Chemistry of Life and Macromolecules

Question 1

what is the simplest form of matter / cant be broken down to other substances?

Answer 1

element

Question 2

what chemical takes up 65% of our body? why is it needed?

Answer 2

oxygen - part of water, needed for cellular respiration

Question 3

what chemical takes up 18.5% of our body? why is it needed?

Answer 3

carbon - backbone of all organic molecules

Question 4

what chemical takes up 9.5% of our body? why is it needed?

Answer 4

hydrogen - found in nearly every compound in the body

Question 5

what chemical takes up 3.2% of our body? why is it needed?

Answer 5

nitrogen - part of proteins and nucleic acids

Question 6

what chemical takes up 1% of our body? why is it needed?

Answer 6

phosphorous - bones, teeth, nucleic acids, and atp (energy)

Question 7

what chemical takes up 0.3% of our body? why is it needed?

Answer 7

sulfur - part of some proteins

Question 8

what are trace elements?

Answer 8

present in the body in much smaller amounts (ex: calcium, iodine, iron)

Question 9

what is an atom?

Answer 9

the smallest components of elements

Question 10

how does a proton affect the nucleus?

Answer 10

they have a positive charge and determine the elemental identity

Question 11

how does a neutron affect the nucleus?

Answer 11

they have no charge and determine (w/ protons) the mass

Question 12

what are electrons?

Answer 12

they are negatively charged and orbit the nucleus. They determine what chemical bonds the atom will form

Question 13

what needs to happen for an atom to be considered neutral?

Answer 13

needs to have equal numbers of protons and electrons so the charges cancel out

Question 14

how does an atom become an ion?

Answer 14

atoms need to have gained or lost an electron

• positive: lost an electron
• negative: gained an electron

Question 15

what are ions found in the body cells or fluids called?

Answer 15

electrolytes

Question 16

what is the difference between a compound and a mixture?

Answer 16

a compound is a single molecule made of 2 or more elements.

a mixture contained compounds and elements in the same place although, they are not chemically combined

Question 17

what is the difference between an ionic bond and a covalent bond?

Answer 17

an ionic bond is an attraction between oppositely charged ions formed when electrons are transferred.

a covalent bond is formed by 2 or more atoms sharing electrons.

Question 18

what is a hydrogen bond?

Answer 18

when the negative end of one molecule attracts the positive end of another.

Question 19

what must a polar molecule have?

Answer 19

both positive and negative ends

Question 20

what are the 5 properties of water and their definitions?

Answer 20

1. polarity - has both
2. cohesion - the attraction of water molecules to each other (droplets)
3. adhesion - the attraction of water molecules to a surface
4. heat capacity - a large amount of heat energy is needed to raise temperature
5. universal solvent - can dissolve any ionic or polar covalent compound

Question 21

what is the difference between solutes and solutions?

Answer 21

solutes: the substance that dissolves water
solutions: the results of the dissolving

Question 22

what is an acid?

Answer 22

compounds that release hydrogen ions in water

Question 23

what is a base?

Answer 23

release hydroxide in water

Question 24

what is a neutral solution?

Answer 24

release equal amounts of both ions

Question 25

how do you measure a pH scale?

Answer 25

<7 means acids = 7 means neutral >7 means bases

Question 26

what is a buffer system?

Answer 26

mixtures of chemicals that can maintain a certain pH by either absorbing or releasing H+ ions

Question 27

what is the definition of organic chemistry?

Answer 27

the structures and properties of the essential molecules of living organisms.

Question 28

what is the importance of carbon?

Answer 28

the central element because it can form 4 bonds, more than most elements

Question 29

what is the difference between polymers and monomers?

Answer 29

polymer: repeating units monomer: individual units

Question 30

what are the 4 macromolecules in organic chemistry?

Answer 30

1. nucleic acids 2. carbohydrates 3. proteins 4. lipids

Question 31

what is the function of nucleic acids?

Answer 31

compounds used to store instructions within cells

Question 32

what is the structure of nucleotides?

Answer 32

molecules containing phosphate, 5 carbon sugar, and a nitrogenous base

Question 33

what is the purpose of DNA?

Answer 33

contains all an organisms genetic information in the nucleus of each cell

Question 34

what is the function of nitrogenous bases?

Answer 34

they form the 'rungs' of the molecule

Question 35

what is RNA?

Answer 35

similar to DNA, but found outside the nucleus

Question 36

what is the purpose of ATP?

Answer 36

used to transfer energy within cells

Question 37

what is ATP's relationship with ADP?

Answer 37

ATP is broken down in ADP when energy is needed

Question 38

what are carbohydrates made of?

Answer 38

carbon, hydrogen, oxygen

Question 39

how many units do monosaccharides have? (purpose?)

Answer 39

1 sugar monomer; short term energy storage

Question 40

how many units do disaccharides have? (purpose?)

Answer 40

2 sugar monomers; energy storage

Question 41

how many units do polysaccharides have? (purpose?)

Answer 41

3+ monosaccharides; energy storage and protection

Question 42

what are lipids made of?

Answer 42

molecules made mostly of carbon and hydrogen (not polymer)

Question 43

are lipids hydrophobic or hydrophilic?

Answer 43

hydrophobic, don't dissolve

Question 44

what is the difference between saturated fatty acids and unsaturated fatty acids?

Answer 44

saturated fatty acids are long chains of carbon atoms with single bonds only unsaturated fatty acids are long chains of carbon atoms with single & double bonds

Question 45

saturated fatty acids are ___ at room temperature

Answer 45

solids

Question 46

unsaturated fatty acids are ___ at room temperature

Answer 46

liquids

Question 47

what are triglycerides made of?

Answer 47

glycerol, 3 carbon molecules, 3 fatty acids

Question 48

what are triglycerides functions?

Answer 48

primary component of body fat as energy storage

Question 49

what does the structure of phospholipids include?

Answer 49

2 fatty acids and a phosphate head: hydrophilic + charged tail: hydrophobic + no charge

Question 50

what is the structure of steriods?

Answer 50

lipids with 4 interconnected carbon rings

Question 51

what are proteins?

Answer 51

polymers made of amino acids with a wide variety of functions and structures

Question 52

list the functions of proteins? (7)

Answer 52

1. support 2. movement 3. transport 4. buffering 5. metabolic regulation 6. coordination 7. defense

Question 53

the ____ of amino acids determines the ___ of a protein which then determines its ____

Answer 53

sequence, shape, function

Question 54

what are enzymes?

Answer 54

proteins that catalyze or speed up the rate of a chemical reaction in the body

Question 55

what is a substrate?

Answer 55

molecule the enzyme work on

Question 56

what do enzymes produce?

Answer 56

a product, molecules that result from the cataclyzed reaction

Question 57

describe the lock & key theory

Answer 57

each enzyme will only be active against the substrate that fits it shape