Exam 1

Question 1

Atoms

Answer 1

• have the same # of protons and electrons
• atomic # = # of protons
• mass # = #of protons plus # of neutrons

Question 2

homeostasis

Answer 2

the ability to maintain an internal “constancy”

Question 3

Metabolism

Answer 3

the sum total of all chem rxn ( anabolic and catabolic) that serve to generate and consume energy

Question 4

energy

Answer 4

the ability to perform work

Question 5

anabolic

Answer 5

build up (synthesis)

Question 6

catabolic

Answer 6

break down (digestive)

Question 7

What must occur for evolution to occur?

Answer 7

1. variation within the population with respect to alleles

2. something to ACT on this variation

Question 8

What are the minimum qualifications to build a cell?

Answer 8

1. membrane
2. DNA
3. cytoplasm with dissolved “goodies”

Question 9

what elements make up the human body?

Answer 9

Carbon, Hydrogen, Oxygen, Nitrogen

Question 10

isotope

Answer 10

2 isotopes of a chemical element have the same # of protons, but different # of neutrons

Question 11

radio isotope

Answer 11

an isotope that is unstable , emit (decay) subatomic particles to become stable

Question 12

Dangers of radioactivity:

Answer 12

• Destroys whole cells/ organs
• can denature proteins
• mutate DNA

Question 13

Good things about radioactivity:

Answer 13

• nuclear power
• medical uses (PET scan, thyroid scan)
• food preservation
• radio- labeling biomolecules

Question 14

Ionic Bonds-

Answer 14

• an electron is transferred from one atom to another

- strong (solid)

Question 15

covalent bonds:

Answer 15

• a pair(s) of electrons are shared among 2 atoms

Question 16

hydrogen bonds-

Answer 16

a weak interaction between a partially + Hand another partially - atom (usually O or N)

Question 17

what makes H2O such an important molecule for life?

Answer 17

1. H2O is a great temp. Stabilizer
2. H2O has a high heat of vaporization
3. ice floats
4. H2O is a “sticky” molecule —– cohesion: H2O to H2O attraction, adhesion: h2o to other polar molecule attraction
5. excellent solvent for polar substances

Question 18

maintaining human blood pH at 7.4

Answer 18

• excretory system (kidneys)

- buffers in our blood- bicarbonate system (baking soda)

Question 19

maltose

Answer 19

-glycosidic linkage

Question 20

what do we absorb

Answer 20

monomers

Question 21

functions of monosaccharides

Answer 21

1. immediate source (best) of energy

2. carbon backbone can be used to synthesis other monomers

Question 22

functions of polysaccharides

Answer 22

1. storage (long- term) source of energy

2. structural

Question 23

acidic proteins

Answer 23

• negatively charged
• aspartic acid (ASP or D)
• glutamic acid (GLU or E)

Question 24

Basic proteins

Answer 24

• positivity charged
• lysine (LYS or K)
• arginine (ARG or R)
• histidine (HIS or H)

Question 25

Cysteine

Answer 25

- pH= 7 - side chain: -CH2-SH - proteins always contain S

Question 26

pepide bond

Answer 26

between 2 A.A

Question 27

Primary Structure

Answer 27

linear

Question 28

Secondary structure

Answer 28

- regular, patterned folding due to H- bonding between backbone atom - Helix, b- sheet

Question 29

tertiary structure

Answer 29

irregular, non-patterned folding due to interactions between side-chains

Question 30

quaternary structure

Answer 30

interaction of more than 1 polypeptide chain to generate a multi- subunit protein

Question 31

fats

Answer 31

glycerol (3-carbon alcohol), 3 fatty acids

Question 32

Saturated fat

Answer 32

- max # of H bond to fatty acids. no double bond between C atoms in long-chain fatty acid. - Solid at RT

Question 33

unsaturated fat

Answer 33

more than or equal to 1 double bond between C atoms. Mostly made by plants -liquid at RT

Question 34

structure of a amino acid

Answer 34

``` H R O l l ll N--- C--- C l l l H H OH ```

Question 35

-non-polar:

Answer 35

= sharing of electron atom pair(s), 2 identical atoms

Question 36

- polar:

Answer 36

unequal sharing of electron pairs