Q&A Hero

Q: Match the following.A) DNAB) lipoproteinsC) glycoproteinsD) polysaccharideE) structural proteinsFound in hair and cartilage

Q: Match the following.A) DNAB) lipoproteinsC) glycoproteinsD) polysaccharideE) structural proteinsTransport fats throughout the body

Q: Match the following.A) DNAB) lipoproteinsC) glycoproteinsD) polysaccharideE) structural proteinsServe as cell surface receptors

Q: Match the following.A) DNAB) lipoproteinsC) glycoproteinsD) polysaccharideE) structural proteinsA carbohydrate polymer

Q: A nucleotide is a polymer of nucleic acids.

Q: All other levels of protein structure are dictated by the primary structure.

Q: Your muscles contract using contractile proteins to produce movement.

Q: Most enzymes are proteins, but not all proteins are enzymes.

Q: All hormones are steroids.

Q: Lipids with carbon-carbon double bonds tend to be more solid at room temperature.

Q: Wax is a lipid.

Q: Both men and women make testosterone.

Q: Cholesterol is used to make other steroids in the body.

Q: Glycogen is the carbohydrate found in plant cell walls.

Q: The chitin that makes up the exoskeleton of insects is a polymer of amino acids.

Q: Amino acids contain both amino and carboxyl functional groups.

Q: Hydroxyl groups are functional groups found on amino acids.

Q: Water is an organic molecule.

Q: Which of the following is the correct order for the flow of information in the cell? A) Proteins code for DNA, which codes for RNA. B) RNA codes for DNA, which codes for protein. C) DNA codes for protein, which codes for RNA. D) DNA codes for RNA, which codes for protein.

Q: Nucleotides are the building blocks for: A) disaccharides. B) ATP, DNA, and RNA. C) proteins. D) lipids. E) steroids.

Q: The two chains of nucleotides in a DNA molecule are held together by: A) covalent bonds. B) ionic bonds. C) hydrogen bonds. D) peptide bonds. E) hydrophobic interactions.

Q: Before DNA was established as the genetic material, proteins were considered the most likely molecules to serve this role. In part this belief was based on the fact that there are 20 building blocks (20 different kinds of amino acids) for proteins versus 4 building blocks (4 different nucleotides) for DNA. If proteins stored a code, there would be a far greater number of code words possible for a protein of a given number of amino acids than for a DNA molecule of the same number of nucleotides. For example, there are 16 different sequences (42) possible for a DNA two nucleotides long and 400 (202) different sequences possible for a protein two amino acids long. For a sequence three nucleotides or three amino acids in length, the number of distinct DNA sequences is ________, and the number of distinct protein sequences is ________. A) 64; 8,000 B) 800; 8,000 C) 30; 800 D) 64; 800 E) 20; 420

Q: Amino acids are monomers used to build: A) nucleic acids. B) triglycerides. C) polysaccharides. D) proteins.

Q: Alpha helices and beta pleated sheets are examples of: A) primary structure. B) secondary structure. C) tertiary structure. D) quaternary structure.

Q: Many features of a protein change when it is moved into an environment with a different pH. Which of the following features would stay the same? A) function of the protein B) shape of the protein C) binding properties of the protein D) amino acid sequence of the protein E) tertiary structure of the protein

Q: All of the following are functions of proteins except: A) hormone activity. B) enzyme activity. C) serving as structural building materials. D) serving as transport molecules. E) storing genetic information.

Q: An example of an important biological molecule that may contain the -NH2group is: A) a triglyceride. B) a starch. C) a glucose molecule. D) an enzyme. E) steroids.

Q: The difference between one amino acid and another is the: A) number of amino and carboxyl groups each contains. B) number of R groups each contains. C) type of R group each contains. D) way their amino groups bond with carboxyl groups. E) difference in the chemical properties of their amino and carboxyl groups.

Q: Proteins that are composed of more than one polypeptide chain are said to have ________ structure. A) secondary B) tertiary C) primary D) quaternary

Q: Every protein has a unique shape and function because: A) each protein has a unique sequence of nucleotides. B) each protein has a unique sequence of amino acids. C) the bonds between the amino acids vary from protein to protein. D) the number of nitrogen atoms in each amino acid differs.

Q: Saturated fats are usually found in: A) coconut oil. B) canola oil. C) safflower oil. D) a beef steak. E) both coconut oil and a beef steak.

Q: A triglyceride contains ________ fatty acid chains, whereas a phospholipid contains ________ fatty acid chains. A) two; three B) four; two C) two; four D) three; two

Q: Which of the following is a polymer? A) fat B) steroid C) nucleic acid D) wax

Q: The hydrogenation of vegetable oil results in: A) an increase in the number of double bonds between the carbon atoms. B) the oil becoming more liquid at room temperature. C) a decrease in the number of double bonds between the carbon atoms. D) the conversion of monounsaturated fatty acids into polyunsaturated fatty acids. E) a decrease in the number of hydrogen atoms in the oil molecule.

Q: Unsaturated fatty acids: A) have one or more double bonds between the carbons. B) are usually found in animal fats. C) have long been linked with heart disease. D) contain the maximum number of hydrogen atoms possible.

Q: If you removed the cuticle from the skin of an apple, the: A) apple would absorb moisture and get soggy. B) apple would lose water and dehydrate. C) seeds of the apple would die. D) apple would be inedible.

Q: Which of the following is an example of a lipid? A) cholesterol B) cellulose C) keratin D) chitin

Q: Which of the following is true of steroids? A) Steroids exist naturally in humans as hormones. B) Some amino acids are steroids. C) If people inject male steroid hormones, they can build muscle mass with no side effects. D) Steroids contain a central, single-ring carbon structure. E) Steroids are polymers.

Q: Which of the following lipids is the primary component in cell membranes? A) triglycerides B) steroids C) phospholipids D) glycerol

Q: What do wax and testosterone have in common? A) They are both hormones. B) They are both proteins. C) They are both steroids. D) They are both lipids.

Q: You notice that water is running off the feathers of a bird in the rain. The reason is probably that the bird has coated the feathers with ________, which keeps the water out of them. A) proteins B) polysaccharides C) lipids D) nucleic acids

Q: What is a triglyceride? A) a lipid made of one glycerol and two fatty acids B) a lipid made of two glycerols, a fatty acid, and a phosphate group C) a lipid made of one glycerol and three fatty acids D) a carbohydrate made of three sugars E) a polypeptide made of three amino acids

Q: Butter, which is made from milk fat, tends to be harder at room temperature than most margarines. If you wanted to make a butter that is softer at room temperature, you should consider: A) making the fatty acid chains longer. B) making fatty acid chains with fewer kinks. C) creating more double bonds in the fatty acid chains. D) saturating the fatty acid chains. E) adding more than three fatty acid chains to the triglycerides.

Q: Glycogen is used to store ________ in the ________. A) protein; muscle B) protein; liver C) nucleic acids; liver D) glucose; spleen E) glucose; liver

Q: Which of the following is the indigestible (at least for humans) glucose polysaccharide that is found in plants? A) starch B) glycogen C) cellulose D) chitin

Q: Which of the following is true of cellulose? A) Plants store glucose as cellulose. B) Animals store glucose as cellulose. C) Plants store amino acids as cellulose. D) Plants' cell walls are made up of cellulose.

Q: Chitin and cellulose are examples of: A) structural polysaccharides. B) storage polysaccharides. C) monosaccharides. D) disacchrides.

Q: Which of the following are polysaccharides? A) sucrose and glucose B) fructose and deoxyribose C) DNA and RNA D) starch and glycogen

Q: The monomers of polysaccharides are: A) nucleotides. B) simple sugars. C) amino acids. D) fatty acids.

Q: What do polysaccharides, such as cellulose; nucleic acids, such as DNA; and proteins, such as keratin, have in common? A) They are all built of chemically linked monomers. B) They are all amino acids. C) They are all lipids. D) They are all carbohydrates. E) They are all nonpolar.

Q: The monomers of polysaccharides are: A) amino acids. B) nucleotides. C) steroids. D) lipids. E) sugars.

Q: Glycogen is a polysaccharide used for energy storage by: A) plants. B) animals. C) monera. D) fungi.

Q: In the following chemical reaction, which molecule is the disaccharide? glucose + fructose → sucrose + water A) sucrose B) glucose C) water D) fructose

Q: In many cases, carbohydrates have the following ratio of elements: A) carbon, hydrogen, and oxygen in a ratio of 1:2:1. B) carbon and hydrogen in a ratio of 1:2. C) carbon, hydrogen, and nitrogen in a ratio of 1:2:1. D) carbon, oxygen, and hydrogen in a ratio of 1:2:1. E) carbon, hydrogen, and oxygen in a ratio of 2:1:2.

Q: All of the following are monosaccharides except: A) fructose. B) cellulose. C) glucose. D) deoxyribose.

Q: Which of the following contains both a carboxyl group and an amino group? A) carbohydrates B) nucleotides C) amino acids D) lipids

Q: Hydroxyl groups are commonly found in: A) amino acids. B) DNA. C) carbohydrates. D) fatty acids.

Q: Unique chemical groups that confer special properties to an organic molecule are called: A) monomers. B) amino acids. C) functional groups. D) lipids.

Q: A functional group added to a hydrocarbon usually makes the hydrocarbon: A) nonpolar. B) hydrophobic. C) polar. D) acidic. E) an isomer.

Q: Butane and isobutane are isomers. This means they have the same: A) arrangement of atoms but a different chemical formula. B) number of carbon atoms but different numbers of hydrogen atoms. C) chemical formula but a different arrangement of atoms. D) chemical formula but can only exist as ring structures.

Q: Carbon is such an important element for life because it: A) forms strong ionic bonds. B) can form chemical bonds with a maximum of four other atoms. C) can hydrogen bond to many different molecules. D) is part of the water molecule. E) does not form isomers.

Q: In some vintage science fiction movies, space travelers find themselves on a planet orbiting a distant star in which there are curious forms of life based on silicon instead of carbon. Although the story clearly is sci-fi, there is an aura of plausibility in the choice of silicon, an atom with 14 protons, in place of carbon as this alien life-form's central atom. The reason is that silicon: A) has four electrons in its outermost shell. B) has one more proton than carbon, so is very similar to it. C) is an isotope of carbon. D) is lighter than carbon. E) is heavier than carbon.

Q: Sugar is an organic molecule because it contains: A) carbon and nitrogen. B) carbon. C) water. D) carbon dioxide. E) carbon and oxygen.

Q: Refer to the figure below, and then answer the question that follows.You are working in a chemistry lab, and your lab partner knocks over a beaker of hydrochloric acid. You alert your laboratory instructor, and he immediately pours another solution over the spill to neutralize the acid. Using the figure as a guide, what did your instructor pour onto the acid to neutralize it?A) waterB) baking sodaC) lemon juiceD) coffee

Q: Refer to the figure below, and then answer the question that follows.Which of the following molecules is most likely to bind to an ion, and why?A) Molecule A, because it has electrical charges that will attract an ionB) Molecule B, because it has four hydrogen atoms on the exterior of the moleculeC) Molecule A, because any molecule with oxygen is able to bind to an ionD) Molecule B, because it has a carbon at in the center of the molecule

Q: Refer to the figure below, and then answer the question that follows. Hydrogen, deuterium, and tritium are considered the same element because:A) their mass is about the same.B) they can form ions easily.C) they have the same number of protons.

Q: You have been having trouble with acid indigestion recently. You buy some milk of magnesia, an antacid, from the drug store to relieve your indigestion. Milk of magnesia is a mixture of magnesium hydroxide in water. What makes milk of magnesia a good antacid? If you could chemically analyze your stomach fluids, what would you find before and after taking the antacid?

Q: Oil spills in the ocean are often treated with chemical dispersants. These materials are similar to detergents in that the molecules have both hydrophilic and hydrophobic portions. Based on this, predict what will happen when chemical dispersants are used to treat oil spills.

Q: Temperatures on the Earth are moderated by the presence of so much water on the planet. Using your understanding of water's temperature-moderating abilities, predict what would happen to temperatures in the tropical and temperate regions if the oceans were made of alcohol instead of water. (Hint: Water has a higher specific heat than alcohol.)

Q: How are ions formed? Why do ionic compounds readily dissolve in water?

Q: Explain how a polar molecule, such as water, can have a difference in electrical charge but is also electrically neutral.

Q: What is chemical bonding? Explain the differences between covalent and ionic bonding.

Q: What are the three most important subatomic particles in an atom called? Which one is involved in forming chemical bonds?

Q: Which elements make up the majority of the human body?

Q: A(n) ________ has a higher pH than a(n) ________.

Q: It takes more energy to raise the temperature of water than of alcohol because water has a higher ________.

Q: A signal molecule will ________ to a receptor if the molecules' shapes match, similar to a key in a lock.

Q: Hydrogen bonds may form between oxygen of one water molecule and ________ of another water molecule.

Q: Water molecules are uncharged and ________.

Q: A single covalent chemical bond represents a sharing of ________ electrons between two atoms.