Unit 1 Flashcards
What’s a macromolecule
- big
- made of few, common atoms
- accomplish all life functions
- put together in a special way
- can be incredibly complex
What are the 4 main kinds of macromolecules
- carbohydrates
- lipids
- proteins
- nucleic acids
macromolecules exist in two forms for all kinds of macromolecules except ______.
lipids
monomer definition
the simplest unit
polymer definition
a large molecule made of repeating monomers
How do macromolecules switch from monomers to polymers and vice versa
hydrolysis and dehydration synthesis (adding and removing water)
Describe dehydration synthesis
- forms polymers from monomers
- produces a water molecule
- builds complexity (anabolic)
- requires energy (endergonic) and enzymes
describe hydrolysis
- forms monomers from polymers
- uses water to break peptide bond
- reduces complexity (catabolic)
- releases energy (exergonic) and enzymes
Carbohydrates
1. examples
2. elements
3. function
4. monomer
5. extra fact
- sugar & starches
- made of C, H, and O (1:2:1 ratio in monomers)
- used for short term energy storage and structure
- monomers = monosaccharides
- different sugar monomers can have different #s of carbon
monosaccharides
- most famous = hexose sugars
- hexose sugars = glucose, galactose, and fructose
- carbon rings typically
disaccharides
- formed when two monosaccharides go through dehydration synthesis
- Glucose + Glucose = maltose
- Glucose + Fructose = sucrose
- Glucose + galactose = lactose
polysaccharides
massive polymers of sugar
functions of glucose polymers in organisms
energy storage: short term (plants use amylose and animals use glycogen)
structural support: (plants use cellulose and animals use starch) (starch = alpha linked) (cellulose = beta linked)
digesting cellulose
herbivores need to digest cellulose. most animals lack enzymes needed to break beta linkages
termites: use protists, which they have a symbiotic relationship with
ruminants (cows): bacteria and continual regurgitation
Caecophores (bunnies): expanded lower GI tract (instead of regurgitation, they eat their poop)
chitin definition
a modified polysaccharide; used in fungi cell walls, arthropod exoskeletons; and dissolving stitches
peptidoglycan definition
a modified polysaccharide; used in bacterial cell walls
lipids
- fats, oils, waxes
- made of C, H, and O
- long-term energy and insulation
- no polymers
- 3 major groups: triglycerides, phospholipids, and steroids
triglycerides
- made of one glycerol and three fatty acids
- connected by dehydration synthesis
saturated fats
no double bonds between carbons; straight; solid at room temp; bad for you
unsaturated fats
at least one double bond; bends at each double bond; liquid at room temp; good for you
phospholipids
- modified triglycerides
- makes the molecule have a polar and non-polar region (amphipathic)
- the major component of cell membranes (phospholipid bilayer)
steroids
- one class of hormones and cholesterol
- notable structure = fused rings
- presence of different functional groups = different functions
proteins
- most complex biological molecules
- C, H, O, N, and some S
- used to accomplish all life functions
- all are polymers of amino acid monomers
- amino acids are joined by peptide bonds (dehydration synthesis)
amino acids
- 21 known
- all contain an amino & carboxyl & R group bonded to a central alpha carbon
- all contain an R group (variable group) that make the structures of each amino acid differ
- R-group structure varies widely
- NH is positive; O is negative
primary structure
what is it: the sequence of amino acids in one polypeptide chain
how it happens: peptide bonds between amino acids
secondary structure
what is it: regular, repeating 3D structures found in all polypeptide chains (alpha helix or beta pleated sheet)
How it happens: hydrogen bonding between atoms in the CN backbone of the polypeptide (no R-groups involved)
tertiary structure
What is it: the specific 3D shape of a particular polypeptide chain (the conformation)
How it happens: interactions between R-groups and the local environments of the cell
quartenary structure
What is it: the specific 3D shape of any protein that is made of more than one polypeptide chain (many are); the only optional structure level
How it happens: the overall structure when multiple chains form a functional protein
protein functions
storage proteins; hormonal proteins; structural proteins; defensive proteins; transport proteins; receptor proteins; contractile and motor proteins; enzymatic proteins
hemoglobin
it carries oxygen in your red blood cells; in sickle cell anemia, hydrophobic portion replaces the original hydrophilic portion, changing the shape and how well it functions
denaturation definition
denaturation: change in the structure of a protein. denatured proteins do not work well if at all. There is a direct relationship between a protein’s conformation and its function. They can usually go back to their original form
proteomics
the study of protein structure and function
nucleic acids
- the information storage molecule for biological systems
- made of C, H, O, N & P
- DNA & RNA
- all are polymers of nucleotides
- nucleotides = a phosphate, a pentose sugar, and a nitrogenous base (adenine, thymine, guanine, cytosine, and uracil)
DNA vs RNA
DNA: deoxyribose pentose sugar; no uracil; 2 strands
RNA: ribose pentose sugar; no thymine; 1 strand
DNA (deoxyribonucleic acid) functions
- stores information about the primary structure of proteins, and the sequences of RNA molecules
- is heritable
DNA structure
phosphodiester bonds: 2 chains of covalently bonded nucleotides, from sugar to phosphate
chains bonded to each other by hydrogen bonds between N bases
A-T and G-C
purine (A, G) oposite to pyrimidine (T, C)
DNA discovery
2nd most important discovery
watson and crick published the paper
wilkins and franklin did the X-ray diffraction work
RNA (ribonucleic acid) functions
- transmits and translates DNA information into protein
- many enzymatic and regulatory functions
- There is 1 kind of DNA but 15 types of known RNA
RNA structure
less stable than DNA
1 strand but base pairing still occurs (A-U)
Central dogma definition
the process used to describe how the information stored in DNA moves to RNA before some of that info finally directs the construction of proteins
atoms definition
the smallest fundamental unit of matter
atom = elements
120 elements: 4 major (CHON), 10 minor, 30-50 trace elements
energy and atoms
- energy holds electrons to the nucleus
- when atoms absorb energy, electrons are moved to higher energy levels
- the movement of electrons back to lower energy levels releases energy as EM radiation
atoms bond
bonding is accomplished by electrons interacting between atoms; ionic bonds (not many possible combinations) and covalent bonds (infinite combinations, all important biological molecules are covalently bonded)
polarity definition
the unequal sharing of electrons in a covalent bond; leads to unequal distribution of charge in the molecule; polar molecules are attracted to other polar molecules; hydrogen bonds are the strongest attractions between the most polar molecules
bonds determine _____ & ______
shape; function
chemical reactions
all result in the breaking and forming of bonds; in any reaction, mass, energy, and charge are conserved
compounds
the properties of a compound can be very different from the properties of the elements that make them
emergence definition
increasing levels of complexity in a system can demonstrate novel properties not seen in the levels below them
radioactivity
- atoms with unstable nuclei are radioactive
- spontaneous emission of high energy particles until stability is reached
- excess radiation is damaging to biological systems
- radiation is used in biology as molecular tags
water
the majority of any organism is water; it is needed for life; it is one of the few substances that exists in all three phases at normal terrestrial conditions
water properties (8)
cohesion: sticking together
adhesion: sticking to other things
high surface tension: due to cohesiveness
transpiration: the movement of water through tree caused by adhesion and cohesion
high specific heat: how much heat is absorbed/released before an increase/decrease in temperature
ice is less dense than liquid water
the closest thing to the universal solvent
it dissociates into H and OH
pH definition
a measure of acidity; the -log of the H3O+
carbon properties (4)
carbon is tetravalent (it makes 4 bonds to get stable)
it’s abundant
it’s versatile
building blocks of life
vitalism definition
belief in a life force
mechanism definition
theory that there is nothing special about how life is built
isomers definition
molecules with the same molecular formula but different structures
structural = same formula, different order
cis-trans = same formula, different positioning around a double bond
enantiomers = same formula, mirror image positioning around a central carbon (D-sugars & L-amino acids)
functional groups (7)
- hydroxyl: —OH or HO—
polar; forms hydrogen bonds with water to help dissolve organic compounds - carbonyl: —C then branches - double bond to O on top, nothing on single bond going downward
structural isomers; ketones if within carbon skeleton; aldehydes if at end of carbon skeleton - carboxyl: —C then branches - double bond to O on top, single bond to OH on bottom
can donate H; can be nonionized or ionized - amino: —–N then branches - single bond to H on top, single bond to H on bottom
can pick up an H; can be nonionized or ionized - sulfhydryl: —-SH or HS—
two can react to form a covalent bond that stabilizes the protein structure; can determine curliness or straightness of hair with cysteine proteins - methyl: —C—-H; branches at C, single bond with H on top and bottom
affects the expression of genes - phosphate: —O—P—O–; branches at P, double bond with O on top and single bond with O on bottom
contributes negative charge; can react with water to release energy
