THE MCAT-BIO 1 Word Scramble
|
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Question | Answer |
Phase contrast microscope | view live organisms but can't focus on certain structures |
electron microscope | use beam of electrons to focus on dead organism in detail |
In centrifugation, what types of organelles will be on top / bottom? | mitochondria & lysosomes on top ribosomes on bottom |
What do prokaryotes have instead of nucleus? | nucleoid |
What is plasmid? | -small circular pieces of DNA that carry genetic info -replicate independently and can be passed from one prok to another |
Do prokaryotes have cell membrane? | yes |
What is the benefit of membrane-bound organelles? | separates bio. reactions and functions into separate compartments |
What do transport proteins do? | allow polar molecule and ions to move in and out of cell |
What is nuclear membrane? | double membrane to separate nucleus from cytoplasm? |
What is nucleolus and where is it located? | -rRNA synthesized here -located inside nucleus |
How is genetic material organized? | DNA --> genes --> wound around histone proteins --> chromatid --> chromosome |
What do free ribosomes make? | make proteins in cytosol |
What do bound ribosomes make? | -proteins that directly insert into the ER -px are used within plasma mem or expelled from cx |
What does smooth ER do? | -lipid & steroid synthesis -detox drugs and poison |
What does rough ER do? | involved in producing transmem px or secreted px |
What do lysosomes do? | use hydro |
Where are the proteins used in peroxisomes produced? | cytosol --> mature polypeptide made and then attaches to peroxisomes through a signal |
Where do peroxisomes come from? | ER |
Where do lysosomes come from? | golgi |
What do lysosomes do? | -breakdown cellular waste -apoptosis -digest macromolecules from phagocytosis |
What do peroxisomes do? | -beta-oxidation -lipid biosynthesis -catalase to convert H2O2 to water -detox rxns. in liver |
What is beta-oxidation? | process where fatty acids are broken down in mito to make acetyl coA |
How are mito. semiautonomous? | have their own genes and replicate independently of nucleus via binary fission |
Where are the enzymes for cellular respiration located? | mito. matrix |
What are microfilaments used for and what are they made of? | -muscular contraction and cytokinesis -actin |
What are microtubules used for? | -chromosomal separation during meiosis and mitosis -cilia and flagella -intracx transport of organelles and vesicles |
What are lysosomal storage diseases? | accumulation of carbs, lipids, and proteins from failure of production of an enzyme within lysosome to break down |
hypotonic | -conc. of solutes inside cell is higher --> gain water |
hypertonic | -conc. of solutes outside cell is higher --> lose water |
isotonic | -conc. of solutes is equal --> no net movement |
What are viruses? | nucleic acid surrounded by protein coat |
Difference between the way bacteria and virus attack cells? | Bacteria never enter cell while viruses always enter cell to replicate |
What are lipids made of? | -carboxylic acid + alcohol --> ester link (even number of carbons and max # is 24 in humans) |
Saturated vs. unsaturated | saturated has single / unsaturated has double bond |
amphipathic | polar and nonpolar end (that's why phospholipids are good for cell membrane) |
What is glycerol? | 3-carbon backbone found in lipids |
Where are glucolipids found? | membrane of myelinated cells in human nervous system |
Formation of lipids requires what kind of bond? | ester linkage |
Steroids | 4-ringed structures |
Terpenes | Vitamin A |
Eicosanoids | -signaling molecules involved in inflammation and immunity -include prostaglandins and leukotrienes |
What does aspirin inhibit? | synthesis of prostaglandins |
How are lipids transported in the body? | lipoproteins |
Which lipoprotein has the highest lipid percentage? | chylomicrons |
Name all parts of an amino acid | amino (NH2), carbonyl (COOH), hydrogen, R group |
Can a single protein have both alpha helix and beta pleated sheet? | yes! |
Tertiary structure | secondary structure folds upon itself |
How does proline affect peptide structure? | creates turns that disrupt helix and beta sheet |
quaternary structure | two or more polypeptides |
What structures does denaturing proteins affect? | secondary, tertiary, quaternary |
What are 5 forces that create tertiary structure? | -H-bonds -hydrophobic side chains (pushed to center) -electrostatic interactions btwn acidic and basic side chains -van der Waals -covalent disulfide bonds |
cytochrome | membrane bound hemopx that have a heme and carry out ETC |
proteoglycans | proteins that are heavily glycosylated |
glycoproteins | carbs covalently attached to proteins |
Basic amino acids (3) | histidine, lysine, arginine |
acidic amino acids (2) | glutamic acid and aspartic acid |
How are alpha and beta glucose different? | -alpha glucose has -OH on axial and equatorial -beta glucose has -OH on both axial / equatorial |
If cell as enough ATP, what happens to glucose? | becomes glycogen |
Where is glycogen found? | muscle and liver cells |
How does the liver regulate blood glucose? | glucose --> glycogen --> glucose |
How is glucose absorbed into bloodstream? | 1.) against a concentration gradient with secondary active transport with sodium 2.) facilitated diffusion (increases with insulin) |
What has beta / alpha links | cellulose / everything else |
3 components of nucleotides | -5-carbon sugar -nitrogenous base -phosphate group |
Phosphodiester bond | phosphate of one nucleotide and 3rd carbon of pentose of other nucleotide |
What do minerals do? | transport substances entering and exiting the cell through electrochemical gradient |
activation energy | energy required to break bonds before new bonds can form |
Are enzymatic reactions reversible? | yes |
What do enzymes do? | -lower Ea for forward and reverse rxns -increase rate of reaction (increase rate constant k) -select which reactions will occur |
What don't enzymes do? | -not consumed in a rxn or altered -do not start rxns that wouldn't normally occur |
Induced Fit Model | Enzyme and substrate change shape --> increases specificity and helps rxn proceed |
Substrate squeezing in / release is endothermic / exothermic? | endothermic / exothermic |
Most enzymes function around which pH | 7.4 |
Do enzymes affect Keq or delta G? | NOOO --> no thermodynamics only kinetics! |
Enzymes can be protein and...? | RNA --> ribosome |
transition state analog | -resemble transition state and can act as competitive inhibitor |
turnover number | -when enzyme is completely saturated with substrate, number of substrate molecules converted to product |
When substrate conc is small and enzyme conc is constant, velocity is proportional to substrate conc. as ______ order? | first |
When substrate conc. is large and velocity is independent of substrate conc as ____ order? | zero |
What is Km? | point where 1/2 enzyme's active sites are full and rxn rate is 1/2 max value --> enzyme affinity for substrate |
lysozyme | -enzyme that hydrolyzes glycosidic bonds in bacterial cell walls |
ribonuclease | -catalyzes hydrolysis of phosphodiester in RNA |
carboxypeptidase | -digestive pancreatic enzyme to cleave carboxy terminal peptide bond |
chymotrypsin | -hydrolysis of ester and peptide bonds |
peptide --> | amine and acid |
ester | alcohol and acid |
What is Vmax proportional to? | enzyme concentration |
What does low Km mean? | high affinity for substrate |
What does high Km mean? | low affinity for substrate |
When substrate concentration is less than Km, changes in [s] will greatly affect rxn rate T / F? | True |
what pH does pepsin function / pancreatic enzymes | 2 and 8.5 |
Co-factors | 1.) bind substrate to enzyme 2.) stabilize enzyme in active conformation |
Apoenzyme / holoenzyme | enzyme w/o cofactor & enzyme with co-factor |
What are 2 types of co-factors? | co-enzymes and metal ions |
What are coenzymes? | prosthetic groups or cosubstrates (reversibly bind to enzyme - ATP) |
Irreversible inhibitors | -covalently bind and permanently disrupt function at active site |
Competitive Inhibitors and how to overcome? | -bind reversibly with noncovalent bonds -increase conc. of substrate (Km increases) |
Noncompetitive Inhibitors and how to overcome? | -bind noncovalently to site other than active site -change conformation of enzyme -increase enzyme conc. |
How are noncompetitive different than competitive? | -do not prevent substrate from binding -do not resemble substrate so can act on more than one enzyme -bound far or near active site |
What do Vmax and Km depend on? | Vmax - enzyme conc Km - substrate conc |
What do competitive vs. noncompetitive inhibitors do? | competitive - raise Km, do not change Vmax noncompetitive - lower Vmax, do not change Km |
Do noncompetitive inhibitors affect substrate binding and enzyme affinity for substrate? | NO --> that's why Km stays the same |
Can enzyme catalyze reaction as long as noncompetitive inhibitor is bound? | NO --> substrate can still active site though |
Vmax vs. Km graph: competitive shift right | apparent Km increases, Vmax no effect |
Vmax vs. Km graph: competitive shift left | apparent Km decreases, Vmax no effect |
Allosteric enzyme | one active and one regulatory site where inhibitors and activators can bind |
How do allosteric inhibitors / activators act? | change quaternary structure |
Are allosteric regulators noncompetitive inhibitors? | not necessarily |
Negative / positive feedback inhibition? | allosteric inhibitor / activator act on reaction |
Irreversible covalent modification example | zymogens are irreversibly activated |
Reversible covalent modification example | phosphorylation |
kinase vs. phosphatase | enzyme that phosphorylates vs. enzyme that dephosphorylates |
hexokinase | phosphorylates glucose |
Antitrypsin | inhibits trypsin and prevents digestive enzymes from digestinb doy |
Humans can synthesize NAD as long as there is what amino acid in diet? | Trp |
What is FAD derived from? | Vitamin B2 |
Where does ATP energy come from? | loose and covalent bonds of phosphate groups |
NAD, NADPH, FAD are _____ agent and are ____ during ____ reactions | oxidizing / reduced / catabolic |
NADH, NADPH, FADH are _______ and are ______ during _____ reactions. | reducing / oxidized / anabolic |
Where does glycolysis occur and what does it produce? | -cytosol -2 pyruvate and 2 NADH |
substrate-level phosphorylation | formation of ATP without intervention of ETC |
What is the main importance for fermentation and how much ATP? | -regenerate NAD+ to continue glycolysis anaerobically (aerobically, NAD+ regenerated through ETC) -2 ATP |
What can pyruvate turn into with fermentation? | 1.) ethanol/CO2 & 2 NAD+ 2.) lactic acid & 2NAD+ |
Where does pyruvate decarboxylation take place and what does it produce? | -mito matrix -2 acetyl coA, 2 CO2, 2 NADH |
How do pyruvate and NADH pass into mito? | -pyruvate and NADH can pass through outer mem via facilitated diffusion through porin px -inner mem, pyruvate can move in but NADH may need hydrolysis of ATP |
What does TCA produce for each turn of cycle? | 1 ATP, 3 NADH, 1 FADH2, 2 CO2 |
How to begin TCA cycle? | transfer 2C from acetyl coA combines with oxaloacetate (4C) to create citrate (6C) |
When are ketone bodies produced? | levels of acetyl coA exceed TCA capacity |
Where is ETC located and what is it | series of 4 large metallopx bound to inner membrane |
Where is ETC and OP located for prokaryotes? | Proks don't have mito so ETC and OP occurs in inner plasma mem |
How are protons from inner membrane pumped to intermem? | energy from ETC pumps protons through peremases |
oxidative phosphorylation | creation of ATP through ETC |
How many ATP does NADH and FADH2 create? Why does FADH2 create less? | -3 ATP / 2 ATP -electrons from FADH2 travel shorter distance |
What is final electron acceptor and what is it reduced to? | O2 and water |
Is ATP synthase reversible T/F? | TRUE - can make NADH |
Is inner membrane permeable to protons? | NO |
Uncoupling protein | -mito inner mem px that dissipates H+ gradient to block OP -energy used to generate heat instead of ATP -increase permeability of inner mito mem so protons pumped out return |
Pentose phosphate pathway | 1. generates NADPH --> f. a. synthesis 2. produces ribose --> nucleotide synthesis |
Difference between NADP and NAD? | NAD is used in catabolism while NADP is used in anabolism |
What is largest class of human mutations? | sex-linked deficiency in glucose-6-phosphate dehydrogenase -don't make NADPH / reduced glutathione (mosquitoes need to survive) |
Gluconeogenesis | lactate goes to liver and converted to glucose to return to muscle -net loss of ATP to make this happen |
What are 3 steps for f.a. oxidation? | transport to mito, beta oxidation, ETC |
How do free fatty acids travel? | bound to albumin |
What activates lipases for beta oxidation? | glucagon and epi |
What creates ammonia? | deamination of a.a. |
What is chief/second nitrogenous waste of mammals and how is it excreted? | urea/uric acid and kidneys |
What causes kidney stones? | uric acid |
What is glyceraldehyde 3-P also known as? | PGAL |
Can glycerol backbone of fats enter glycolysis? | YES --> becomes PGAL |
How can amino acids be converted to TCA cycle substrate? | -deaminated in liver -converted to acetyl coA |
How can glycogen be converted to glycolysis intermediate? | glycogen --> glucose 6-P for glycolysis |
Do muscles have glucose-6-phosphatase? | NO --> glycogen stored is for muscle use only |
Does liver have glucose-6-phosphatase? | YES --> glucose can be shared with other cells |
Final products of aerobic respiration? | -36-38 ATP -2 FADH2 -10 NADH |
What are the irreversible reactions of glycolysis? | -creation of glucose 6-P, creation of fructose 1,6-bisP, creation of pyruvate |
What reaction does phosphofructokinase catalyze? | fructose 6-P --> fructose 1,6-bisP |
What inhibits phosphofructokinase for glycolysis regulation? | -high ATP, high H+, high citrate |
What promotes phosphorfructokinase activity? | -low ATP, high AMP |
What do prokaryotes lack? | true nucleus |
Why don't enzymes change the Keq of a reaction? | lowers activation energy for both forward and reverse reactions |
Enzymes affect the _______ of a reaction, NOT the ________. | kinetics / thermodynamics |
Enzymes can be specific enough to distinguish between steroisomers. True or False? | True |
Enzymes in the body can be _____ or ______. | protein or RNA (ribosome) |
Non-competitive inhibition decreases? | Vmax |
Does non-competitive inhibition change the amount of substrate needed for Vmax? | NO |
Can you overcome non-competitive inhibition by adding more substrate? | NO |
Where does the oxygen from the water produced in aerobic respiration come from? | oxygen you breathe in |
Where does carbon in glucose end up in? | carbon dioxide |
Where doe soxygen in glucose end up in? | carbon dioxide |
When electrons are passed from NADH to O2 in ETC, what is released? | energy |
What does FADH2 skip in the ETC which creates its lower energy? | skips FMN and passes to Coenzyme Q |
Energy released from ETC generates what? | proton gradient which drives ATP synthesis |
What inhibits ETC? | antibiotics, cyanide, carbon monoxide |
Where does beta oxidation occur? | matrix of mitochondria |
Where does ester hydrolysis occur and waht does it become? | -cytosol -free fatty acids and glycerol |
How is fatty acid activated for beta oxidation? | -With ATP, f.a. is "activated" by CoA (becomes thioester) |
What happens during beta oxidation? | -breaks down fatty-coA, 2 carbons at a time, to make acetyl coA |
What does beta oxidation produce? | acetyl coA, FADH2, and NADH |
What is nitrogen converted to in humans? in desert animals, birds, and reptiles? | -urea -uric acid |
For px metabolism, carbon in a.a. is converted to? | pyruvate, acetyl coA, or any other metabolic intermediate depending on a.a. |
What is fat for carbon products from a.a. metabolism? | - go into Kreb's -starting material for gluconeogenesis |
What do bacteria lack? | no nuclear membrane, mitotic apparatus, golgi, ER, mito, chloroplasts |
How do prok pull replicating cells apart w/o mitotic apparatus? | prok cytoskeleton pulls replicated DNA apart |
bacteria flagella is made of ________. eukaryotic flagella is made of ________. | flagellin / microtubules |
What powers bacterial flagella? Eukaryotic flagella? | -proton/sodium gradient -ATP |
What is motion of bacterial flagella? Eukaryotic flagella? | -rotation -whip like motion |
Describe fission. | DNA replicates, DNA attaches to cx mem as cx elongates, cytokinesis |
Defining characteristics of euks. | True nucleus, membrane-bound organelles, divide by mitosis |
What are 3 factors of mito according to endosymbiosis theory? | self-replicate, have own DNA, have own ribosomes --> all are different than host |
How do lysosomes work? | Wastes gets into a vacuole by endocytosis or phagocytosis -vacuole fuses with lysosome |
What is another name for smooth ER in muscles? | sarcoplasmic reticulum --> stores calcium |
What are the roles of smooth ER and rough ER in membrane biosynthesis? | -smooth ER - makes mem lipids -rough ER - makes transmembrane px |
How do transmem px / secreted px produced correctly? | -have signal sequence at beginning -ribo starts to make px with signal sequence first -signal recognition particle recognizes and drags to RER |
ER is connected to what? | nuclear membrane |
relationship between RER and golgi? | RER makes px --> modified in Golgi --> buds off Golgi and exits by exocytosis |
Where does glycosylation of px occur? | Golgi |
What does glycosylation do to px? | affect's px structure, function, and protect from degradation |
Fluid mosaic model | protein boats floating in sea of lipids |
The resting membrane potential is positive / negative? | negative |
gap junction | connect 2 cx and allow stuff to flow through |
tight jxn | glues cx together to form impermeable barrier |
desmosomes | -connects 2 cx together by linking cytoskeleton -mechanical strength, not impermeable barrier |
Microfilaments and intermediate filaments support cx shape by bearing _________. Microtubules support cx shape by bearing __________. | -Tension -Compression |
Where is kinetochore located? | point joining two sister chromatids |
What is a centrosome vs. centriole? | Centrosome = centriole plus matrix and is where microtubules originate |
Centrioles, microtubule organizing centers? | microtubules radiate out of these barrel shaped structures which are made of microtubules |
What are the stages of interphase? | G0, G1, S, G2 |
Formula for number of peptides that contain "n" amino acids? | n! |
What stabilizes 3-D structure of px | covalent bonds and noncovalent interactions |
What is endosymbiotic theory? | mito are descendents of prok engulfed by endocytosis into a vesicle lined with a euk mem. |
Inne rmem of mito is analogous to ____ of prok. | plasma membrane (has oxidative phos. enzymes) |
During starvation, what is broken down first, second, and last? | -carbs, lipids, body px |
What is the major microtubule organizing center? | centrosome |
How are the flagella in euk and prok different in structure? | -euk = 9+2 microtubules -prok = thin strand of flagellin px |
ANtibiotics that block translation by prok ribo but NOT euk ribo also block translation by_____? | mito ribo |
Most px used by mito are coded by ________ | nuclear DNA |
What is most common extracx matrix px? | collagen |
protease | enzyme involved in protein digestion |
isozymes | enzymes that differ in a.a. sequence but catalyze same reaction |
What is main metabolic produce of CO2? | TCA cycle |
Primary structure of proteins | linear sequence of a.a. held together by covalent peptide bonds |
Secondary structure of px | alpha helix or beta sheet |
Which organelles replicate independently of the cx? | peroxisomes and mito |
WHich is the a.a. capable of forming disulfide bonds? | cysteine |
What are the 2 nonpolar a.a.? | valine and alanine |
What are the 2 acidic a.a.? | glutamic acid and aspartic acid |
WHat are 3 basic a.a.? | arginine, histidine, lysine |
What does it mean to be membrane-bound? | -have double phospholipid membrane |
What are membrane-bound organelles? | mito, lysosome, nuclear envelope, ER, golgi bodies |
What do endosomes do? | intracx sorting organelles that deliver fats, px, and other materials to lysosomes fro degradation |
Microfilaments are associated with _____ while Microtubules are associated with _____. | -amoeboid mvmt. -phagocytosis |
What most resembles the golgi apparatus? | smooth ER |
Is the interaction between inhibitor and enzyme permanent in competitive inhibition? | NO --> transitory |
Do cx walls, spore coats, or capsules have lipid bilayer? | NO |
What does microtubule paralysis cause? | nerve degeneration and muscle weakness |
autophagy | lysosomes engulf and digest damaged/old intracx organelles |
phagosome | phagocyte + ingested material |
Are sodium channels open at rest? | NO --> ALWAYS CLOSED |
What channel majorly determines resting potential? | potassium |
What determines negative resting emmbrane potential? | closed Na/Cl channels and open leaky K channels |
Does simple diffusion rely on channels to transport molecules? | NO |
What determines the resting membrane potential? | leaky potassium chanels |
body tissue | group of similar cells |
organ | collection of several tissues |
Where are cilia located? | trachea/bronchi of respiratory tract, lumen of small intestine, fallopian tubes |
obligate anaerobes | absolutely unable to grow in oxygen |
facultative anaerobes | able to grow in presence in presence or absence of oxygen |
obligate aerobes | must have oxygen to survive |
According to Poiseuille's Equation, what creates faster velocity conduction? | increased radius, decrease in length F = r^4 / L |
Can ntm diffuse across cx membrane? | NO --> HYDROPHLIC |
Why does the axon terminal have lots of mito? | ntm exocytosis is an active process that requires a lot of ATP |
What are the non-membrane bound organelles? | microtubules, intermediate filaments, microfilaments, ribosomes |
Are myosin and actin microfilaments or microtubules? | microfilaments |
Is the esophagus part of the digestive or respiratory tract? | digestive |
What px structure is a heterodimer? | quaternary |
Does the retina require ATP to function? | YES |
What do uncouplers do to ETC? | decrease intermembrane acidity by dirupting H gradient |
When is BP reached? | VP is equal to atmospheric pressure |
Higher vapor pressure... | lower boiling point |
If OP is blocked, what will the body do instead? | increase ATP synthesis through glycolysis |
Does hyperpolarization cause inhibition or activation? | inhibition |
Where are muscarinic vs. nicotinic receptors found? | muscarinic - CNS nicotinic - PNS |
What type of rx are nicotinic and muscarinic? What system are they a part of? | cholinergic / PNS |
Where are a lot of ribosomes found in a neuron? | soma |
prokaryotic DNA | single, circular, uncoated, double stranded DNA molecule |
Created by:
507935299
Popular MCAT sets