Chapter 2 Part II- Water And Life

Question 1

Chemical structure of water

Answer 1

Hydrogen and oxygen are connected by polar covalent bonds

Weak electrical attractions btw other h2o molecules

-hydrogen bonds

Question 2

Characteristics of water

Answer 2

• Most abundant molecule
• Polar solvent- many substances can dissolve into it
• Cohesive and adhesive (stick together and to other substances)
• Regulates temperature
• Less dense as a solid than as a liquid

Question 3

Hydrophilic

Answer 3

Molecules that interact with h2o

Water loving

Question 4

Hydrophobic

Answer 4

Molecules that do not interact with water

Water fearing

Question 5

Acid

Answer 5

A molecule that adds hydrogen to a solution

Question 6

Base

Answer 6

A molecule that either releases hydroxide (OH-) ions into a solution or removes hydrogen ions

Question 7

pH scale

Answer 7

Measure of the concentration of H+ in a solution

pH 7 (neutral)
pH less than 7 (acidic)
pH greater than 7 (basic)

Question 8

Homeostasis

Answer 8

Maintaining the proper balance btw acid and base

Question 9

Buffers

Answer 9

Minimize changes in pH

Question 10

Organic molecules

Answer 10

Generate life’s form and function

Carbon based

Question 11

Macromolecules

Answer 11

Large molecules made up of smaller subunits called monomers

Question 12

Dehydration reactions

Answer 12

Formation of covalent bond between monomers by loss of water

Used to store energy

Question 13

Hydrolysis

Answer 13

Splitting a macromolecule by adding water

Used to release energy

Question 14

4 main families of macromolecules

Answer 14

Carbohydrates
Proteins
Lipids
Nucleic acids

Question 15

Carbohydrates

Answer 15

Monomers = simple sugars
Functions= immediate supply of energy and storage 
Examples= glucose, sucrose, lactose

Question 16

Proteins

Answer 16

Monomers= amino acids
Functions= structural basis of all organisms, biological catalysts, antibodies, oxygen transport, regulate what gets in and out of cells
Examples= hemoglobin, DNA polymerase, collagen

Question 17

Peptide bonds

Answer 17

Bond between two amino acids

Question 18

4 levels of protein structure

Answer 18

Primary, secondary, tertiary, quaternary

Question 19

Lipids

Answer 19

Monomers= glycerol, fatty acids
Functions= long term energy storage, structure of cell membrane
Examples= fats, oils, phospholipids, steroids, waxes

Question 20

Nucleic acids

Answer 20

Monomers= nucleotides
Functions= information storage (heredity), directs cellular activity
Examples= DNA and RNA