Chapter 2: The Chemistry Of Life

Question 1

Matter

Answer 1

Anything that has mass and occupies space

Question 2

Element

Answer 2

A pure substance with unique physical and chemical properties
Can not be broken down into other substances

Question 3

Atom

Answer 3

Smallest unit of an element

Question 4

Protons, Neutrons, and Electrons

Answer 4

P = positive charge
E = negative charge (floating around - orbit the nucleus in electron shells)
N = lack an electrical charge

Question 5

Atomic nucleus

Answer 5

If it is positively charges it contains one or more protons and usually the same number of neutrons
Different than cellular nucleus

Question 6

Atomic number

Answer 6

Represents the number of protons in an atom

Question 7

Atomic mass number

Answer 7

Total number of protons and neutrons in an atom (electrons don’t count when adding up mass)

Question 8

If you change the protons…

Answer 8

Changes the type of element

Question 9

If you change the neutrons…

Answer 9

Slightly changes the chemical properties

ISOTOPE

Question 10

If you change the electrons…

Answer 10

Changes the overall atomic charge

Question 11

Ions

Answer 11

Atoms of an element that carry a net charge

Question 12

Combinations of atoms make…

Answer 12

Molecules

Can’t be of the same lament: O(2)

Question 13

Biomolecules

Answer 13

Carbon based
Molecules found in living cells
Subset of organic molecules

Question 14

Covalent bonds

Answer 14

Created by the sharing of electrons between constituent atoms
Strongest bond
Single bond exists when two atoms share a PAIR of electrons
Double bond exists with when two atoms share TWO PAIRS of electrons

Question 15

Covalent bonds - polar vs non-polar

Answer 15

Polar = has a net electrical charge, if molecule contains oxygen or nitrogen combined with any other element (unequal sharing)  
Non-polar = no net electrical charge (equal sharing)

Question 16

Ionic bonds

Answer 16

Weak bond
Not sharing - stealing of electrons
EX: Salt
Atoms or molecules that have gained or lost electrons and have a full unit of electrical charge are called ions

Question 17

Water property: polar

Answer 17

A water molecule is 2 hydrogen atoms and one oxygen Aton held together by covalent bonds
Polarity of water is what gives water its unique properties

Question 18

Water property: ice floats and acts as an insulator

Answer 18

Water molecules are farther apart in ice than in water, causing ice to be less dense and to float
Liquid has more molecules than ice
As water cools, the hydrogen bonds form in an orderly pattern

Question 19

Water property: water is an excellent solvent

Answer 19

Things dissolve into it - like salt or sugar (these two things would be salutes)
Water inserts itself in polar molecules causing it to dissolve
Hydrophobic molecules are typically non-polar and do NOT associate with water
Hydrophilic molecules are polar and interact/form hydrogen bonds with water

Question 20

Water property: water moderates temperature swings

Answer 20

Water can absorb and release large amounts of heat
High boiling point
High heat capacity of water in cells serves to protect them from changes in internal temperatures

Question 21

Water property: the evaporation of water has a cooling effect

Answer 21

When water molecules are heated, they become energetic enough to escape their hydrogen bonds as water vapor in the process called evaporation

Question 22

Water property: cohesion and adhesion

Answer 22

Cohesion: the hydrogen bonding between water molecules (molecules attracted to themselves) Creates surface tension
Adhesion: the hydrogen bonding between water and other molecules

Question 23

The pH scale

Answer 23

Measures the concentration of hydrogen ions
1(strongly acidic) - 14 (strongly basic)
Acid releases hydrogen ions
Base accepts hydrogen ions
The higher the number on the pH scale, the fewer the number of protons in the solution
*Each number up or down is a difference of 10 times

Question 24

Chemical reactions

Answer 24

Rearrangements of atoms
Breaking and forming bonds
Reactants > products
Atoms are never destroyed or created

Question 25

Chemical reactions can be affected by...

Answer 25

PH Temperature Salt concentration

Question 26

Organic molecules

Answer 26

Molecule that contains at least one carbon-hydrogen bond OR nitrogen-hydrogen bond

Question 27

Biomolecules

Answer 27

Have a carbon framework Monomers vocal entry one to each other to form polymers They are polymers of carbon-based monomers

Question 28

Biomolecules: Carbohydrates

Answer 28

AKA sugars or sac arises Used for energy storage (glucose, sucrose) and structural support (cellulose in plants) Monomer: monosaccharide - glucose and ribose Polymer: polysaccharide - starch, cellulose, glycogen

Question 29

Biomolecules: proteins

Answer 29

Functions: structure (hold cells together - collagen), transport (move molecules in a cell), cell signaling, enzymatic reactions Monomer: amino acids (consist of a functional group attached to a R group) Polymer: polypeptide/protein

Question 30

Protein structure - folding

Answer 30

Primary: amino acids in a string Secondary: bend that string and hold it in place with hydrogen bonds (beta-pleated sheet) Tertiary: covalent and hydrogen bonds between portions that are far away from each other Quarternary: more than one protein subunit bonded together - 2 tertiary structures together

Question 31

Protein folding

Answer 31

Basic folded structure depends on sequence of amino acids

Question 32

Denature get proteins

Answer 32

Destruction of a proteins 3D shape, resulting in a loss of protein activity/function Things that effect it: pH, temperature, salt concentration

Question 33

Biomolecules: lipids

Answer 33

Functions: long-term energy storage, plasma membrane, cell signaling (hormones) Mostly hydrophobic/non-polar Monomer: fatty acids (no polar hydrocarbon chains attached to a hydrophilic/polar head) Polymer: fats/oils

Question 34

Animals store surplus energy as...

Answer 34

Triglycerides - 3 fatty acid molecules bonded to a glycerol molecule

Question 35

Saturated fatty acids

Answer 35

Fats Solid at room temp Butter

Question 36

Unsaturated fatty acids

Answer 36

Liquid at room temp Vegetable oils Plants use these

Question 37

Phospholipids

Answer 37

Make up cell membrane - phospholipid bilayer | They are 2 hydrophobic fatty acid tails (non-polar) bonded to hydrophilic heads (polar)

Question 38

Biomolecules: Nucleic acids

Answer 38

Used for information storage and transformation, heredity, energy transfer EX: DNA(double-stranded), RNA(single stranded) Monomers: nucleotides (made up of a nitrogen base, sugar, and phosphate group) Polymer: nucleus acids