Bisc 160 Final - Summer 2015
In PCR, __ creates single-stranded DNA template molecules a. DNA polymerase b. primer c. helicase d. dNTPs e. heat
E
The outer membrane of the nuclear envelope is continuous with the membrane of the __ and is usually covered with attached ribosomes. a. cell wall b. endoplasmic reticulum c. plasma membrane d. nucleolus e. chromatin
B
Gene expression in bacteria is regulated primarily by: a. protein modifications b. controlling the rate of DNA replication c. transcriptional control d. protein degradation e. translational control
C
Translation is initiated at the __. a. AUG codon b. anticodon c. UAG codon d. promoter e. downstream sequence
A
Exons in pre-mRNA: a. are spliced out of the message b. are part of the mature mRNA c. protect pre-mRNA from enzyme degradation d. are transcribed into protein
B
The first step in carbon fixation involves the addition of a CO2 molecule to a molecule of: a. G3P b. NADPH c. water d. ribulose biphosphate
D
Which of the following conditions does not favor plants using a C4 pathway (as compared to C3 plants)? a. lower than average temperatures b. growing in bright sunlight (instead of shade) c. lower C02 levels d. higher light intensities e. actually, none of these would be favorable for a C4 plant
A
Which pair matches the correct macromolecule with the bond that joins its subunits? a. triacylglycerol--glycosidic linkage b. protein--ester linkage c. steroid-- peptide bond d. nucleic acid-- phosphodiester linkage e. polysaccharide-- peptide bond
D
What does oxidative decarboxylation of two pyruvates yield? a. 1 fructose-1,6-biphosphate b. 2 glucose molecules c. 2 ATP + 4C02 + 2 NADH d. 2 G3P e. 2 acetyl CoA + 2 CO2 + 2 NADH
E
What is the role of the oxygen molecules required for aerobic respiration? a. to store high energy electrons to pass to complex I of the electron transport chain b. to produce CO2 c. to accept electrons directly from either NADH of FADH2 d. to form ATP e. to accept the low energy electrons at the end of the electron transport chain
E
Which of the following is a key component of the cytoskeleton? a. DNA b. centrosome c. endoplasmic reticulum d. ribosomes e. microtubules
E
Which of the following statements concerning enzymes is FALSE? a. most enzymes are highly specific b. some enzymes require cofactors c. each enzyme has an optimal pH d. each enzyme as an optimal temperature e. most enzymes are RNA molecules
E
Which reactant of aerobic respiration is oxidized? a. energy b. water c. glucose d. carbon dioxide e. oxygen
E
Which substances correctly identifies as reactant in the following chemical equation? C02+H20 --> H2CO3 a. carbon b. oxygen c. carbonic acid d. hydrogen e. water
E
Why is it important for DNA to be copied before cell division? a. the daughter cells do not need proteins b. the daughter cells need extra copies of the genetic information present in the parent cell c. the nucleus does not contain enough room for extra DNA d. the daughter cells must be polyploid e. genetic information must be transmitted to the daughter cells
E
Generally speaking how many "turns" of the Calvin cycle are needed to ultimately gain one molecule of glucose? a. 6 b. 1 c. 3 d. 12
A
How can we identify a particular element? a. by its number of protons b. by its number of electrons c. by its number of neutrons d. by its amount of energy levels e. by its shape of valence shells
A
If a cell has an abundant supply of ATP, acetyl CoA may be used: a. for fatty acid synthesis b. to enhance fermentation c. to convert pyruvate into glucose d. to enhance oxidative metabolism e. none of the above
A
In a prometaphase cell, the: a. nuclear envelope is visible with the light microscope b. nuclear envelope disappears c. duplicated chromosomes become visible with the light microscope d. mitotic spindle is beginning to assemble e. spindle fibers pull chromosomes to opposite sides of the cell
B
Why is DNA able to store large amounts of information? a. its nucleotides can be arranged in a large number of possible sequences b. it is composed of 20 different nucleotides c. its bases can be altered from purines to pyrimidines d. it is capable of assuming a wide variety of shapes e. its sugars and phosphates can be arranged in many different sequences
A
A cell is dividing by binary fission. What can you conclude? a. the cell is prokaryotic b. mitosis has taken place without cytokinesis c. the cell cycle is out of control d. homologous chromosomes have already paired e. the cyclin-CDK complex is no longer phosphorylating enzymes
A
A glucose molecule that is metabolized via aerobic respiration has been completely broken down and released as CO2 by the end of: a. the citric acid cycle b. ATP synthesis in the mitochondria c. glycolysis d. the electron transport chain e. fermentation
A
A person has a genetic disease that prevents the phospholipids in the plasma membrane of the white blood cells from freely fusing with the other membranes within the cell. How would this disease affect phagocytosis? a. the phagocytic vacuole would not fuse with the lysosome b. lysosomes would be formed lacking hydrolytic enzymes c. endocytosis would not occur d. lysosomes would not be formed e. facilitated diffusion would not occur
A
An atom X contains 14 protons, 13 electrons and 12 neutrons, and atom Y contains 14 protons, 14 electrons, and 12 neutrons. What can you conclude? a. X and Y are atoms of the same element b. X and Y are isotopes of the same element c. X and Y both have filled valance shells d. Y is an ion but X is not e. X and Y are both ions
A
An inducible operon is usually controlled by: a. an active repressor that keeps it in the "off" state b. being turned "off" usually by the end product of the pathway c. being active at all times d. an inducer molecule that keeps it in the "off" state
A
An organism that reproduces __ produces genetically variable offspring. a. sexually b. asexually c. by fragmentation d. by cloning
A
During fermentation, the immediate fate of electrons in NADH is that they: a. are transferred to an organic molecule b. are transferred to O2 c. are transferred to the electron transport chain d. are used to make CO2 e. are used to form H2)
A
During photorespiration, rubisco uses __ as a substrate. a. O2 b. glyceraldehyde-3-phosphate c. NADPH d. CO2
A
If a toxin, such as bacterial toxin, destroys ribosomes, what cellular activity will be affected first? a. protein synthesis b. energy storage c. movement d. DNA synthesis e. active transport
A
If tyrosine and isoleucine, two amino acids, undergo condensation, where does the new bond form? a. between carbon of the R group and nitrogen of the amino group b. between carbon of the carboxyl group and the hydrogen of the amino group c. between carbon of the carboxyl group and hydrogen of the R group d. between oxygen of the R group and the hydrogen of the amino group e. between carbon of the carboxyl group and the nitrogen of the amino group
A
In cells that are constantly involved in secretion, an equivalent amount of membrane must be returned to the interior of the cell for each vessicle that fuses with the plasma membrane; if this does not occur, then what would happen? a. the cell surface will keep expanding b. the cell surface would shrivel c. the ratio of cell surface would decrease, compared to cell volume d. the surface area would remain constant e. the number of membrane receptor proteins would decrease
A
In what part of a chloroplast are chlorophyll and accessory photosynthetic pigments associated? a. thylakoid membranes b. stroma c. stroma grana d. light reaction centers of the stroma
A
Is it found that a certain enzyme is synthesized whenever the solution in which the cells are growing contains substance X. This phenomenon is most likely an example of __ gene regulation. a. inducible b. repressible c. positive d. negative
A
Many intracellular receptors are transcription factors; when activated, they activate or repress specific __. a. genes b. ribosomes c. kinases d. neurons e. enzymes
A
On a scientific expedition into new territory, you discover a previously undescribed organism living within the hot environment of a geyser. The organism has a cell wall composed of pseudopeptidoglycan, is single celled, heterotropic, and has no true nucleus. In what domain would you most likely place this organism? a. archea b. bacteria c. eukarya d. not enough info to tell
A
Photosynthesis and cellular respiration are linked though the: a. calvin cycle b. the need for light c. citric acid cycle d. enzyme rubisco
A
Plants lack organ systems for disposing of toxic metabolic waste products. Their cells' vacuoles are like what animal cell organelle? a. lysosomes b. endoplasmic reticulum c. nucleolus d. mitochondria e. chloroplasts
A
RNA synthesis is also known as: a. transcription b. translation c. termination d. elongation
A
Ribulose biphosphate is synthesized from which molecule? a. G3P b. RuBP c. NADP+ d. Co2
A
The Calvin cycle is called a C3 pathway because: a. the first stable compound formed during carbon fixation is a 3-carbon compound b. the carbon atoms involved only have three bonds available (instead of the usual 4) c. 3 cyclic photophosphorylation events are necessary to "fix" one carbon dioxide d. 3 carbon dioxide molecules are needed to make one glucose molecule e. none of the above are correct
A
The energy released during the chain of electron transport molecules is used to create a(n) __ gradient across the inner mitochondrial membrane for chemiosmosis. a. proton b. oxygen c. electron d. ATP e. ADP
A
The existence of a separate set of ribosomes and __ in mitochondria and chloroplasts provide support for serial __. a. DNA; endosymbiosis b. golgi; endosymbiosis c. DNA; evolution d. rough endoplasmic reticulum; endosymbiosis e. none of the above
A
The location and/or metabolism of a substances such as a hormone or drug can be followed in the body by labeling the substance with a(n): a. radioisotope b. DNA molecule c. acid d. isotope e. element
A
The molecule that connects a growing polypeptide chain and mRNA is called: a. tRNA b. rRNA c. promoter d. RNA polymerase
A
The smooth ER is the primary site for the synthesis of phospholipids and cholesterol needed to make __. a. cell membranes b. DNA c. ATP d. ribosomes e. horomones
A
The term "fluid mosaic model" refers to the: a. movement of lipids and integral proteins within the lipid bilayer b. solubility of water in the membrane c. movement of surface proteins through the membrane d. diffusion of lipid-soluble substances through the lipid bilayer e. method of substance transport across the membrane
A
Transcriptional activation of the lac operon requires both high lactose and low glucose conditions because: a. RNA polymerase requires cAMP in order to bind to the lac operon promoter efficiently, even in the absence of the repressor b. RNA polymerase is inactive in the presence of high glucose concentrations c. high glucose concentrations stimulate cAMP activity d. glucose normally activates the lac operon repressor e. glucose and lactose compete for binding to, and inactivation of, the lac operon repressor
A
What are the reactants of the light-dependent reactions of photosynthesis? a. H20, ADP, and NADP+ b. H20, ATP, and NADPH c. CO2, ADP, and NADP+ d. CO2, ADP, and NADPH e. H20, C02, and NADP+
A
What differentiates an organic compound from an inorganic compound? a. an organic compound contains two or more carbon atoms b. an organic compound is basic rather than acidic c. an organic compound lacks valence electrons d. an organic compound lacks isotopes e. an organic compound contains two or more atoms
A
What large molecules are essential in determining the structure and function of cells and tissues? a. proteins b. RNA c. genes d. nucleotides e. horomones
A
What represents the most basic level of chemical organization? a. atom b. molecule c. tissue d. organism e. cell
A
What type of reaction is represented by a positive change in G? a. endergonic b. exergonic e. entropy d. activation e. enthalpy
A
When a small amount of HCl is added to a solution of Na2HPO4, the pH of the solution does not change markedly. The pH also does not change drastically when a small amount of sodium hydroxide (NaOH) is added to the same solution. Based on these observations, the compound Na2HPO4 is: a. acting as a buffer b. able to remove hydrogen ions from the OH- of NaOH c. acting as a solvent d. able to donate hydrogen atoms to HCl e. an enzyme facilitating the reaction between HCl and NaOH
A
When is a cell in metaphase? a. chromosomes are aligned at the midplane of the cell b. chromosomes are separated into distinct groups at opposite poles of the cell c. the nuclear envelope is clearly visible d. cytokinesis is occurring e. chromosomes are visible as threadlike structures
A
Which description illustrates the tertiary structure of a protein molecule? a. three-dimensional shape of an individual polypeptide chain b. bonding of two amino acids to form a dipeptide c. association of several polypeptide chains by weak bonds d. order in which amino acids are joined in a peptide chain e. folding of a peptide chain to form an alpha helix
A
Which of the following accurately represents the relationship between the terms anabolism, catabolism, and metabolism? a. metabolism = catabolism + anabolism b. metabolism = catabolism c. anabolism = catabolism d. anabolism = catabolism + metabolism e. catabolism = anabolism + metabolism
A
Which statement about plasma membranes is false? a. plasma membranes prevent communication with other cells b. plasma membranes transmit signals between the environment and the interior of the cel c. plasma membranes regulate the passage of materials d. plasma membranes divide the cell into compartments e. plasma membranes serve as surfaces for chemical reactions
A
Which statement best summarizes the differences between RNA and DNA? a. DNA comprises the genes, while RNA is a direct participant in the process of protein synthesis b. DNA is the primary energy currency of all cells c. DNA is a polymer and RNA is a monomer d. RNA is a single-stranded form of DNA e. RNA is a protein and DNA is a nucleic acid
A
Why can table salt (NaCl) dissolve easily in water? a. the partial positive charge of the hydrogens in the water molecule can associate with the negative charge of the chloride ion, and the partial negative charge of the oxygen of the water molecule can associate with the positive charge of the sodium atom b. water is polar and salt is nonpolar; nonpolar compounds are more soluble in polar solvents because they are able to form strong covalent bonds that result in a breaking up of the molecule being dissolved c. water can add electrons to the sodium ion d. water can form covalent linkages with salt molecules e. water can remove electrons from the chloride ion which causes the latter to dissociate from the sodium and dissolve
A
A molecule of saturated triacylglycerol contains: a. alternating single and double bonds between carbons in the fatty acid chains b. the maximum number of hydrogen bonds in the fatty acid chains c. the maximum number of triple bonds between carbons in the fatty acid chains d. fatty acid chains with both amino and carboxyl groups e. the maximum number of double bonds between carbons in the fatty acid chains
B
A patient who has a severe hemorrhage accidentally receives a large transfusion of distilled water directly into a major blood vessel. What effect will this have on the patient? a. it will have serious, perhaps fatal consequences because the red blood cells could shrink b. it will have serious, perhaps fatal consequences because the red blood cells could swell and burst c. it will have serious, perhaps fatal consequences because there would be too much fluid to pump d. it will have no unfavorable effect as long as the water is free of bacteria e. it will have no serious effect because the kidney could quickly eliminate excess water
B
A transmembrane protein differs from other membrane proteins because it: a. is a glycoprotein with carbohydrates attached b. completely extends through the membrane c. is covalently linked to the outer surface of the plasma membrane d. is attached to the inside of the membrane by an ionic bond e. is completely embedded within part of the membrane
B
All of the members of the same species occupying the same area at the same time constitute a(n): a. individual b. population c. ecosystem d. biosphere e. community
B
During non-cyclic photophosphorylation, the electrons that fill electron holes in photosystem I come from photosystem II. The electron holes now present in photosystem II are filled with electrons from: a. glucose b. water c. NADPH d. another photosystem I
B
Glycolysis yields a net energy profit of __ ATP molecules per molecule of glucose? a. four b. two c. no d. one e. six
B
If solution A is __ to B, then the direction of the net movement of water is B to A. a. hypotonic b. hypertonic c. isotonic d. gin and tonic
B
In the conversion of succinate to fumerate, hydrogen atoms are transferred to FAD formig FADH2. This is an example of: a. metabolic pathway b. redox reaction c. an aerobic reaction d. an allosteric reaction e. hydrolysis
B
In the first reaction of glycolysis, glucose receives a phosphate group from ATP. This reaction is: a. exergonic b. endergonic c. respiration d. redox reaction e. fermentation
B
Knowledge of the cell cycle has led to improved means of treating cancer. Taxol, a cancer treatment, prevents the microtubules of the spindle fiber from functioning normally. Taxol prevents the cell from entering: a. G1 b. prophase c. interphase d. G2 e. S
B
Mutations are: a. mistakes in the incorporation of amino acids in proteins b. heritable changes in the sequence of DNA bases c. heritable changes in the mRNA of an organism d. heritable changes in the sequence of DNA bases that produce an observable phenotype
B
Plasmodesmata of plant cells are functionally equivalent to the __ of animal cells that allow quick transfer of information from one cell to another: a. vesicles b. gap junctions c. tight junctions d. cell surface receptors e. anchoring junctions
B
Second messengers: a. have enzymatic activity b. can activate several other molecules within the cell c. are typically very specific in their activity d. do not amplify a signal e. all of the above
B
The __ is responsible for the separation of the chromosomes during the __ of mitosis. a. cell wall;anaphase b. mitotic spindle; anaphase c. centromere; telophase d. mitotic spindle; interphase
B
The light-independent reactions of photosynthesis involve: a. production of NADPH b. carbohydrate formation c. splitting water d. ATP formation e. all but B are part of light-independent
B
Thylakoid membranes are involved in __ synthesis. a. NADP+ b. ATP c. glucose d. G3P e. RuBP
B
To control the cell cycle: a. Cdks are active only when they are released from cyclins b. cyclins fluctuate during the cell cycle c. M-Cdk inhibits mitosis d. the activity of Cdks stays the same throughout the cell cycle
B
What type of molecules can rapidly cross a plasma membrane? a. small, hydrophillic molecules b. small hydrophobic molecules c. large, hydrophillic molecules d. small, polar molecules e. large, polar molecules
B
Where does the citric acid cycle take place in a eukaryotic cell? a. mitochondrial membrane b. mitochondrial matrix c. cytosol d. nucleus e. endoplasmic reticulum
B
Which is a benefit of sexual reproduction over asexual reproduction? a. there is less variation from generation to generation b. the interaction of the genes from both parents brings about genetic variation c. the offspring are all identical to the parents d. more offspring can be produced e. evolution will occur at a slower rate when there are two parents
B
Which list describes the correct sequence of events involved in cell signaling? a. reception, signal transmission, response, signal transduction b. signal transmission, reception, signal transduction, response c. signal transmission, signal transduction, reception, response d. signal transduction, reception, signal transmission, response e. response, signal transduction, signal transmission, reception
B
Which of the following molecules function to transfer information from one generation to the next in eukaryotes? a. tRNA b. DNA c. proteins d. mRNA
B
Which statement about lipid bilayers is false? a. they can fuse with other bilayers b. they are inflexible c. they are amphipathic d. they spontaneously form closed vesicles e. they are self-sealing
B
Why does DNA synthesis proceed in a 5' to 3' direction? a. chromosomes are aligned in the 5' to 3' direction in the nucleus b. DNA polymerases can only add nucleotides to the 3' end of a polynucleotide strand c. DNA unzips in the 5' to 3' direction d. DNA strands are parallel to each other e. the 3' end of the polynucleotide molecule contains more phosphates than the 5' end
B
You place equal numbers of dark and light varieties of feeder crickets into a terrarium containing a species of lizard. After two days you notice that the dark variety of the crickets was less common than the light variety. What process is taking place on the small scale with the terrarium? a. speciation b. natural selection c. evolution d. reproduction
B
ATP can phosphorylate many different molecules. This means that ATP can: a. convert molecules to nucleic acids b. receive phosphate groups c. donate phosphate groups d. store a large amount of energy when hydrolyzed e. all of the above
C
According to the second law of thermodynamics, the amount of usable energy available to do work in the universe __ over time. a. crashes b. increases c. decreases d. exponentially increases e. stays constant
C
After the conversion of pyruvate molecules to acetyl CoA molecules, how many NADH molecules have been produced from one glucose molecule? a. two b. one c. four d. three e. five
C
If a cell has 36 chromosomes during G1, how many molecules does it have after DNA replication? a. 108 b. 18 c. 72 d. 36
C
In glycolysis, a six-carbon glucose molecule is converted into two three-carbon molecules of a. citrate b. acetate c. pyruvate d. oxaloacetate e. coenzyme A
C
In living organisms, chemical reactions responsible for growth, repair, and nutrition are collectively referred to as: a. development b. homeostasis c. metabolism d. genetics e. adaptation
C
Isotopes differ from each other with respect to the number of: a. electrons only b. protons only c. neutrons only d. both protons and electrons e. both neutrons and protons
C
What statement best describes "biology"? a. the study of natural selection b. the naming of organisms c. the science of life d. the measurement of populations e. the study of how organisms are related to one another
C
When light intensities are adequate, the rate at which the entire process of photosynthesis occurs is primarily limited by: a. ATP concentration b. oxygen concentration c. CO2 concentration d. the amount of glucose available
C
Which of the following is an end product of glycolysis? a. NAD+ b. CO2 c. ATP d. acetyl CoA e. FADH2
C
Which of the following is false? a. cells are bombarded with numerous signals, but only respond to a few b. a cell's receptors determine whether or not the cell will respond to a signal c. there are only a few kinds of signal receptor proteins d. receptor proteins are very specific d. none of these
C
Which of the following statements about lactic acid fermentation is FALSE? a. glycolysis is the only energy-yielding step of this pathway b. it uses glucose as a substrate c. oxygen is the final electron acceptor of this pathway d. it produces two ATP molecules for every glucose molecule e. it is inefficient compared to aerobic respiration
C
Why is it advantageous for cells to be small? a. a small cell is better able to conserve energy than a larger cell b. a small cell size occupies less space in nature where space is limited c. a small cell has a small volume relative to surface area, thereby increasing efficient transport d. a small cell size prevents a cell from weighing too much e. a small cell has a small surface area relative to volume, thereby facilitating ion balance
C
A base is defined as a(n) __ acceptor. a. electron b. cation c. neutron d. proton e. anion
D
A deoxyribose nucleotide is a: a. deoxyribose plus a nitrogenous base b. nitrogenous base bonded at the 5' end to a sugar-phosphate backbone c. sugar and a phosphate d. deoxyribose plus a nitrogenous base and a phosphate
D
A sequence of three RNA bases can function as: a. a codon b. an anticodon c. a gene d. both A and B
D
Aerobic respiration is regulated by the binding of ATP or AMP to PFK to stop the production of fructose 1,6-biphosphate. This is an example of: a. an isomerase b. positive feedback c. the use of an electron carrier d. negative feedback e. none of the above
D
Cytokinesis in plant cells occurs via the formation of a: a. mitotic spindle b. Golgi complex c. cleavage furrow d. cell wall
D
Energy that is usable and organized is classified as having __. a. high entropy b. high energy c. low enthalpy d. low entropy e. low energy
D
Evidence that all living cells have a common origin is best illustrated by the: a. idea that cells are the smallest units that can carry out all life activities b. cell theory, which states that the cell is the basic unit of life c. fact that cells are the building blocks of the most complex plants d. basic similarities in cell structure and chemistry e. fact that all new cells come from previously existing cells
D
For the following medical condition, which of the following is the likely cellular organelle or structure that has been affected in such a way as to cause the condition? The sperm of a man cannot swim, thus rendering him infertile. a. chloroplast b. peroxisome c. nucleus d. mitochondria e. lysosome
D
How are hormones produced by endocrine glands typically transported to target cells? a. across a synapse b. via direct contact c. in interstital fluid d. in the blood e. through the air
D
Intermediate filaments are most closely associated with which of the following? a. myosin b. actin c. pseudopodia d. keratins e. microbilli
D
Okazaki fragments are joined together by: a. DNA polymerase b. primase c. RNA polymerase d. DNA ligase
D
The primary purpose of homeostasis is to: a. accept responses to stimuli b. convert an organism to live in a harmful environment c. allow unrestricted movement of an organism d. maintain a constant internal environment e. provide unlimited growth within an organism
D
What is the ultimate source of energy for almost all living organisms? a. carbon dioxide b. heat c. glucose d. the sun e. lipids
D
What would happen if you were to increase the temperature in an enzyme-catalyzed reaction? a. the rate of reaction will not change b. the rate of reaction will increase then level off c. the rate of reaction will decrease then level off d. the rate of reaction will increase and then decrease rapidly e. the rate of reaction will decrease and increase rapidly
D
Which functional group forms bridges to help stabilize a protein's quaternary structure? a. phosphate b. amino c. hydroxyl d. sulfhydryl e. carboxyl
D
Which of the following statements about the electron transport chain is true? a. ATP synthesis associated with the electron transport chain is an example of substrate level phosphorylation b. protons are pumped out of the mitochondria by complexes of the electron transport chain c. the movement of protons down a concentration gradient is an endergonic process d. the proton gradient established during electron transport is a form of potential energy e. the electron transport chain can be formed in the mitochondria of aerobic bacteria and other cells
D
Which statement concerning a scientific theory is FALSE? a. it is supported by many observations b. it may suggest practical applications c. it is based on a number of hypotheses d. it is unchangable
D
What is required for facilitated diffusion to take place? a. the transport of large food particles b. energy from ATP c. the transport of small nonpolar molecules d. a transmembrane protein e. movement down a concentration gradient
D & E
Accessory pigments: a. absorb only red wavelengths b. transfer energy from chlorophyll to the electron transport chain c. transfer electrons to NADP d. play no role in photosynthesis e. allow plants to absorb visible light of intermediate wavelengths
E
During cyclic photophosphorylation, electrons excited from a reaction center eventually: a. reduce phosphogylcerate b. return to the same reaction center c. are donated to NADP d. give up enough energy to produce 1 ATP molecule e. both B and D are correct
E
Gene expression in eukaryotes can be regulated: a. after translation b. during transcription and before translation c. during translation d. before transcription e. all of the above
E
Nitrogen has five electrons in its valence shell. How many electrons does it need to gain to complete its valence shell? a. one b. two c. seven d. eight e. three
E
Saturated fatty acids store more energy than unsaturated fatty acids. Based on your knowledge of aerobic respiration, you can draw this conclusion because saturated fatty acids: a. contain more ATP b. lack phosphate c. contain more ester linkages d. are deminated e. are more highly reduced
E
Signal molecules can be divided into two general classes according to their receptors. What are these two types of receptors? a. G protein-linked and protein kinase b. plasma membrane and protein kinase c. plasma membrane and ion channel d. ion channels and protein kinase e. none of the above
E
Single base changes in the coding regions of proteins can cause: a. nonsense mutations b. missense mutations c. frame-shift mutations d. silent mutations e. all of the above
E
Some enzymes have a receptor sit that is other than the active site. This is also referred to as a(n) __ site. a. sensitive b. reversible c. inhibitive d. competitive e. allosteric
E
What are the units of hereditary information? a. RNA b. nucleotides c. proteins d. hormones e. genes
E
What two organelles are both responsible for converting energy into forms that can be used by cells? a. mitochondria and peroxisomes b. lysosomes and chloroplasts c. mitochondria and lysosomes d. ribosomes and chloroplasts e. mitochondria and chloroplasts
E
What type of bond is formed if one atom is more electronegative than the other atom? a. van der Waals b. hydrogen c. covalent d. nonpolar covalent e. polar covalent
E
Which is a property of unsaturated fats? a. they have fewer fatty acids per molecule than do saturated fats b. they are more common in animals c. they have no double bonds in the carbon chains of their fatty acids d. they contain more hydrogen than do saturated fats having the same number of carbon atoms e. they are generally liquid at room temperture
E
Which of the following numbered events represents the correct sequence of events of translation initiation? 1. large ribosomal subunit binds to initiation complex 2. a tRNA carrying MET binds to the mRNA 3. small ribosomal subunit binds to the mRNA a. 2,1,3 b. 1,3,2 c. 1,2,3 d. 2,3,1 e. 3,2,1
E
Which organelle can be considered a sorting, processing, and packaging center? a. centriole b. endoplasmic reticulum c. centrosome d. vacuole e. Golgi complex
E
Which statement best describes the cell theory? a. all organisms can move from one place to another in order to find food or escape predators b. all living organisms respond to stimuli c. all living organisms grow and develop d. all living organisms can form a population of organisms that is able to adapt to the environment e. all living organisms are composed of basic units called cells
E
Which strategy is most effective for larger cells to have an effective surface area to volume ratio? a. being short and fat b. having a completely spherical shape c. locomotion d. having a thinner plasma membrane e. having thin, finger-like projections
E
__ are loosely associated with the phospholipid bilayer, whereas __ are tightly bound to it. a. glycoproteins; peripheral proteins b. integral proteins; glycoproteins c. glycolipids; glycoproteins d. integral proteins; peripheral proteins e. peripheral proteins; integral proteins
E