lec 2 building blocks of life

Question 1

what is an atom?

Answer 1

smallest unit of an element that has some chemical characteristics of that element

Question 2

what are atoms made of? what are their charges? (3 particles)

Answer 2

protons-positive charge
electrons- negative charge
neutrons- no charge (neutral)

Question 3

what orbit the nucleus? What does it mean if electron shells are completely full?

Answer 3

electron shells

the atom is stable

Question 4

what does an atoms chemical identity (# on periodic table) depend on?

Answer 4

number of protons in the atom

Question 5

what is a bond? what do bonds form?

Answer 5

chemical linkages that hold atoms together to form molecules

Question 6

why and how do elements form bonds?

Answer 6

form bonds to become stable, they form by taking or sharing electrons from other atoms

Question 7

what is a covalent bond?

Answer 7

forms when atoms share electrons

Question 8

what are non-covalent bonds? where do they form? strength of bonds in relation to covalent?

Answer 8

when an atom gains/loses electrons to become more stable (NO SHARING)

form between and within molecules

weaker than covalent bonds

Question 9

what are 2 main types of non-covalent bonds?

Answer 9

hydrogen, ionic

Question 10

what type of bonds are hydrogen bonds? what kind of molecules do they form between?

Answer 10

non covalent bonds, form between polar molecules

Question 11

what are polar molecules?

Answer 11

molecules with uneven pole distrubution (poles are charge of either side if molecule)

Question 12

what are ions?

Answer 12

atoms that have lost or gained electrons

Question 13

if an atom gains an electron, what charge does it have?

Answer 13

negative

Question 14

what are ionic bonds?

Answer 14

bonds that form between atoms of opposite charge

Question 15

what is an example of an ionic bond?

Answer 15

Salt in water (NaCl + H2O)

Question 16

what are the 4 major classes of chemical compounds in living organisims?

Answer 16

1. sugars
2. nucleotides
3. amino acids
4. fatty acids

Question 17

why is carbon important? what shapes can it form in?

Answer 17

predominant element in compounds
versatile
can form chains, branches or rings

Question 18

what is monomer

what element do they contain

Answer 18

small carbon containing molecules, can exist as individual molecules
individual small molecule with 20 or less atoms

Question 19

what is a polymer

Answer 19

macromolecules
made of joined monomers

Question 20

give 3 examples of monomers

Answer 20

sugars, amino acids, nucleotides

Question 21

give 3 examples of polymers

Answer 21

DNA, protein, polysaccharides

Question 22

sugars and their polymers are called

Answer 22

carbohydrates

Question 23

what is a monosaccharide? example?

Answer 23

-simplest type of sugar (monomer)
-basic unit of carbohydrates
ex. glucose

Question 24

what is a monosaccharide made up of in what ratio ?

Answer 24

carbon, hydrogen, oxygen
1:2:1

Question 25

what is a disaccharide? what kind of reaction ?

Answer 25

2 monosaccharides joined by a covalent bond dehydration

Question 26

reactions in which water is added/removed? what does it do with respect to monomers?

Answer 26

dehydration- links monomers, water removed hydrolysis- breaks monomers apart, water added

Question 27

what is a polysaccharide and give 3 examples

Answer 27

thousands of joined monosaccharides glycogen, cellulose, starch

Question 28

how are polysaccharides formed?

Answer 28

dehydration rxn b/w monomers

Question 29

What is a nucleotide ?

Answer 29

5 carbon sugar molecule base molecule a phosphate

Question 30

what makes up DNA RNA

Answer 30

nucleotides (monomers)

Question 31

DNA and RNA are.. | type of molecule

Answer 31

polymers

Question 32

thymine, cytosine _______ & ________ are in __________

Answer 32

guanine or adenine DNA

Question 33

RNA contains uracil, _________

Answer 33

guanine or adenine , cytosine

Question 34

explain phosphate component. How many phosphate groups can a nucleotide have?

Answer 34

-phosphorous+oxygen -nucleotide can have 1,2,3 phosphate groups bound to the sugar

Question 35

what are the monomers that form protein polymers?

Answer 35

amino acids

Question 36

what is the basic structure of amino acid

Answer 36

-alpha carbon -carboxyl group -amino group -side chain

Question 37

what is a peptide bond

Answer 37

amino acids are covalently linked

Question 38

what is a peptide? polypeptide? what do polypeptides form?

Answer 38

peptide: 2+ amino acids joined by peptide bonds polypeptide: chain of many amino acids protein: 1+ polypeptides long chains of amino acids held together by peptide bonds

Question 39

what are the 4 protein structures? what does each one look like?

Answer 39

primary- amino acids linked tgt, looks like beads on necklace secondary- either helix (spiral) or beta-pleated sheets (accordion folded strip) tertiary- protein folds into 3d structure quaternary- more than 1 polypeptide chain, each in own tertiary structures

Question 40

What is the cause of each shape? excluding primary

Answer 40

secondary- hydrogen bonding of peptide backbone, AA fold in repeating pattern tertiary- side chain interactions causes folding quaternary- more than 1 polypeptide chain

Question 41

what are lipids? polymers or not?

Answer 41

organic compounds made of fatty acids, insoluble in water NOT polymers

Question 42

What makes a lipid unsaturated? Where are they found?

Answer 42

1 or more double bonds in lipid plants

Question 43

what makes a lipid saturated? where are they found?

Answer 43

only single bonds in lipid animals

Question 44

What are carbohydrates made of, in what ratio?

Answer 44

carbon, hydrogen, oxygen 1:2:1 ratio

Question 45

What does hydrophobic mean? Hydrophilic?

Answer 45

hydrophobic- water fearing hydrophilic- water loving

Question 46

What is a fatty acid? What is its structure?

Answer 46

organic molecule -hydrophobic hydrocarbon chain + hydrophilic head group

Question 47

what are fatty acids found in?

Answer 47

-phospholipids -glycerides -waxes