Test 1 - Ch. 2 - Chemistry of Life

Question 1

matter

what is weight?

Answer 1

anything that has mass and occupies space

weight is mass + the effects of gravity

Question 2

3 states of matter

Answer 2

solid - definite shape and volume
liquid - changeable shape w definite volume
gas - changeable shape and volume

Question 3

energy

Answer 3

the capacity to do work or put matter into motion

Question 4

kinetic energy

Answer 4

energy in action

Question 5

potential energy

Answer 5

stored (inactive) energy

Question 6

chemical energy

Answer 6

stored in bonds of chemical substance

Question 7

electrical energy

Answer 7

results from movement of charged particles

Question 8

mechanical energy

Answer 8

directly involved in moving matter

Question 9

radiant/electromagnetic energy

Answer 9

travels in waves (heat or light energy)

Question 10

energy conversion

Answer 10

energy can be changed from one form to another
however inefficient because some energy is lot as say heat

Question 11

elements

Answer 11

substances that cannot be broken down into simpler substances by ordinary chemical methods

Question 12

what four elements make up 96% of body

Answer 12

carbon, oxygen, hydrogen, and nitrogen

Question 13

molecule

Answer 13

general term for 2 or more atoms bonded together

Question 14

compound

Answer 14

specific molecule that has 2 or more DIFF kinds of atoms bonded

Question 15

mixtures

Answer 15

two or more components that are physically intermixed

Question 16

solutions

Answer 16

homogeneous mixtures where particles are evenly distributed throughout

Question 17

solvent and solute

Answer 17

solvent - substance in greatest amount (usually liquid ex. water)
solute - substance disolved in solvent

Question 18

3 concentrations of solutions

Answer 18

1. percent of solute in total solution (10 parts salt 90 parts water)
2. milligrams per deciliter mg/dl
3. molarity (number of moles of solute per liter of solvent)

Question 19

colloids

Answer 19

aka emulsions are heterogeneous mixtures, meaning that particles are not evenly distributed
- can see large particles but do NOT settle out
ex. jello

Question 20

suspensions

Answer 20

heterogeneous mixtures that contain large, visible solutes that do settle out
ex. water and sand, or blood

Question 21

ionic bond

Answer 21

the transfer of valence shell electrons from one atom to another resulting in ions

Question 22

ions (anion and cation)

Answer 22

ions - atoms that have gained or lost electrons and become charged

anion - negative charge
cation - positive charge

Question 23

covalent bond

Answer 23

formed by sharing 2 or more valence shell electrons between 2 atoms

share 2 - single bond share 4 - double bond share 6 - triple bond

Question 24

nonpolar and polar covalent bonds

Answer 24

nonpolar - equal sharing of electrons between atoms (electrically balanced)
polar - unequal sharing of electrons between 2 atoms (electrically polar)

Question 25

hydrogen bonds

Answer 25

attractive force between electropositive hydrogen of one molecule and an electronegative atom - not true bond, more of weak magnetic attraction

Question 26

chemical reaction

Answer 26

occur when chemical bonds are formed, rearranged, or broken

Question 27

reactants and products of chemical reactions

Answer 27

reactants - substances entering into reaction together product - resulting chemical end products

Question 28

synthesis reactions

Answer 28

combination reactions involving atoms or molecules combining to form larger more complex molecule anabolic (building process)

Question 29

decomposition reactions

Answer 29

involve the breakdown of a molecule into smaller molecules catabolic (bond breaking)

Question 30

exchange reactions

Answer 30

also called displacement reactions, involve both synthesis and decomposition, bonds made and broken

Question 31

in living systems, exchange reactions are also known as...

Answer 31

reduction - oxidation reactions or redox reactions - atoms are reduced when they gain electrons and oxidized when they lose electrons

Question 32

exergonic reactions

Answer 32

result in a release of energy (give off energy) products have less potential energy than reactants ex. catabolic and oxidative reactions

Question 33

endergonic reactions

Answer 33

result in a net absorption of energy (use energy) products have more potential energy than reactants ex. anabolic reactions

Question 34

how can the rate of chemical reactions be affected

Answer 34

temp - increased temps increased rate concentration of reactants - increased concentration increased rate particle size - smaller particles increased rate catalysts

Question 35

catalysts

Answer 35

increased rate of reaction w/o being chemically changed or becoming part of the product

Question 36

enzyms

Answer 36

biological catalysts

Question 37

inorganic compound

Answer 37

compound that does not contain carbon ex. water, salts, many acids and bases

Question 38

organic compound

Answer 38

compound containing carbon, usually large and covalently bonded ex. carbs, fats, proteins, nucleic acids

Question 39

water - biochem

Answer 39

the most abundant inorganic compound 60 to 80% of the volume of living cells

Question 40

salts

Answer 40

ionic compounds that dissociate into separate ions in water (into cations and anions)

Question 41

electrolytes

Answer 41

ions that can conduct electrical currents in solution

Question 42

acids

Answer 42

proton donors, RELEASE hydrogen ions, bare protons (have no electrons) in solution important acid - hydrochloric acid (HCl)

Question 43

bases

Answer 43

proton acceptors, PICK UP hydrogen ions, releases a hydroxyl ion important base - ammonia (NH3)

Question 44

pH scale

Answer 44

measurement of the concentration of hydrogen ions in solution. more hydrogen ions more acidic acids: 0 - 6.99 neutrals: 7 (equal number of H+ and OH- ions) bases: 7.01 - 14

Question 45

neutralization reaction

Answer 45

acids and bases are mixed together - displacement reaction occurs, forming water and salt

Question 46

buffers

Answer 46

resist abrupt and large swings in pH and can covert strong acids or bases into weak ones - can release hydrogen ions if pH rises - can bind hydrogen ions if pH falls

Question 47

carbohydrates

Answer 47

sugars and starches containing C, H, and O -monosaccharides -disaccharides -polysaccharides

Question 48

monosaccharides

Answer 48

the monomers of carbohydrates - simple sugars containing 3 to 7 carbon atoms - ex. glucose and deoxyribose

Question 49

disaccharides

Answer 49

double sugars formed by dehydration synthesis of 2 monosaccharides - too large to pass through cell membrane ex. sucrose and lactose

Question 50

polysaccharides

Answer 50

polymers of monosaccharides - formed by dehydration synthesis of many monomers - not soluble ex. starch and glycogen

Question 51

lipids

Answer 51

contain C, H, O, (but less than in carbohydrates) and sometimes P - insoluble in water

Question 52

triglycerides

Answer 52

lipid that is called a fat when slid and oil when liquid - composed of 3 fatty acids bonded to a glycerol molecule by dehydration synthesis main functions - energy storage, insulation, and protection

Question 53

saturated fatty acids

Answer 53

can compose triglycerides - all carbons are linked via single covalent bonds, resulting in a molecule with the max amount of H atoms it can hold (saturated) create linear molecules which can pack closely together forming a solid ex. butter

Question 54

unsaturated fatty acids

Answer 54

can compose triglycerides - one or more carbons are linked via double bonds. resulting in reduced H atoms (unsaturated) double bonds cause kink in the fatty acid so they cannot pack together closely resulting in liquid form at room temp ex. olive oil

Question 55

trans fats

Answer 55

modified unsaturated fatty oils that resemble structure of saturated fats and considered unhealthy omega 3 fatty acids - "heart healthy"

Question 56

phospholipids

Answer 56

modified triglycerides - glycerol and 2 fatty acids plus a phosphorus containing group - head and tail regions have diff properties - head is polar - hydrophilic (likes water) - tail is nonpolar - hydrophobic (hates water) important in cell membrane structure

Question 57

steroids

Answer 57

consist of 4 interlocking ring structures - starting material for synthesis of vit D, steriod hormones, and bile salts - important in cell plasma membrane structure - most important steroid is cholesterol which is made in the liver and found in animal products

Question 58

proteins

Answer 58

comprise of 20 to 30 % of call mass and has most functions of any molecule (structure, chemical - enzymes, contraction - muscles) contain C, H, O, N, and sometimes S + P - polymers of amino acid monomers held together by peptide bonds

Question 59

protein denaturation

Answer 59

globular proteins unfold and lose their functional 3D shape - can be caused by increased acidity or increased temp and usually reversible, however in changes are extreme it can be irreversible

Question 60

nucleic acids

Answer 60

composed of C, H, O, N, and P and are the largest molecule in the body - nucleic acid polymers are made up of monomers called nucleotides which are composed of a nitrogen base, a pentose sugar, and a phosphate group ex. DNA and RNA

Question 61

ATP

Answer 61

adenosine triphosphate - chemical energy released when glucose is broken down is captured in ATP - directly powers chem reactions in cells (offers immediate useable energy) structure - adenine-containing RNA nucleotide with two additional phosphate groups