7101 HSF EXAM 1

big mama flashcard deck

catabolism

exergonic rxn to break down molecules (releases energy)

anabolism

endergonic rxn to build up molecules (use energy)

what are the biological compounds?

amino acids = proteins

nucleotides = nucleic acids (DNA/RNA)

saccharides = carbohydrates (sucrose, glycogen, cellulose)

fatty acids = lipids (bio-membranes)

nucleotides play roles in ____________.

protein synthesis, energy, and cell signaling

what is a nucleoside?

sugar + base

(base = ATGC)

what is a nucleotide?

sugar(ribose/deoxyribose) + base + phosphate

(base = ATGC or UforT in RNA)

DNA and RNA subunits are joined by ___________ bonds.

phosphodiester

what special characteristic does the A (central) carbon of an amino acid have?

chiral/optical activity (except glycine)

describe the basic amino acid structure.

amino/basic group (N) + CHR + carboxylic acid group

amino acids run from the to terminus

N to C

what is an amphoteric molecule?

has both basic and acidic properties

what kind of isomers are proteins?

L isomers

what is the zwitterionic form of a molecule?

double ionized molecule

• (ex. in an amino acid: NH3+ and COOH-)

what is the isoelectric point?

net charge = 0

when pH increases, are molecules protonated or deprotonated?

pH inc, [H+] dec, deprotonation

when pH decreases, are molecules protonated or deprotonated?

pH dec, [H+] inc, protonation

what system do we use to maintain pH in the body?

bicarbonate buffer system (adds or removes H+)

what are the polar amino acids? charge at pH 7

neutral: SER, THR, ASN, GLN,

negative: ASP, GLU,

positive: ARG, HIS, LYS

other: CYS, TYR

which amino acid has a ring structure that causes bending in proteins?

proline

which amino acids (neutral) can perform sugar linkages?

SER, THR, ASN

what is an aliphatic molecule

one having a straight or branched structure

through what bonds are amino acids linked?

peptide bond (condensation rxn btwn C terminal of one aa to N of another)

what does pKa represent?

the dissociation constant of an acid

• large pKa = weak acid

• smaller pKa = stronger acid

at what pka values is buffering capability the greatest?

2 values: that of the amino (~9) and the carboxyl groups (~2)

(carboxylic should be lower pKa bc it is a stronger acid)

enzymes are made of what biomolecule?

proteins

what are the structure levels of proteins?

1. linear (can have disulfide bonds)

2. a-helix and b-sheets

3. folding and globular proteins

4. groups of tertiary proteins

____________ indicates the structure and function of a protein.

amino acid sequence

what are the categories of proteins?

• fibrous: collagens, elastins, ECM, and cytoskeleton

• globular: functional (polar surface, non-polar interior)

what are enzymes?

proteins (exception RNA) that accelerate rxns by lowering activation energy (not changing equilibrium). they are not consumed in the rxn

enzymes have specificity, what does this mean?

they are specific to a certain substrate, conform to its shape

how does the rate of a rxn relate to enzyme concentration?

linear (Vmax reached when all activation sites are saturated)

what does the Km value of a substrate represent?

affinity for substrate

what does a high Km value of an enzyme represent?

low affinity for substrate

what does a low Km value of an enzyme represent?

high affinity for substrate

how can enzyme activity be regulated?

the amount of enzyme (slow)

modifying enzyme activity (fast)

what is enzyme allosteric control?

change in activators/inhibitors

what are covalent modifications of enzymes (activate or deactivate enzyme)?

• peptide bond cleavage, phosphorylation (kinase adds, phosphatase removes)

what are the types of enzyme inhibitors?

• competitive

• noncompetitive

• uncompetitive

what are the properties of a competitive enzyme inhibitor?

• target the active site, lowers Km (inc substrate affinity)

• can be overcome by increasing [S]

what are the properties of a noncompetitive enzyme inhibitor?

• binds to non active site, lowers Vmax

• takes out enzymes

what are the properties of an uncompetitive enzyme?

• binds to ES complex, lowers Km and Vmax

what is the major function of carbohydrates?

supply energy through glycolysis and TCA cycle

what are the most common monosaccharides?

glucose, galactose, fructose

what are the most common disaccharides?

lactose, sucrose, maltose

what are the most common polysaccharides?

cellulose, starch, glycogen

what does an aldehyde on a carbohydrate look like?

HC=O

what does a ketose carbohydrate look like?

CH2OH

how do we name multicarbon chains? 3,4,5,6

triose, tetrose, pentose, hexose

which monomers are aldohexoses?

glucose, galactose, mannose

which monomers are ketoses?

fructose

in carbohydrates, the ________ of the end carbon can react with the ketone/aldehyde to form a _____________.

hydroxyl group, ring (hemiacetal)

what is the anomeric carbon?

helped form the hemiacetal, commonly displayed just to the right of the O in the ring. (Used for B/A naming)

what is the name for a 6 carbon ring?

pyranose

what is the name of a 5 carbon ring?

furanose

what is a reducing monosaccharide?

has a potential free aldehyde group

what disaccharides are reducing?

maltose and lactose

what disaccharides are nonreducing?

sucrose (1-2 bond)

review naming disaccharides

youtube

what are examples of simple sugar derivatives?

glucuronic acid and glycosaminoglycans (GAGS)

what is the basic structure/types of starch?

• smaller glucose polymer (200+)

• amylose: unbranched (a1-4 bonds)

• amylopectin: branched (a1-4 bonds w a1-6 branches)

what is the basic structure of glycogen?

• branched and compact, most abundant carb in mammals

• a1-4 bonds and a1-6 branches (like amylopectin)

what is the basic structure of cellulose?

• large glucose polymer (3000+)

• plant cell wall structure (b1-4 bonds)

what are the major functions of lipids?

energy storage, membranes, hormones, vitamins, and messengers

fatty acids are used for fuel and building blocks. how do we number the carbon chain?

C1 is double bonded to an O, count out from there

• A carbon is C2, B C3, and omega is the final carbon in the chain

what molecules store and transport fatty acids? They are the most abundant lipid.

acylglycerols: esterification of F.A. and glycerol, they are hydrolyzed by lipases

what is the basic structure of a phospholipid?

fatty acid tails: one saturated, one unsaturated

glycerol backbone

phosphate bonded to an alcohol by a phosphodiester bond

do saturated fatty acid chains have double bonds?

no (think saturated with hydrogens)

do unsaturated fatty acid chains have double bonds?

yes

where do we find cholesterol, the most abundant sterol in animal tissue?

free form in membranes

esterified in non membranes

Briefly describe the organization of cells and tissues?

cells are connected to the ECM via cytoskeleton, tissues are held together by ECM, collagens, glycoproteins, and proteoglycans

eukaryotic cells are compartmentalized, this creates a nucleus, and ___________. The aqueous area is called ________.

cytoplasm, cytosol

which cell part is responsible for RNA synthesis, has an outer and inner membrane, and is continuous with the ER?

nucleus

which organelles are non membranous and responsible for protein synthesis?

Ribosomes (60s,40s subunits in eukaryotes)

what organelle is responsible for protein synthesis, folding, modification and movement?

rough ER (modifications include disulfide bonds and glycosylation)

what organelle is responsible for the synthesis of lipids and steroids, carb metabolism, drug detox, and calcium storage (muscle)?

smooth ER

what organelle is responsible for post translational modifications, protein sorting and packaging?

golgi body

what portion of the golgi apparatus faces the rough ER, what part faces the cell membrane?

cis, trans

where are coatomer proteins found, what do they do?

• transport proteins in the golgi

• (COP2)= anterograde (forward transport)

• (COP1)= retrograde (backwards transport)

what cellular components act as intermediate sorting vesicles for endocytosed material?

endosomes

what cellular components digest endocytosed material? (endosome origination)

lysosomes

what process does the mitochondria use to generate ATP.

oxidative phosphorylation

explain the general structure of the mitochondria.

outer mem, inner mem space, inner mem (cristae inc surface area)

the inner membrane matrix contains __________, which help hold together the APT synthases.

cardiolipin

the ________ membrane of the mitochondria is permeable, the ____________ membrane is impermeable.

outer, inner

during cell-cell attachment, the two plasma membranes up against each other giving a _________ appearance.

trilaminar

the glycocalyx contains:

glyco-lipds/proteins, and proteoglycans

the plasma membrane is bilayered, it has an inner (____ face) and outer leaf (____ face)

P, E

what enzyme flips molecules in the bilayer from one leaflet to another?

flippase

if flippase is dysfunctional, what can be triggered?

apoptosis

what are the types of endocytosis?

phagocytosis (eating), pinocytosis (drinking), and receptor mediated

what are the types of exocytosis?

constitutive, and regulated

what kinds of endo/exocytosis use clathrin coated pits?

receptor mediated endo, regulated exo

what are the major types of active transport?

coupled transport (symport/antiport)

what are the major types of passive transport?

simple and facilitated diffusion

what are the functions of the cytoskeleton?

structure (cell shape change), material transport, cell attachment

what are the major components of the cytoskeleton?

microfilaments, intermediate filaments, microtubules, thick filaments

microfilaments are made of _____.

actin

microfilaments have 3 classes of actin, what are they?

• a and B - muscle actin

• y - non muscle actin

what are the microfilament monomers that coil to form F actin bundles?

G actin

what are the functions of microfilaments?

movement by interaction w myosin and adhesion through other binding proteins