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261 Cards in this Set
- Front
- Back
living things are composed of 4 major classes of macromolecules: |
carbohydrates, lipids, proteins, & nucleic acids |
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A polymer is a _______ molecule composed of... |
large many repeated subunits |
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most macromolecules are made from... |
single subunits, or building blocks, called monomers |
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type of reaction used to form polymers out of monomers |
dehydration synthesis or condensation reaction (release water molecules as a byproduct) |
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loss of water = _________ release of water = _________ |
= dehydration = condensation |
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polymers are broken down into monomers in a process known as |
hydrolysis - hydro = water - lysis = break |
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Dehydration and hydrolytic reactions are _______, or "________" by .... |
catalyzed, or "sped up" ... enzymes specific for that particular chemical reaction |
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enzymes are typically |
proteins (RNA can also have enzymatic properties) |
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specific stoichiometry of carbohydrates |
(CH2O)n where n is the # of carbons |
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ratio of C:H:O in carbohydrates |
1:2:1 |
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carbohydrates are typically classified into the following subtypes: |
monosaccharides, disaccharides, polysaccharides |
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mono |
one |
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sacchar |
sweet |
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Simple sugars |
monosaccharides |
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most monosaccharides end in |
-ose |
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depending on the number of carbons, monosaccharides may also be known as... |
trioses (3 carbons) pentoses (5 carbons) hexoses (6 carbons) |
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chemical formula for glucose |
C6H12O6 |
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glucose is important as |
A source of energy |
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glucose is made |
by plants using carbon dioxide and water |
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excess glucose in plants is stored as |
starch |
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Name 3 common monosaccharides |
glucose galactose (part of lactose) fructose (found in sucrose, in fruit) *isometric monosaccharides (hexoses) *glucose and galactose are aldoses *fructose is a ketose |
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glucose is a(n) ___ose |
- aldose - hexose |
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galactose is a(n) ___ose |
- aldose - hexose |
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fructose is a(n) ___ose |
- ketose - hexose |
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monosaccharides can exist as |
A linear chain OR ring-shaped molecules |
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T/F monosaccharides are ring shaped only |
F |
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T/F monosaccharides can exist as a linear chain or as ring shaped molecules |
T |
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T/F monosaccharides can exist as a linear chain |
T |
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in aqueous solution, monosaccharides are usually |
found in ring forms |
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glucose in a ring form can have ____ different arrangements.... |
2 of the OH group around the 1st carbon - above = α - below = β |
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disaccharides form when |
two monosaccharides undergo a dehydration reaction |
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the _______ bond formed between carbohydrate molecules is known as... |
covalent glycosidic bond, - aka glycosidic linkage |
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glycosidic bonds can be.. |
of the α- or β- type |
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Name 3 common disaccharides |
lactose maltose sucrose |
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lactose |
- disaccharide - glucose + galactose |
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maltose |
- disaccharide - glucose + glucose |
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sucrose |
- disaccharide - glucose + fructose |
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most common disaccharide |
sucrose |
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long chain of monosaccharides linked by _______ bonds |
polysaccharide glycosidic |
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A polysaccharide chain may... |
- be branched or unbranched - contain different types of monosaccharides |
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starch is a _____saccharide |
polysaccharide |
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stored form of sugar in plants |
starch |
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Name 2 starches |
amylose & amylopectin - both polymers of glucose |
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storage form of sugar in animals |
glycogen |
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glycogen is a ____________ molecule, usually stored... |
highly branched in liver and muscle cells |
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What happens when blood glucose levels decrease? |
glycogen is broken down to release glucose in a process called glycogenolysis |
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glycogenolysis |
break down of glycogen to release glucose into bloodstream |
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most abundant natural biopolymer |
cellulose |
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cell wall of plants is mostly made of |
cellulose |
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____ provides structural support to plant cells |
cellulose |
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wood and paper are mostly |
cellulose |
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cellulose is made up of |
glucose monomers linked by β 1-4 glycosidic bonds |
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What gives cellulose its rigidity and high tensile strength |
- glucose monomers linked by β 1-4 glycosidic bonds - every other glucose monomer is flipped over - monomers packed tightly as extended long chains |
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how do herbivores, such as ____, _____, ______, _____, and ______ digest cellulose? |
cows, koalas, buffalo, horses, & termites
specialized digestive flora (bacteria and protozoa) |
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are lipids polar or nonpolar? why? |
nonpolar they are hydrocarbons consisting of mostly nonpolar carbon-carbon or carbon-hydrogen bonds |
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cells store energy for long-term use as |
fat |
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Name some functions of lipids |
- Fats = long term energy storage - insulation from environment - building blocks of hormones - cell membranes |
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list 5 common lipids (broad categories) |
- Fats - oils - waxes - phospholipids - steroids |
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components of a fat molecule |
glycerol & fatty acids |
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glycerol is a(n) _______ with ... |
- organic compound (alcohol) - C3H5(OH)3 |
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fatty acids have a... |
long chain of hydrocarbons to which a carboxyl group is attached |
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number of carbons in a fatty acid may range from ___-___; most common are those containing .... |
4 to 36 12 to 18 |
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in a fat molecule ______ are attached to ________ with _______ |
fatty acids [are attached to] each of the 3 carbons of the glycerol molecule [with] an ester bond through an oxygen atom |
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during _____ bond formation in fat molecules ... |
ester 3 water molecules are released |
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the three fatty acids in __________ may be.... |
triaclyglycerol aka triglyceride similar or dissimilar |
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palmitic acid |
- saturated fatty acid - derived from the palm tree - common in meat |
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saturated fatty acid |
- fatty acid with only single bonds between neighboring carbons - saturated with hydrogen > ie the # of H atoms attached to the carbon skeleton is maxed |
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Name 3 examples of saturated fatty acids |
butyric acid, palmitic acid and stearic acid |
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stearic acid |
- saturated fatty acid - common in meat |
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most unsaturated fats are _________ and are called _____ |
liquid at room temperature oils |
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one double bond in fatty acid chain |
monounsaturated fatty acid e.g. olive oil |
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multiple double bonds in a fatty acid |
polyunsaturated fatty acid e.g. canola oil |
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butyric acid |
- saturated fatty acid - found in butter |
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mammals store fat in |
adipocytes |
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plants store fats in |
seeds > used as energy source during seedling development |
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unsaturated fats are usually of ______ origin and contain ..... |
plant cis unsaturated fatty acids |
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why are unsaturated fats liquid at room temperature? |
cis double bond causes a bend or "kink" that prevents the fatty acids from packing tightly |
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Recent studies have shown that an increase in trans fats in the human diet may lead to... |
an increase in low-density lipoproteins (LDL), or "bad" cholesterol, which may lead to plaque deposition in arteries, resulting in heart disease |
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essential fatty acids |
fatty acids required but not synthesized by the human body |
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name 2 essential fatty acids that must be supplemented through ingestion |
omega-3 omega-6 |
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why is it called an omega-3 fatty acid |
3rd carbon from the end of the hydrocarbon chain is connected to it's neighboring carbon by a double bond |
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major constituents of the plasma membrane |
phospholipids |
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phospholipids are composed of |
-fatty acid chains attached to a glycerol or sphingosine backbone -glycerol attached to 2 fatty acids (diacylglycerol) and a modified phosphate group |
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phospholipids are ________ molecules (water) |
amphipathic, containing a hydrophilic (phosphate-containing group)(head) and a hydrophobic (fatty acid chains)(tail) part |
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if a drop of phospholipids is placed in water.. |
it spontaneously forms a micelle, with phosphate heads facing the outside and fatty acids facing the interior |
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steroid structure |
-fused ring structure - 4 linked carbon rings - often with -OH (sterols) |
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why are steroids grouped with lipids |
steroids are hydrophobic |
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are steroids shaped like other lipids |
no |
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Cholesterol |
- common steroid - mainly synthesized in the liver - precursor to many steroid hormones e.g. testosterone & estradiol - precursor to vitamin D - precursor to bile salts - component of plasma membrane > found in phospholipid bilayer |
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bile salts |
help in the emulsification of fats and their subsequent absorption by cells cholesterol is a precursor |
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______ have the most diverse range of functions of all macromolecules |
proteins |
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Classifications f proteins |
1) structural 2) regulatory 3) contractile 4) protective 5) transport 6) storage 7) membranes 8) toxins 9) enzymes |
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all proteins are _____mers of _________, arranged .... |
polymers of amino acids in a linear sequence |
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3 examples of enzymes |
amylase trypsin kinases |
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enzyme function |
generally speed up specific chemical reactions |
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2 examples of transport proteins |
hemoglobin albumin |
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function of transport proteins |
carry substances throughout the body |
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2 examples of membrane transport proteins |
ion channels carriers |
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function of membrane transport proteins |
carry substances across the plasma membrane |
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2 examples of structural proteins |
actin tubulin |
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function of structural proteins |
cytoskeleton |
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1 example of defense proteins |
immunoglobulins |
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function of defense proteins |
protections |
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2 examples of motor proteins |
actin myosin |
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function of motor proteins |
movement |
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1 example of a storage protein |
albumin |
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function of storage proteins |
nourishment |
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enzymes are usually _______ or _______ proteins |
complex or conjugated |
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an enzyme is _____ for the _____ it acts on. |
specific substrate (reactant that binds to an enzyme) |
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enzymes that break down their substrates |
catabolic enzymes |
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enzymes that build more complex molecules from their substrates |
anabolic enzymes |
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hormones are usually |
small proteins or steroids |
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hormones are secreted by |
endocrine cells |
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hormones act to |
control or regulate specific physiological processes including: - growth - development - metabolism - reproduction |
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give an example of a hormone |
insulin - protein hormone - regulates blood glucose |
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some proteins are ______ in shape while others are ______ |
globular (hemoglobin) fibrous (collagen) |
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______ is critical to protein function |
shape |
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what may lead to permanent changes in the shape of protein? what is this called? |
changes in temp, pH, & exposure to chemicals denaturation |
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Proteins are made up of different arrangement of the same ____ types of _________ |
20 amino acids |
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______mers that make up proteins |
monomers amino acids |
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fundamental amino acid structure |
central (alpha (α)) carbon, bonded to an amino group (NH2), a carboxyl group (COOH), to a hydrogen atom, and to an R or side group |
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why the name "amino acid" |
amino group & carboxylic acid group |
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what differs among amino acids |
the R group |
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what determines the nature of an amino acid? |
the R group - determines charge (acid or basic), polar, or nonpolar |
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name three polar amino acids |
serine theonine cysteine |
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the side chains of what amino acid(s) are positively charged? these are also known as... |
lysine arginine basic amino acids |
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_____ has an R-group linked to the amino group, forming what structure |
proline ring like |
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the .... of amino acids ultimately determine the protein' s... |
sequence & number shape, size, and function |
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amino acids are linked via ____ formed by... |
peptide bonds dehydration reactions |
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what forms a peptide bond |
the carboxyl group of one amino acid and the amino group of another combine, releasing water |
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each polypeptide has a _______ at one end, called the _______, while the other end has a _______, called the _____. |
free amino group - N/amino terminal free carboxyl group - C/carboxyl terminal |
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a polypeptide is technically .... whereas .... |
a relatively short polymer of amino acids where's the term protein is used for longer polypeptides |
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the unique sequence of amino acids in a polypeptide chain is its |
primary structure |
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describe the structure of insulin |
-2 polypeptide chains, A & B, linked by to suicide bonds > the N terminal on the A chain is glycine > the C terminal on the A chain is asparagine *the sequences of the amino acids in the A & B chains are unique to insulin |
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the unique sequence for every protein is ultimately determined by |
the gene encoding the protein |
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what gives rise to the secondary structure of the protein |
local folding of the polypeptide |
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2 most common secondary protein structures |
α-helix and β-pleated sheet |
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explain an α-helix |
hydrogen bonds between the O in the carbonyl group of one amino acid and another amino acid 4 amino acids further along the chain |
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explain β-pleated sheet |
the "pleats" are formed by hydrogen bonding between atoms on the backbone of the polypeptide chain |
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the unique 3D structure of a polypeptide |
tertiary structure |
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what primarily creates and stabilizes the complex 3D tertiary structure of a protein? including what? |
interactions among R groups e.g. - ionic bonds, hydrophobic interactions, hydrogen bonding, and disulfide bridges/linkages |
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a proteins quaternary structure is formed by |
the interaction of a proteins subunits (polypeptides) |
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hemoglobin is formed by ____ subunits |
2 pairs (4 total) |
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how do proteins fold |
protein helpers, called chaperones (or chaperonins) associate with the target protein, prevent aggregation of polypeptides, and dissociate once it's folded |
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2 main types of nucleic acids |
deoxyribonucleic acid (DNA) ribonucleic acid (RNA) |
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genetic material found in all living organisms |
DNA |
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Where in the cell is DNA found |
nucleus (eukaryotes), organelles, chloroplasts, & mitochondria |
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information flow in an organism _______->________->________ |
DNA -> RNA -> protein |
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DNA dictates the structure of _____ during _______ |
mRNA during transcription |
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RNA dictates the structure of _______ during ______ |
protein during translation |
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what holds true for all organisms |
the central dogma of molecular biology |
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DNA & RNA are made up of |
monomers - nucleotides |
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nucleotides are composed of |
a nitrogenous base, a pentose sugar, and one or more phosphate groups |
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nucleotide bases in DNA |
adenine (A), guanine (G), cytosine (C), and thymine (T) |
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which are purines |
adenine and guanine |
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primary structure of a purine ? |
two carbon-nitrogen rings |
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which are pyramidines |
cytosine, thyamine, uracil |
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primary structure of pyramidines |
single carbon-nitrogen ring |
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RNA contains what bases |
A U G C |
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what are the sugars in DNA and RNA |
pentose sugars deoxyribose and ribose |
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what is the difference between ribose and deoxyribose? |
-OH group on 2nd carbon (ribose) -H on 2nd carbon (deoxyribose) |
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describe the structure of the _________ backbone of a DNA molecule |
phosphate-deoxyribose backbone The phosphate residue is attached to the OH group of the 5' carbon of one sugar and the 3' carbon of the sugar of the next nucleotide, which forms a 5'-3' phosphodiester linkage |
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how are polynucleotides formed? what is that linkage or bond called? |
requires the removal of 2 phosphate groups; forms phosphodiester bonds |
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T/F a phosphodiester linkage is formed through dehydration reactions |
F |
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T/F dehydration reactions are always used to link monomers in all macromolecules |
F phosphodiester linkages in polynucleotides |
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DNA has a double helix structure. Which components lie on the inside of the helix? The outside? |
inside: nitrogenous bases outside: sugar and phosphate -> backbone |
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what binds base pairs to each other in DNA |
h bonds |
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every base pair is separated from the next base pair by |
0.34nm |
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the two strands of DNA... |
run in opposite directions |
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the _______ orientation of DNA is important to.... |
antiparallel DNA replication & many nucleic acid interactions |
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What are the base pairs? |
A-T (U) G-C |
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DNA strands are _________ to each other |
complementary |
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If the sequence of one strand of DNA is AATTGGCC, what is the sequence of the complementary strand? |
TTAACCGG |
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During DNA replication... |
each strand is copied, resulting in a daughter DNA double helix containing one parental DNA strand and a newly synthesized strand |
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RNA is mainly involved in what process |
protein synthesis |
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RNA is usually |
single stranded & made if ribonucleotides linked by phosphodiester binds |
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4 major types of RNA |
messenger (mRNA) ribosomal (rRNA) transfer (tRNA) micro (miRNA) |
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What happens when a cell requires a certain protein to be synthesized? |
- the gene for the product is turned "on" - mRNA is synthesized - mRNA is read - protein product is made |
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If the DNA sequence is AATTGGCC, what is the sequence of the complementary RNA strand? |
UUAACCGG |
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mRNA interacts with what |
ribosomes and other cellular machinery in the cytoplasm |
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how is mRNA read? |
- in sets of 3 bases (codons) |
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What is a codon? |
-a set of three bases on an mRNA -codes for a single amino acid |
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rRNA - fast facts |
- major constituent of ribosomes - mRNA binds to it - ensures proper alignment of ribosomes & mRNA - enzymatic activity >catalyzes peptide bonds between 2 aligned amino acids |
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what type of RNA has enzymatic properties? what for? |
-rRNA - peptidyl transferase - formation of peptide bonds (AAs) |
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tRNA - fast facts |
- one of the smallest RNAs - usually 70-90 nucleotides long - carries AA to site of protein synthesis - base pairing between tRNA & mRNA allows for insertion of the correct AA in a polypeptide chain |
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miRNA - fast facts |
- smallest RNA - regulate gene expression by interfering with or degrading mRNA |
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alpha-helixstructure |
type of secondary structure of proteins formed by folding of the polypeptide into a helix shape with hydrogen bonds stabilizing structure |
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amino acid |
monomer of a protein has a central (alpha) carbon to which an amino group, a carboxyl group, a hydrogen, and an R group or side chain is attached the R group is different for all 20 amino acids |
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beta-pleated sheet |
secondary structure found in proteins in which "pleats" are formed by hydrogen bonding between atoms on the backbone of the polypeptide chain |
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biological macromolecule |
large molecule necessary for life that is built from smaller organic molecule |
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carbohydrate |
biological macromolecules in which the ratio of carbon to hydrogen and to oxygen is 1:2:1
serve as energy sources and structural support in cells & form the a cellular exoskeleton of arthropods |
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cellulose |
polysaccharide that makes up the cell wall of plants
provides structural support to the cell |
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chaperone |
aka, chaperonin protein that helps nascent protein in the folding process |
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chitin |
type of carbohydrate that forms the outer skeleton of all arthropods (e.g. crustaceans & insects) as well as the cell walls of fungi |
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dehydration synthesis |
aka condensation reaction links monomer molecules together, releasing a molecule of water for each bond formed |
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denaturation |
loss of shape in a protein as a result of changes in temperature, pH, or exposure to chemicals |
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deoxyribonucleic acid (DNA) |
double-helical molecule that carries the hereditary information of the cell |
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disaccharide |
2 sugar monomers that are linked together by a glycosidic bond |
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enzyme |
catalyst in a biochemical reaction that is usually a complex or conjugated protein |
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glycogen |
storage carbohydrate in animals |
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glycogen |
storage carbohydrate in animals |
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glycosidic bond |
bond formed by a dehydration reaction between two monosaccharides with the elimination of a water molecule |
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hormone |
chemical signaling molecule, usually a small molecule, protein, or steroid, secreted by endocrine cells that control/regulate specific physiological processes |
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hydrolysis |
reaction causes breakdown of larger molecules into smaller molecules with the utilization of water |
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lipid |
macromolecule that is nonpolar and insoluble in water |
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messenger RNA (mRNA) |
RNA that carries information from DNA to ribosomes during protein synthesis |
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monomer |
smallest unit of larger molecules called polymers |
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monosaccharide |
single unit or monomer of carbohydrates |
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nucleic acid |
biological macromolecule that carries the genetic blueprint of a cell & carries instructions for the functioning of the cell |
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nucleotide |
monomer of nucleic acids contains a pentose sugar, one or more phosphate groups, and a nitrogenous base |
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omega fat |
type of polyunsaturated fat that is required by the body
the numbering of the carbon omega starts from the methyl end or the end that is farthest from the carboxylic end |
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peptide bond |
bond formed between two amino acids by a dehydration reaction |
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dehydration reactions typically require what? how does this compare to hydrolysis reactions? |
require energy to form bonds
release energy by breaking bonds |
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give an example of an unbranched polysaccharide |
cellulose |
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give an example of a highly branched polysaccharide |
starch |
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pros & cons of storing glucose as glycogen or starch |
con: -less accessible for metabolism
pros: -prevents from leaking out of cell -less osmotic pressure, preventing excess water uptake |
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what kind of sugars are aldose & ketose? |
glucose & galactose are aldoses fructose is a ketose |
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Which categories of amino acid would you expect to find on the surface of a soluble protein? |
polar & charged amino acid residues (the remainder after peptide bond formation) |
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Which categories of amino acid would you expect to find on the interior of a soluble protein? |
nonpolar (e.g. amino acid side chains) |
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What distribution of amino acids would you expect to find in a protein embedded in a lipid bilayer? |
-nonpolar & hydrophobic amino acid side chains associate with the hydrophobic tails of phospholipids -polar & charged amino acid side chains interact with the polar head groups or with the aqueous solution |
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A mutation occurs, and a cytosine is replaced with adenine. What impact do you think this will have on the DNA structure? |
Adenine is larger than cytosine and will not be able to base pair properly with the guanine on the opposing strand. - this will cause the DNA to bulge >DNA repair enzymes may recognize the bulge & replace the incorrect nucleotide |
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Dehydration synthesis leads to the formation of |
polymers & water |
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What reaction takes place during the breakdown of polymers? |
hydrolysis |
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Examples of monosaccharides |
fructose glucose galactose |
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cellulose and starch are examples of |
polysaccharides |
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plant cell walls contain what in abundance? |
cellulose |
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lactose is a disaccharide formed by the formation of a ________ bond between glucose & _________. |
glycosidic galactose |
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phospholipids are important components of what? |
plasma membrane of animal cells |
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monomers that make up proteins are called what? |
amino acids |
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the α helix and β pleated sheet are part of which protein structure? |
2ndary |
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T/F A nucleotide of DNA may contain: ribose, uracil, & a phosphate group |
F |
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T/F A nucleotide of DNA may contain: deoxyribose, uracil, & a phosphate group |
F |
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T/F A nucleotide of DNA may contain: deoxyribose, thymine, & a phosphate group |
T |
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T/F A nucleotide of DNA may contain: ribose, thymine, and a phosphate group |
F |
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Why are biological macromolecules considered organic? |
they are carbon-based |
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Describe the similarities and differences between glycogen and starch. |
- both polysaccharides - both storage forms of glucose > glycogen stored in animals in liver and muscle cells > glycogen is a single type of highly branched molecule > starch is stored in the roots, seeds, and leaves of plants >starch has 2 forms: 1) amylose (unbranched) 2) amylopectin (branched) |
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Why is it impossible for humans to digest food that contains cellulose? |
digestive enzymes are unable to sever the β 1-4 linkages between glucose monomers & humans lack additional specialized flora to help |
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explain at least 3 functions that lipids serve in plants and/or animals |
1) storage of energy in animals 2) insulation 3) waxes protects plant leaves & prevents animal fur from moisture 4) phospholipids & steroids in cell membranes |
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Explain what happens if even one amino acid is substituted for another in a polypeptide chain. Provide a specific example. |
A change in gene sequence can lead to a different amino acid being added to a polypeptide chain This causes a change in protein structure and function e.g. in sickle cell anemia, the hemoglobin β chain has a single As substitution -- glutamic acid in position 6 is substituted by valine |
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Describe the differences in the four protein structures. |
1st - specific AA sequence 2nd - local folding 3rd - overall 3D structure 4th - when 2 or more polypeptides combine to form the complete protein structure |
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triglyceride |
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cholesterol |
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Cortisol |
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Amino acid |
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primary protein structure |
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secondary protein structure |
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tertiary protein structure |
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quaternary protein structure |
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