Chapter 3: Lipids, Carbohydrates, and Nucleic Acids Flashcards
Polymers from via _________________(1). Polymers break via _________________(2)
(1) Condensation
(2) Hydrolysis
What is dehydration/condensation?
The removal of water to from a covalent bond between monomers
What is hydrolysis?
The addition of water to break a covalent bond between monomers in a polymer
What are macromolecules? How do they form?
Large molecules prevalent in all organisms
Includes Lipids, carbohydrates, nucleic acids, proteins
Formed by endergonic condensation reactions that form covalent bonds between smaller molecules
Is the formation of macromolecules exergonic or endergonic?
Endergonic
Draw a hydroxyl functional group.
refer to notes
Draw a phosphate functional group.
refer to notes
Draw a carboxyl functional group.
refer to notes
Draw a amino functional group.
refer to notes
What are lipids defined by? What are some example of lipids?
Their insolubility in water
Ex. fats, oils
Are lipids hydrophobic or hydrophilic? Why?
Lipids are hydrophobic because of their many non polar covalent bonds
Contain mostly C—C and C—-H npon polar bonds, which have high schemical-bond energy.
What is the melting temperature of lipids determined by?
The size and how closely the molecules pack together(van der Waals interactions hold them together
What is a triglyceride?
Fats and oils, made of three fatty acids and one glycerol
What is a fatty acid?
a fatty acid is a carboxylic acid with a carboxylic acid consisting of a hydrocarbon chain and a terminal carboxyl group, which is either saturated or unsaturated.
What is glycerol?
A 3 carbon compound
What is a saturated fatty acid? What is the state at room temp?
All bonds between carbon atoms are single; they are saturated with hydorogens; pack together tightly; solid at room temp
What is an unsaturated fatty acid?
One or more double bonds between carbons; causes kinks in the chain and prevent molecules from packing together tightly; liquid at room temp
ex. coconut oil
How to compare the melting points of unsaturated vs saturated?
The more saturated something is, the higher its melting point
If something is 50% saturated and 50% unsaturated, it will be a solid
What is a lipoprotein? What is its purpose?
With certain proteins, phospholipids can form single-layer spheres with hydrophobic interiors and hydrophilic exteriors.
Lipoproteins are used for transporting lipids in aqueous solutions, such as triglycerides and cholesterol in the blood.
Is cholesterol a lipid?
Yes, it is a type of fat
It helps with fluidity and strength
What are some lipid functions?
Membranes, cholesterol, hormones(ex. sex hormones like estrogen and testosterone)
Is a phospholipid hydrophobic or hydrophilic?
It has a hydrophilic head and a hydrophobic tail
What are carbohydrates?
Linked carbons bonded to functional groups containing O and H, such as hydroxyl
What are lipids? What are the monomers of lipids?
Fats are a class of lipids containing two kinds of monomers, fatty acids, and glycerol.
Fatty acids are amphipathic. What does this mean?
a chemical compound containing both polar (water-soluble) and nonpolar (not water-soluble) portions in its structure.
Is a triglyceride hydrophobic or hydrophilic?
Hydrophobic
Are phospholipids amphipathic?
yes
Draw a phospholipid
refer to notes
What are simple sugars?
Carbohydrates with 12 or fewer carbons
What are monosaccharides?
Five or six carbons, usually in a ring(pentoses and hexoseS)
What is a disaccharide? What bond are they connected by?
Two monosaccharides linked by a glycosidic bond.
Mono and disaccharides can be ____________________(1) to proteins or lipids, modifying their ____________________(2)
(1) covalently bonded
(2) solubility and function
What is the format for naming glycosidic bonds?
(alpha/beta) (numbers) (glycosydic/peptidyl) bond
How to know if something is alpha or beta?
if the oxygen’s flip flop in position –> beta
if the oxygens don’t flip flop –> alpha
What is an oligosaccharide? What bond are they connected by?
Three to 10 monosaccharides joined by glycosidic bonds
oligosaccharides sometimes bind to proteins and lipids on cell membranes. What is the function of this?
they function as recognition signals
What are polysaccharides?
Polymers of hundreds to thousands of monosaccharides
Know how to number carbons in a sugar
the carbon hanging in the breeze has the highest numerb
What are linear chains of polysaccharides?
Monomers attached via 1,4 glycosidic bonds; branched chains are attached via 1,6 glycosidic bonds
Give examples of linear polysaccharide chains. Give examples of branched polysaccharides.
Linear: cellulose and chitin
\branched: starches, glycogen
What are nucleic acids?
Polymers that store, transmit, and express hereditary(genetic) infromation
includes DNA(deoxyribonucleic acid) and RNA(ribonucleic acid)
What are the monomers of nucleic acids?
Nucleotides, which contain a pentose sugar + N-containing base + phosphate grup
What is a nucleoside?
Pentose sugar + N-containing base
What pentose sugars do DNA and RNA conaitna?
DNA: deoxyribose(has just the H
RNA: ribose(had the OH, which is very reactive)
What is a pyrimidine and purine?
Pyrimidine: single ring
purine: double rings
Which bases are pyrimidines?
C, U, T, P
(cutie py)
Which bases are purines?
A G
Pure as gold
Nucleic acids grow in the _________________(1) direction.
(1) 5’ to 3’
Nucleotides bond in _________________(1) to form __________________(2) bonds.
(1) condensation reactions
(2) phosphodiester bonds
What are oligonucleotides?
Have up to 20 monomers, mostly RNA moleucles
What are polynucleotides?
composed of several nucleotide monomers with covalent bonds in a chain.
RNA is ______________(1) and DNA is __________________(2). IN DNA, the two strands come together by __________________________(3).
(1) single stranded
(2) double stranded
(3) complementary base apriing
What are the complementary base pairs?
A and T(or U)
G and C
The two DNA strands run _______________(1), which means they run in opposite directions. The funds of the ladder are formed by _______________(2) and the sides of the ladder are formed by _______________(3)
(1) antiparallel
(2) hydrogen-bonded bases
(3) sugar-phosphate groups
The bonds holding the two strands of DNA together are _______________(1). Base pairs can be separated with only a _______________(2)
(1) hydrogen bonds
(2) small amount of energy
RNA is usually single stranded but often ______________________________(1). The double strand regions give the molecule a 3-D shape that affects how it interacts with other molecules.
(1) folds back on itself to form short double-strand region
What is transcription?
Information encoded in DNA base sequences is used to synthesize RNA
What is translation
Information in RNA base sequences is used to synthesize proteins
What are genes?
DNA sequences that encode specific proteins and are trasncribed into RNA
What is the genome?
Complete set of DNA in a. living organism
List the four macromolecules int eh quantity in which they appear most in the body.
proteins>nucleic acids>carbs>lipids
What is cystic fibrosis caused by?
problems with one protein
What are the monomers of proteins?
Amino acids
What is the structure of amino acids?
A central carbon atom(the alpha carbon) connected to an amino group(NH2 or NH), a carboxyl group(COO-), a hydrogen atom, and a side-chain(R group)
Amino acids are linked together by ___________________(1) to form a protein.
(1) peptide bonds
The amino terminus is known as the _______________(1). The carboxyl terminus is known as the _______________(2). New amino acids are always added to the _______________(3) of a growing chain.
(1) N- terminus
(2) C-terminus
(3) c-terminus
What are the four categories of amino acids?
- Polar and charged
- Polar and uncharged
- Nonpolar(S-CH3 is non polar)
- special cases
What are the three special cases that should be memorized?
Cysteine(CH2 - SH)
Glycine(just an H)
Proline(3(CH2))
A chain of interconnected amino acids will not remain linear in aqueous solution; it will __________(1) into an energetically more stable structure.
(1) fold
The folded structure seeks to minimize exposure of non polar amino cid side chains to surrounding water while maximizing exposure of polar and charged groups. Non polar side chains are largely hidden in the interior of a folded chain.
The folded structure of a protein that is biologically active is called _______________(1).
(1) the native structure
What is protein denaturation?
Denaturations refers to the disruption of the folded structure of a protein. Heat, chemicals, pH changes, etc. can disrupt weaker bonding interactions in a bonding.
Give some examples of diseases that are caused by misfolded or aggregated proteins.
- ALzheimer’s, cystic fibrosis, Gaucher’s disease, Huntington’s disease, Parkinson’s disease, sickle cell anemia
What constitutes a protein backbone?
All of the amino acids linked together but not counting their side chains(R groups)
What is a polypeptide chain?
One string of amino acids
What is a protein?
Composed of one or more polypeptide chains
What is the primary structure of a protein?
The sequence of amino acids in a single polypeptide chain
Have covalent peptide bonds that link amino acids
What is secondary structure?
Regular, repeated spatial patterns of local regions of a polypeptide chain, folded by hydrogen bonding.
Can have beta pleated sheets or alpha helixes
Hydrogen bonds indicated with dotted or dashed line
What is the tertiary structure?
Entire polypeptide chain is bent and folded upon itself; results in the definitive 3d shape
beta pleats and alpha helixes connected by COVALENT disulphide bridges
have disulfite bridge(only covalent bonds), ionic bonds, hydrogen bonding, hydrophobic interactions between r groups
What is quaternary structure?
Two or more polypeptide chains(subunits) come together to forma. larger structure. Typically stabilized by non-covalent interactions, but can also occur through disulphide bonds.
have disulfite bridge(only covalent bonds), ionic bonds, hydrogen bonding, hydrophobic interactions between r groups
What are catalysts?
Substances that speed up reactions without being permanently altered(don’t get used up)
Enzymes are biological catalysts. How do they work?
Enzymes temporarily bind to their substrates(reactants) to catalyze a chemical reaction. Substrates bind in the enzymes active site. they lower the activation energy needed to reach transition state
What is a noncompetitive inhibitor?
A noncompetitive inhibitor binds at a site distinct from the active site, affecting enzyme shape and function. it prevents substrate binding or slows the reaction rate
The site where the inhibitor binds is called the _______________(1)
(1) allosteric site
