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What type of reaction forms a peptide bond? (4pts) Circle the correct letter. A. Condensation reaction B.Hydrolysis C. lonic bonding What are the components of a nucleotide? A sugar, a sulfate group, and a pyrimidine A sugar, an amino acid, and a nitrogenous base A sugar, a lipid, and a nitrogenous...

What type of reaction forms a peptide bond? (4pts) Circle the correct letter. A. Condensation reaction B.Hydrolysis C. lonic bonding What are the components of a nucleotide? A sugar, a sulfate group, and a pyrimidine A sugar, an amino acid, and a nitrogenous base A sugar, a lipid, and a nitrogenous base A sugar, a phosphate group, and a nitrogenous base Match the nitrogenous bases to their group. Adenine and Guanine - purine Thymine, Cytosine, Uracil - Pyrimidine What is more stable? DNA or RNA DNA RNA What two functional groups most commonly make up carbohydrates? hydroxl amino carbonyl What does glucose most commonly exist as? linear cyclic One of the basic functions that carbohydrates perform in organisms is to serve as a ______ for more complex molecules. catalyst coordinator enzyme building block Individual monosaccharides primarily differ in the number of carbons and ____. number of hydrogen atoms number of oxygen atoms orientation of hydroxyl groups order of carbon atoms This model shows that there is more than one kind of nitrogenous base True The 3' and 5' carbon labels are in the correct locations in the model. True This model shows that there is more than one kind of sugar. False This model shows six nucleotides bonded together. False This model shows that phosphate groups bond to sugars. True This model shows that phosphate groups bond to nitrogenous bases. False This model represents two nucleic acids bonded together. False What type of change occurs to a nucleotide when it is activated? The kinetic energy of the molecule decreases The potential energy of the molecule decreases The kinetic energy of the molecule increases The potential energy of the molecule increases If ADP (two phosphates) were hydrolyzed to AMP, how would you expect this reaction to compare with the hydrolysis of ATP to AMP? More energy would be released in the hydrolysis of ADP. Less water would be used in the hydrolysis of ADP to AMP. The amount of potential energy in AMP would be lower. The change in entropy would be less in the hydrolysis of ADP. Energy in the form of heat is released. True The amount of entropy decreases when products are formed. False The reaction occurs when weak bonds are broken and stronger bonds are formed. True There is a drop in potential energy when the reactants are converted into products. True ATP is always one of the reactants. False Which of the following correctly describes nucleic acid synthesis? Polymerization of nucleic acids occurs by the formation of phosphodiester bonds. Strands in a double helix are synthesized in a parallel orientation. Complementary pairing between sugars is required for copying nucleic acids. Ribonucleotides are added to the 3' end of a DNA strand. What are the four nitrogenous bases found in RNA? adenine, cytosine, guanine, thymine (A, C, G, T) adenine, cytosine, guanine, uracil (A, C, G, U) cytosine, guanine, thymine, uracil (C, G, T, U) Single strands of nucleic acids are directional, meaning that there are two different ends. What functional groups define the two different ends of a strand? a free amino group on the 3' carbon a free hydroxyl group on the 5' carbon a free carboxyl group on the 5' carbon a free carboxyl group on the 3 carbon a free amino group on the 5' carbon a free hydroxyl group on the 3- carbon a free phosphate group on the 3' carbon a free phosphate group on the 5' carbon What are the components of a nucleotide? A sugar, an amino acid, and a nitrogenous base A sugar, a sulfate group, and a purine A sugar, a lipid, and a nitrogenous base A sugar, a sulfate group, and a pyrimidine A sugar, a phosphate group, and a nitrogenous base The condensation reaction that forms nucleic acid polymers occurs between a group on one nucleotide and a _ group on a second nucleotide. phosphate; hydroxyl carbon; carbon nitrogenous base; sugar phosphate; phosphate nitrogenous base; nitrogenous base Evaluate the possibility of hydrogen bonding between the nucleotides G-T and A-C. Explain why these pairs of bases are not complementary. In the A-C pair, only one hydrogen bond could form - between the carbonyl group of cytosine and the C-H in adenine. No hydrogen bonding would be possible in an A-C pair. In the A-C pair, two hydrogen bonds could form - between the bottom H in adenine and the carbonyl group of cytosine and between N-H groups of adenine and cytosine. In the G-T pair, only one hydrogen bond could form - between the bottom N-H in guanine and one of the carbonyl groups of thymine. In the G-T pair, two hydrogen bonds could form - between the bottom N-H in guanine and the one carbonyl group of thymine and between the carbonyl group of guanine and another carbonyl group of thymine. No hydrogen bonding would be possible in a G-T pair. If nucleotides from the DNA of a human were quantified and 30 percent of them contained the base adenine, what percentage of them would contain the base guanine? 70 percent 30 percent 40 percent 20 percent How does the structure of DNA allow it to be copied? After separating the strands of a DNA double helix, each template strand can be copied to make two identical DNA molecules. The complementary base pairs on a single strand rearrange to form two new strands that are each unique. DNA replication allows for RNA to be formed that will then code for proteins. Only one of the two DNA strands operates as a template, while the other is degraded during the process. What would be the sequence of the strand of DNA that is made from the following template: 5' - GATATCGAT - 3' (Your answer must be written 5' → 3'.) 5' ATCGATATC 3' How would this sequence be different if RNA were made from this DNA template? 5’ AUCGAUAUC 3’ In a nucleic acid polymer, the bonds that help to hold double-stranded regions together occur between what parts of the nucleotide monomers? Sugars Sugars and phosphates Nitrogenous bases and phosphates Amino acids Nitrogenous bases In a DNA double helix, what kind of chemical bonds form between the complementary nitrogenous bases? Hydrogen bonds Polar covalent bonds Phosphodiester bonds Nitrogen bonds What is primarily responsible for the functional versatility observed in RNA? Single-stranded RNA molecules will fold into different shapes based on interactions between their own bases. The sugar deoxyribose in RNA allows for versatile structures and functions. The lack of unpaired bases allows for a variety of unique structures. RNA cannot form tertiary structures, thus increasing the flexibility of the primary and secondary structures. What is responsible for the increased stability of DNA compared to RNA? DNA is a more stable molecule because it lacks a hydroxyl group on the 2' carbon. DNA is more stable because it forms phosphodiester bonds while RNA does not. DNA strands have directionality to them, while RNA strands do not. DNA is more stable since RNA has no secondary structure. According to the RNA world model, a ribozyme would replicate by creating a double-stranded RNA intermediate. Would you expect the intermediate to have the same catalytic activity as the original ribozyme? yes no Catalytic activity in ribozymes depends on the tertiary structure generated from folding single-stranded molecules. Fully double-stranded forms of the RNA would not form the same tertiary structure How do the structures of RNA and DNA differ? Adenine pairs with thymine in DNA, while adenine pairs with uracil in RNA. The sugar-phosphate backbone of DNA is formed by phosphodiester linkages, while the sugar-phosphate backbone of RNA is formed by peptide bonds. Only RNA, and not DNA, has a primary structure. Guanine pairs with cytosine in DNA, while guanine pairs with adenine in RNA. DNA contains the sugar ribose, while RNA contains the sugar deoxyribose. An RNA molecule that can catalyze chemical reactions is called a ribozyme stem-loop Tetrahymena protein What two properties would have been necessary for ribozymes to replicate in an RNA world? RNA would have to be copied to DNA and double stranded. RNA would have to have pair-to-pair bonding and consist of only four bases. RNA would require other molecules to replicate and would catalyze the production of proteins. RNA would have the production of its nucleotides catalyzed by ribozymes and they would contribute to the polymerization of RNA. What key attributes of RNA make it a candidate for the first living molecule? RNA provides a template that can be copied and can catalyze the reaction required for its own replication. RNA can replicate itself and is static without the ability to evolve. RNA provides the energy necessary for replication and consists of repeatable structural elements. RNA provides structure to cells and can be used as a molecular motor for movement. Researchers hypothesize that the first self-replicating molecule may have been DNA; RNA lipid; lipid RNA; RNA protein; protein Which of the following features was required by the first life-form, according to the chemical evolution theory? The first living molecule had to provide a template that could be copied acquire energy both provide a template that could be copied and catalyze polymerization reactions catalyze polymerization reactions maintain homeostasis Which of the following can be used to distinguish monosaccharides from one another? The number of carboxyl groups and whether they are nonpolar The number of nitrogen atoms and their polarity The number of carbon atoms they contain and the orientations of their hydroxyl groups The number of carbon atoms and whether it contains oxygen atoms Which of the differences listed here could be found among molecules of the same monosaccharide? There is a difference in the sequence of hydroxyl groups. There is a difference in the orientation of a hydroxyl group in the ring form. There is a difference in the position of the carbonyl group in the linear form. There is a difference in the number of carbons. What are three ways monosaccharides differ from one another? the number of monomers in the molecule the orientations of their hydroxyl groups the number of carbon atoms they contain the orientations of the C-1 hydroxyl the location of their carbonyl group the type of glycosidic linkage The functional group can always be found in a carbohydrate molecule. hydroxyl water amino phosphate The molecular formula of many carbohydrates is (CH2O), While hydrogen and oxygens are found in carbohydrates, water is not a functional group. A sugar that has the chemical formula CH10°g would be characterized as a polysaccharide an oligosaccharide a pentose a triose a hexose Select the structural differences that could result in different oligosaccharides consisting of two glucose residues and two galactose residues. Select the three correct statements. whether the four monomers are linked in a line or whether they form a ring whether the monomers are represented in a ring form or linear form the sequence of the monomers (e.., two galactose and then two glucose, versus alternating galactose and glucose) location of linkages (1,4 or 1,6) and types of linkages (glycosidic or phosphodiester) location of linkages (1,4 or 1,6) and types of linkages (a or B) whether the four monomers are linked in a line or whether they branch What type of bond is formed between two sugars in a disaccharide? Hydrogen bond Phosphodiester bond Peptide bond Glycosidic linkage Which two organisms use the same polysaccharide for structural support? Plants and animals Fungi and plants Bacteria and insects Fungi and insects. Plants and bacteria Which of the following polysaccharides contains peptide bonds? Chitin Starch Glycogen Peptidoglycan Glycogen consists of glucose residues consists of modified glucose residues (NAG) monomers connect by a-1,4-glycosidic linkages Chitin monomers connect by B-1,4-glycosidic linkages contains branches arising from a-1,6-glycosidic linkages- polymers interact with one another via hydrogen bonds which of the following would you have them exclude from their diet? Galactosemia is a potentially fatal disease that occurs in humans who lack the enzyme that converts galactose to glucose. If you were a physician treating a person with this disease, Maltose Lactose Mannose Starch What do egg cells contain that allow them to be recognized by sperm cells? Glycoproteins on their surface Glycoproteins in their cytoplasm Glycolipids on their surface Proteins in their cytoplasm Consider the experimental setup used by researchers to investigate the interaction between sperm and egg cells. The first steps involved isolating the surface glycoproteins from mouse eggs and then separating them into their protein and carbohydrate components. * Choose the correct terms to complete the following statement. The researchers exposed separate samples of sperm cells to the individual carbohydrate or protein components of the glycoprotein before combining sperm and eggs. What are the primary functions of carbohydrates in cells? Catalysis, digestion, energy storage, and information storage Energy storage, information storage, polymerization, and raw material source for synthesis Catalysis, energy storage, metabolism, and structure Cell identity, energy storage, raw material source for synthesis, and structure During the process of mammalian fertilization, a sperm cell encounters glycoproteins in the gelatinous extracellular matrix that surrounds the ovum. Experimental removal of sugars from these glycoproteins prevents fertilization. Which carbohydrate function is demonstrated by these results? Cell structure All of these responses are correct. Cell identity Energy storage Which of the following types of molecules would have the highest capacity to store chemical energy? A six-carbon molecule rich in C-H bonds, such as a lipid A two-carbon molecule rich in C-O bonds, such as ethanol A two carbon molecule rich in C-H bonds, such as ethane A six-carbon molecule rich in C-O bonds, such as a hexose Which of the following is a way that the various types of carbohydrates you ate during breakfast today are being used in your body right now? They catalyze reactions and control metabolic processes in the body. They code for the sequence of amino acids that make up proteins. They phosphorylate signaling molecules to control signal transduction. They are broken down to produce ATP and raw materials for building other molecules. Which of the following correctly matches the lipid with its description? Steroids have a distinctive four-ring structure with variable side groups attached. Phospholipids have three fatty acids and a phosphate-containing region. Fats consist of three fatty acids linked to a hydrophobic head. Saturated fats contain a high degree of double bonds. How do the phospholipids in archaea differ from those in other cells? They do not contain hydrocarbon chains. They have two hydrocarbon chains instead of three hydrocarbon chains. They have tails made of unsaturated fatty acids instead of saturated fatty acids. They have isoprenoid tails instead of fatty acid tails. Cooking oil lipids consist of long, unsaturated hydrocarbon chains. Would you expect these molecules to form membranes spontaneously? Why or why not? No, because energy is needed to form a membrane. Yes, because lipids always aggregate to form a membrane in water solution. Yes, because membrane phospholipids may have unsaturated hydrocarbon chains as well. No, because they have no polar end to interact with water. Describe, on a molecular level, how you would expect these lipids to behave in water. Lipids would aggregate in lipid bilayer on the surface of water. Lipids would float on the surface of the water, or collect in droplets suspended in water, reducing their interaction with water to a minimum. Lipids would dissolve in the water. They would not aggregate, reducing their interaction with water to a minimum. Lipids would aggregate in little micelles. Lipids are organic compounds characterized by their insolubility in water and their solubility in organic solvents molecular structure composed of a glycerol that is linked to a phosphate group and two hydrocarbon chains of either isoprenoids or fatty acids molecular structure composed of three fatty acids linked to a three-carbon molecule called glycerol molecular structure containing four fused rings of carbon atoms Lipids are insoluble in water because they are very large with many carbon atoms they contain nonpolar C-C and C-H bonds The statement is not true. Lipids are soluble in water. they contain multiple hydroxyl groups Which of the following is true of membrane lipids? They contain a hydrophilic head group and a hydrophobic tail. Both the head group and the tail are hydrophilic. Both the head group and the tail are hydrophobic. They contain a hydrophobic head group and a hydrophilic tail A trout moves from a warm environment into a cold environment. Predict how the saturation status of hydrocarbon chains might change to ensure proper membrane fluidity in the new cold environment.  The hydrocarbons would become less saturated to reduce the fluidity of the membrane. The hydrocarbons would become less saturated to increase the fluidity of the membrane. The hydrocarbons would become more saturated to increase the fluidity of the membrane. The hydrocarbons would become more saturated to decrease the fluidity of the membrane. A "mystery substance" was isolated in a laboratory and scientists found that the molecule readily crossed artificial membranes. Which of the following molecules can be ruled out as the "mystery substance?" СО2 H2O Chloride ion N2 O2 Decreasing the saturation of the fatty acid chains on a particular type of phospholipid would result in the formation of cholesterol glycerol more fluid bilayers a bilayer with decreased permeability to CO2 How is the chemical structure of saturated fats different from that of unsaturated fats? Saturated fats have fatty acid tails with only C = C bonds while unsaturated fats have one or more C - C bonds in the tails. Saturated fats have one long fatty acid tail with only C - C bonds while unsaturated fats have several short tails with one or more C = C bonds. Saturated fats have one long fatty acid tail while unsaturated fats have one or more short tails. Saturated fats have fatty acid tails with only C - C bonds while unsaturated fats have one or more C = C bonds in the tails. What physical property is often associated with these chemical differences? C= C bonds normally result in kinks that increase the spacing between fats and thus make unsaturated fats more fluid than saturated fats. C=C bonds normally form less hydrogen linkages which increase the spacing between fats and thus make unsaturated fats more fluid that saturated fats. C = C bonds normally result in more compact structure that decreases the spacing between fats and thus makes unsaturated fats less fluid than saturated fats. C= C bonds normally form more hydrogen linkages which decrease the spacing between fats and thus make unsaturated fats less fluid than saturated fats. Which statement describes what happens once equilibrium is reached between the interior of a vesicle and the surrounding solution? О. The direction of solute transport is the same as the direction of water transport. The transport of water and solute across the vesicle membrane ceases The transport of solute into the vesicle is equal to the transport of water out of the vesicle. There is no directional movement of solute or water across the membrane. When a vesicle containing 0.1 M Nat placed in water, the sodium ions will diffuse out and the vesicle will shrink. False When a vesicle containing 0.5 M Na+ is placed in a 0.3 M Na+ solution, water is imported and the vesicle will swell. True When a vesicle containing 0.1 M Na* is placed in a 0.1 M CI solution, water molecules will no longer move across the lipid bilayer. False When a vesicle is placed in a solution that is hypertonic to the inside, the vesicle will shrink. True What two conditions must be present for osmosis to occur? A concentration gradient and a membrane that allows water to pass but not the solute Hydrostatic pressure and a concentration gradient A concentration gradient and a membrane that allows the solute to pass but not water. Equilibrium across the membrane and hydrostatic pressure If a solution surrounding a cell is hypertonic relative to the inside of the cell, how will water move? It will not move because equilibrium exists. Water will be pumped out of the cell via active transporters. The net movement of water will be out of the cell via osmosis. The net movement of water will be into the cell via osmosis. Lipid vesicles are formed containing pure water. If these vesicles are transferred to a solution that contains a rather high concentration of solutes, the solution outside the vesicle is said to be. hypertonic hypotonic amphipathic isotonic If a solution surrounding a cell is hypotonic relative to the inside of the cell, how will water move? It will move into the cell via osmosis. It will move out of the cell via osmosis. It will evaporate from the cell surface more rapidly. It will not move, because equilibrium exists. In terms of structure, how do channel proteins differ from carrier proteins? Channel proteins are peripheral membrane proteins, while carrier proteins are integral membrane proteins. Channel proteins contribute to facilitated diffusion, while carrier proteins contribute to active transport. Channel proteins only open on one side of the membrane, while carrier proteins open on both sides of the membrane. Channel proteins form pores in the membrane, and carrier proteins undergo conformational changes to shuttle molecules across the membrane. A hypothetical cell has a higher concentration of sodium ions outside the cell than inside the cell but an equal amount of chloride outside the cell and inside the cell. Based on its electrochemical gradient, which direction would chloride ions move across the cell membrane? Chloride ions would move from inside the cell to outside down its electrochemical gradient. Chloride ions would move across the membrane in the same direction sodium ions move across the membrane. Chloride ions would move from outside the cell to the inside down its electrochemical gradient. There would be no net movement of chloride as its concentration is equal outside and inside the cell. Suppose a cell is placed in a solution with a high concentration of potassium and no sodium. How would the cellular sodium-potassium pump function in this environment? It would continue using ATP to pump sodium out of the cell and potassium into the cell. It would stop moving ions across the membrane. It would reverse the direction of sodium and potassium ions to move them against their gradients. It would move sodium and potassium ions across the membrane, but no ATP would be used. Which of the following statements regarding gated channels is false? Gated channels facilitate the passage of ions such as Cl and Na* across the plasma membrane. Gated channels allow for the passive movement of substances across the plasma membrane in a process called facilitated diffusion. Gated channels open or close in response to a signal. Gated channels facilitate the passage of small, nonpolar molecules such as O2 across the plasma membrane. The movement of molecules through a plasma membrane channel protein is always ______ down the molecule's electrochemical gradient toward the inside of the cell against the molecule's electrochemical gradient used for movement of ions paired with hydrolysis of adenosine triphosphate (ATP) If a trait shows up more in a population is must be dominant. False If I did a test cross on a blue flower and got blue and white offspring. What is the genotype of my blue flower. Blue is dominant to white BB bb Bb Do you think carbohydrates are more stable and prefer to be in their linear for or cyclic form? A. Cyclic B.Linear A simple sugar is found to have the chemical structure C6H1206. This molecule can most confidently be defined as a hexose a pentose an aldose a ketose a polysaccharide Which of these statements is NOT true? Amino acids, nucleic acids, and carbohydrates all polymerize via condensation reactions. Amino acids, nucleic acids, and carbohydrates can all form complex macromolecules. Amino acids, nucleic acids, and carbohydrates all link as only linear molecules. Amino acids, nucleic acids, and carbohydrates are found in all living organisms. Which of the following molecules contains at LEAST one peptide bond? Glycogen Cellulose Chitin Peptidoglycan