Chapter 2 (Chemistry) Flashcards
Define atom
the smallest chemical unit of matter
Define molecule
two or more atoms held together by chemical bonds
Define compound
a molecule containing atoms of more than 1 element
Define element
matter that is composed of a single type of atom
Define dehydration synthesis
-reactions that make macromolecules
-dehydration=removing water synthesis= making
(H2O would be at the end need energy)
Define hydrolysis
-reactions that break macromolecules
-hydro (water) -lysis (to break or cut)/ release energy
Define inorganic
-molecule lacking carbon
Define organic compound
-molecules that contain both carbon & hydrogen atoms
Define hydrophobic
-“water fearing/hating)
-does not dissolve in water
Define hydrophilic
-“water loving”
-does dissolve in water
Describe the parts of an atom
Protons (in nucleus of atom), neutrons (in nucleus of atom has no charge ), electrons
What are the elements commonly found in living organisms?
CHONPS
Carbon
Hydrogen
Oxygen
Nitrogen
Phosphorus
Sulfur
Compare/Contrast ionic, covalent, hydrogen bonds
Which is the strongest? Weakest?
Ionic bond: bond holding Na+ and Cl- ions in NaCl
Covalent bond: bonds holding hydrogen & oxygen atoms in 1
molecule of H2O (shraing of pair of electrons
between two atoms)
Hydrogen bond: (—–)
Strongest–>Covalent bond
ionic bond
Weakest –>Hydrogen bond
Compare/contrast polar & nonpolar covalent bonds
-polar unequal sharing of electrons
Define electronegativity and explain how it affects a covalent bond
-The attraction of an atom for electrons
-double covalent bond
Know the unique properties of water
COHESION: H bonds hold molecule together
ICE IS LESS DENSE THAN WATER: ice float in lakes allow life to
continue below surface
HIGH SPECIFIC HEAT: absorbs large amount of energy b4
breaking H bonds–> will hold temp. well;
help moderate temp
HIGH HEAT OF VAPORAION: as water evaporates it takes
heat–> cooling effect
(sweating)
UNIVERSAL SOLVENT: polar & ionic substances dissolve in
water to form solutions
dehydration synthesis vs. hydrolysis
What do these types of chemical reactions have to do with macromolecules?
Dehydration synthesis: removing water (@ end need energy)
Hydrolysis: Water breaking ( release energy)
-Used to make and break macromolecules
Be able to identify the following functional groups: hydroxyl, amino, carboxyl, sulfhydryl, phosphate
Hydroxyl group: OH
Amino group: NH2
Carboxyl group: O-C-OH
Sulfhydryl group: S-H
Phosphate group: -P-
What is a macromolecule?
o For the four macromolecules we studied
Carbohydrates, Lipids, Proteins, Nucleic Acids
Carbohydrates:
What is the subunit?
What type of bond holds the subunits together?
Where do you find it?
What does it do?
What elements make it up?
SUBUNIT: monosaccharide (disaccharide 2 monosaccharides,
polysaccharide)
BOND: glycosidic
FIND IT? : glucose, cellulose
WHAT DOES IT DO? : structural elements & energy storage
WHAT ELEMENTS MAKE IT UP: C H2 O
Proteins:
What is the subunit?
What type of bond holds the subunits together?
Where do you find it?
What does it do?
What elements make it up?
SUBUNIT: amino acids
BOND: peptide bonds (2° hydrogen bond)
FIND IT? : keratin & collagen
WHAT DOES IT DO? : Transport/ receptors/ enzymes/
structural/antibodies
WHAT ELEMENTS MAKE IT UP: C,H,O,N,P,S
Lipids:
What is the subunit?
What type of bond holds the subunits together?
Where do you find it?
What does it do?
What elements make it up?
SUBUNIT: fatty acids 1) triglycerides: 3 fatty acids joined to a
glycerol molecule
Oil-unsaturated double bonds C-kink
Fat- saturated sold butter
2) Phospholipids: 2 fatty acid +1
phosphate linked to glycerol forming
backbone (amphipathic: phobic one
end and phillic other end)
BOND: ester bond
FIND IT? : fats, oils, cholesterol
WHAT DOES IT DO?: messenger molecules( steroids)
energy reserve,
cell membrane (phospholipids)
WHAT ELEMENTS MAKE IT UP: C H O P
STERIODS: 4 rings structure
uses- hormones, light harvesting, maintain membrane fluidity
@ low temp.
Nucleic acids:
What is the subunit?
What type of bond holds the subunits together?
Where do you find it?
What does it do?
What elements make it up?
SUBUNIT: nucleotides
BOND: phosphodiester bond
FIND IT? : DNA & RNA
WHAT DOES IT DO? :genetic material, energy (ATP),
electron carriers(NAD, FAD)
WHAT ELEMENTS MAKE IT UP: C H O N P
Why do phospholipids form membranes?
2 fatty acids monomers + 1 phosphate linked to a glycerol forming a backbone. They are amphipathic (hydrophobic-tail @ one end and hydrophilic @ other end) Micelle, bi-layer sheet, liposome (center hydrophilic-head)
Describe the 4 levels of protein structure
1°: determine all higher levels of structure
-sequence of amino acids join by dehydration synthesis &
from peptide bonds
2°: hydrogen bond between members of peptide “backbone”
(carboxyl & amino group)
- R groups not involved
- alpha helix & beta sheet
3°: Hide hydrophobic amino acids from water
- 1 subunit
-shape is stabilized by bonds between R groups
-hydrogen bond(–), ionic (+/-),covalent (-), disulfide (s-s)
4°: functional structure
- 2 subunits
-shape is stabilized by bonds between R groups
-hydrogen bond(–), ionic (+/-),covalent (-), disulfide (s-s)
Compare/contrast DNA and RNA
Recognize the structure of the nucleotide
Be able to tell me which end is 5’ and 3’
General functions of nucleotides/nucleic acids
-Monomer=nucleotides (DNA & RNA)
a. nitrogenous base
b. pentose sugar
c. phosphate
-two types of pentose sugar
1. Ribonucleotide in RNA (pentose has
hydroxyl group @ carbon 2 is Ribose)
2. Deoxyribonucleotide in DNA (just H+
no hydroxyl have deoxyribose b/c
removed)
DNA: deoxyribose + phosphate+ a base(adenine, guanine, cytosine, thymine-specific for DNA-)
-polymer is often double stranded &
twisted alpha helix
RNA: ribose+ phosphate+ a base (adenine, guanine, cytosine, uracil-specific for RNA-)
-polymer is most often a single strand
-3’ end OH
-5’ end P
Define ion
an atom that has a full positive or negative charge
