Proteins: facilitate movement of material through the membrane, enzymes, hormone receptors