Biology Ch. 2 & 3

Why would you expect the energy present in the bonds of glucose to be more readily available than the energy from the sugar lactose? A. Glucose is a simple sugar, and no additional processing is necessary to access the energy in the carbon-hydrogen bonds. B. Glucose has fewer double bonds than lactose, making it easier to break down. C. Lactose is a complex carbohydrate and requires a lot of breaking down before the energy can be accessed. D. It is easier to break down glucose into its component monosaccharides. E. Both glucose and lactose are simple sugars; some people, however, have difficulty breaking down lactose.

A. Glucose is a simple sugar, and no additional processing is necessary to access the energy in the carbon-hydrogen bonds.

Using the video "What are you?" (https://www.youtube.com/watch?v=JQVmkDUkZT4), what makes cancer cells so different from other conditions? A. They are like a new organism "born" within an existing organism trying to live, but essentially made up of almost all the same stuff and information as any other cell of the body. B. They can be passed from individual to individual via mosquito transference. C. They are pink and have a drooling problem. D. They are the way the body maintains the "biological social contract" by targeting invading organisms that are dangerous to the organism.

A. They are like a new organism "born" within an existing organism trying to live, but essentially made up of almost all the same stuff and information as any other cell of the body.

Ocean acidification results from __. A. absorption of carbon dioxide by chemicals in the ocean. B. acids released during the decay of dead fish and other marine organisms. C. free electrons binding to water molecules. D. free protons binding to water molecules. E. coral bleaching and the corresponding reduction of ocean calcium.

A. absorption of carbon dioxide by chemicals in the ocean.

Identify the statement below that correctly describes hydrogen bonds. A. an attraction between a slightly positive atom of one molecule and a slightly negative atom of another molecule B. attractions between hydrogen and oxygen to form a water molecule C. attractions between oppositely charged ions D. a bond between hydrogen atoms to form the molecule H2 E. any bond with a hydrogen atom

A. an attraction between a slightly positive atom of one molecule and a slightly negative atom of another molecule

Which of the following foods is not a significant source of complex carbohydrates? A. fresh fruit B. pasta C. rice D. oatmeal E. all of these are significant sources of complex carbohydrates.

A. fresh fruit

A partial sequence of a molecule is "AACTGCT." The molecule is a(n): A. nucleic acid. B. polysaccharide. C. protein. D. triglyceride. E. oligosaccharide.

A. nucleic acid.

An enzyme that can bind to and break apart molecules of lactose will: A. only be able to bind lactose. B. also be able to bind sucrose. C. also be able to bind amino acids. D. also be able to bind fatty acids. E. also be able to bind starch.

A. only be able to bind lactose.

Which of these is not considered to be a macromolecule? A. proteins B. lipids C. carbohydrates D. nucleic acids E. vitamins

E. vitamins

The secondary structure of a protein refers to the: A. twisting of the amino acid chain into a corkscrew-like shape or zigzag folding pattern. B. linear assembly of amino acids into a chain. C. configuration of the folded protein when bound to other proteins. D. three-dimensional folded structure of the protein. E. zipping of protein to fatty acid chains.

A. twisting of the amino acid chain into a corkscrew-like shape or zigzag folding pattern.

Using the video "What are you?" (https://www.youtube.com/watch?v=JQVmkDUkZT4), why is Henrietta Lacks someone you should know about? (select ALL that apply) A. Since her death in 1951, scientists and medical researchers have grown close to 50 million metric tons of her cells. B. To this day, her surviving family has not received any financial reimbursement for the use of her cells considering that a single vial of her cells goes for anywhere between $400 and $600. C. Being a woman and poor could have had something to do with the fact that her cells were taken without her permission by scientists that still use them to make many valuable discoveries. D. Even though she died a long time ago, her cells are still alive and make it more difficult to answer the question of whether or not she is actually gone.

All Correct

A carbonated soft drink that has a pH of 3 is ________ times more acidic than water. A. 1000 B. 10000 C. 3000 D. 30 E. 10

B. 10000

The atomic number of carbon is 6. The nucleus must contain __. A. 6 neutrons and 6 protons. B. 6 protons and no electrons. C. 6 protons and 6 electrons. D. 3 neutrons and 3 protons. E. 6 neutrons and no electrons.

B. 6 protons and no electrons.

The ingredient label on a container of shortening indicates "partially hydrogenated vegetable oil." This means that during processing, the number of carbon-carbon double bonds in the oil was reduced. What is the result of decreasing the number of double bonds? A. The oil now contains a higher percentage of carbohydrate. B. The oil is now more likely to be solid at room temperature. C. More "kinks" are present in the fatty acid chains, reducing the membrane density. D. The oil now has a lower melting point. E. The fatty acid is modified from a diglyceride into a triglyceride.

B. The oil is now more likely to be solid at room temperature.

Using the video "What are you?" (https://www.youtube.com/watch?v=JQVmkDUkZT4), what makes mitochondria within your cells so interesting? A. They are helper cells that aid in the function the other body cells. B. They used to be individual cells that gave up their independence so you could live. C. They are the immortal part of the cell that keeps on living after you have died. D. They are the parts of the cell responsible for protecting the cell's DNA.

B. They used to be individual cells that gave up their independence so you could live.

The O2 molecule pictured here shows two pairs of electrons shared between two oxygen atoms. This is an example of: A. weak bonding between the two atoms. B. a strong double bond. C. two unstable atoms. D. polar bonds between the two atoms. E. an ionic bond.

B. a strong double bond.

Hydrogen bonding among water molecules gives water all of the following important properties, except: A. the capacity to serve as a solvent to many other molecules. B. a transparent color. C. lower density as a solid then as a liquid. D. high heat capacity. E. strong cohesion among the individual water molecules.

B. a transparent color.

A chemical compound that releases H+ into solution is called __. A. a base. B. an acid. C. a hydrogren ion. D. a proton. E. a buffer.

B. an acid.

In terms of structural materials, _______ is to plants as _______ is to lobsters and crabs. A. a monosaccharide; a polysaccharide B. cellulose; chitin C. chitin; starch D. glycogen; cellulose E. starch; glycogen

B. cellulose; chitin

What is missing from this cell of the periodic table? A. the atomic symbol for carbon, C B. the atomic symbol for nitrogen, N C. the atomic symbol for oxygen, O2 D. the atomic symbol for oxygen, O E. the atomic symbol for nitrogen, N2

B. the atomic symbol for nitrogen, N

Water can absorb and store a large amount of heat while increasing only a few degrees in temperature. Why? A. The heat must first be used to break the covalent bonds rather than raise the temperature. B. the heat must first be used to break the hydrogen bonds rather than raise the temperature. C. An increase in temperature causes an increase in adhesion of the water. D. An increase in temperature causes an increase in cohesion of the water. E. The heat must first be used to break the ionic bonds rather than raise the temperature.

B. the heat must first be used to break the hydrogen bonds rather than raise the temperature.

One of the four nucleotide bases in DNA is replaced by a different base in RNA. Which base is it, and what is it replaced by? A. cytosine, replaced by guanine B. thymine, replaced by uracil C. uracil, replaced by guanine D. cytosine, replaced by uracil E. thymine, replaced by adenine

B. thymine, replaced by uracil

The Russian-American biochemist Phoebus Levene was the first to determine that nucleotides may contain one of four different nitrogen-containing bases. Levene believed that the nitrogen-containing bases occurred in equal amounts in DNA. What is the actual proportion of these bases? A. DNA contains equal amounts of adenine and guanine, and equal amounts of thymine and cytosine. B. DNA contains twice as much adenine and thymine as guanine and cytosine. C. DNA contains equal amounts of adenine and thymine, and equal amounts of guanine and cytosine. D. DNA contains equal amounts of guanine and thymine, and equal amounts of adenine and cytosine. E. DNA contains four times as much guanine and cytosine as adenine and thymine.

C. DNA contains equal amounts of adenine and thymine, and equal amounts of guanine and cytosine.

Using the MinuteEarth video "Where Did Earth's Water Come From?" (https://www.youtube.com/watch?v=_LpgBvEPozk) as a guide, where did the vast majority of Earth's water come from? A. Ice from the inner solar system B. Passing comets C. Deep-space, carbon-rich meteorites D. Photosynthesis

C. Deep-space, carbon-rich meteorites

Using the MinuteEarth video "Where Did Earth's Water Come From?" (https://www.youtube.com/watch?v=_LpgBvEPozk) as a guide, what were the two main forces that created the layout of the astronomical bodies (including Earth) within our solar system as we recognize it today? A. Gravity & Gas Clouds B. Solar Winds & Nuclear Fusion C. Gravity & Solar Winds D. Electrons & Solar Winds

C. Gravity & Solar Winds

A dietary fatty acid is liquid at room temperature (i.e. it has a low melting point) and contains carbon-carbon double bonds. It is most likely from __. A. a pig. B. a chicken. C. a plant. D. a cow. E. a lamb.

C. a plant.

Which of the following nucleotide bases are present in equal amounts in DNA? A. adenine & guanine B. thymine & cytosine C. adenine & thymine D. thymine & guanine E. adenine & cytosine

C. adenine & thymine

Dietary fiber is composed of: A. fatty acids. B. amino acids. C. carbohydrates. D. nucleic acids. E. proteins.

C. carbohydrates.

In an unsaturated fatty acid __. A. not all carbons in the hydrocarbon chain are bonded to hydrogen. B. no carbon-carbon double bonds are present in the hydrocarbon chain. C. carbon-carbon double bonds are present in the hydrocarbon chain. D. the hydrocarbon chain has an even number of carbons. E. the hydrocarbon chain has an odd number of carbons.

C. carbon-carbon double bonds are present in the hydrocarbon chain.

Dietary proteins: A. are considered "complete" only if they contain all of the essential amino acids required by humans. B. are nutritionally identical, because all are broken down into their constituent amino acids in the digestive system. C. consist of all 20 amino acids required in the human body. D. are considered "complete" only if they contain all of the non-essential amino acids required by humans. E. can be obtained from animal sources, but not plant sources.

C. consist of all 20 amino acids required in the human body.

Sucrose (table sugar) and lactose (the sugar found in milk) are examples of __. A. monosaccharides. B. naturally occurring enzymes. C. disaccharides. D. complex carbohydrates. E. simple sugars.

C. disaccharides.

How an atom bonds with other atoms is chiefly determined by its: A. atomic mass. B. neutrons. C. electrons. D. nuclear charge. E. protons.

C. electrons.

Using the MinuteEarth video "Where Did Earth's Water Come From?" (https://www.youtube.com/watch?v=_LpgBvEPozk) as a guide, which subatomic particle helped scientists figure out where Earth's water came from? A. quarks B. electrons C. neutrons D. protons

C. neutrons

Proteins are an essential component of a healthy diet for humans (and other animals). Their most common purpose is to serve as __. A. organic precursors for enzyme construction. B. inorganic precursors for enzyme construction. C. raw material for growth. D. fuel for running the body. E. long-term energy storage.

C. raw material for growth.

The second orbital shell of an atom can hold __ electrons. A. 3 B. 2 C. 6 D. 8 E. 4

D. 8

What can happen if an enzyme is altered, even slightly? A. It will continue to catalyze reactions, but at a slower rate. B. It will catalyze reactions too quickly, potentially causing illness for the individual. C. It will still catalyze reactions, but only at a higher temperature. D. Its active site may change, causing the enzyme to stop functioning. E. The amount of activator required to "turn on" the enzyme will need to increase.

D. Its active site may change, causing the enzyme to stop functioning.

Which statement about amino acids is false? A. They are monomers. B. They come in polar, nonpolar, and electrically charged forms. C. They are organic molecules possessing both carboxyl and amino groups. D. They are distinguished from each other by variation in their carboxyl groups. E. They combine to form proteins.

D. They are distinguished from each other by variation in their carboxyl groups.

Which statement about phospholipids is incorrect? A. They contain glycerol linking to fatty acids. B. They are a major contituent of cell membranes. C. They are hydrophilic at one end. D. They are used as organisms' chief form of short-term energy. E. They are hydrophobic at one end.

D. They are used as organisms' chief form of short-term energy.

The number of protons in an element, also called its ____________, identifies the element. A. charge B. isotope C. atomic weight D. atomic number E. nucleus

D. atomic number

Which lipid is an important component of most cell membranes? A. carboxyls B. testosterone C. glucose D. cholesterol E. estrogen

D. cholesterol

The tendency of molecules to stick together, called cohesion, is stronger in water than other liquids because the polarity of water allows a(n): A. hydrogen atom from one water molecule to form a covalent bond with the oxygen atom of another water molecule. B. hydrogen atom from one water molecule to form an ionic bond with the oxygen atom of another water molecule. C. hydrogen atom from one water molecule to form a covalent bond with the hydrogen atom of another water molecule. D. hydrogen atom from one water molecule to form a hydrogen bond with the oxygen atom of another water molecule. E. oxygen atom from one water molecule to form a hydrogen bond with the oxygen atom of another water molecule.

D. hydrogen atom from one water molecule to form a hydrogen bond with the oxygen atom of another water molecule.

Pure water and aqueous solutions that are neither acidic nor basic are said to be: A. transparent. B. buffers. C. reactive. D. neutral. E. alkaline.

D. neutral.

A covalent bond is formed when __. A. two polar molecules associate with each other in a nonpolar environment. B. one atom gives up electrons to another atom. C. two nonpolar molecules associate with each other in a polar environment. D. two atoms share electrons. E. a positively charged particle is attracted to a negatively charged particle.

D. two atoms share electrons.

Which of the following statements about enzymes is incorrect? A. Enzymes speed up chemical reactions. B. Enzymes contain an active site for binding of particular substrates. C. Enzymes are proteins. D. Enzymes can initiate chemical reactions. E. Enzymes undergo a permanent change during the reactions they promote.

E. Enzymes undergo a permanent change during the reactions they promote.

Which of the following statements about fiber is incorrect? A. The cellulose of celery stalks and lettuce leaves is fiber. B. Dietary fiber reduces the risk of colon cancer. C. Humans cannot extract energy from fiber. D. Fiber scrapes the wall of the digestive tract, stimulating mucus secretion and aiding in the digestion of other molecules. E. Fiber in the diet slows the passage of food through the intestines.

E. Fiber in the diet slows the passage of food through the intestines.

Which of the following statements about starch is incorrect? A. Starch is a polysaccharide. B. Starch is the primary form of energy storage in plants. C. Starch consists of a hundred or more glucose molecules joined together in a line. D. All of these statements about starch are correct. E. Starch tastes sweet because it is made from glucose.

E. Starch tastes sweet because it is made from glucose.

Which of the following phenomena is most likely due to the high cohesiveness of water? A. The temperature of Santa Monica Bay, off the cost of Los Angeles, fluctuates less than the air temperature throughout the year. B. All of these are due to the cohesiveness of water. C. Lakes and rivers freeze from the top down, not the bottom up. D. Adding salt to snow makes it melt. E. The fishing spider can walk across the surface of liquid water.

E. The fishing spider can walk across the surface of liquid water.

Which phenomenon is most likely due to the high specific heat capacity of water? A. Adding salt to snow makes it melt. B. Lakes and rivers freeze from the top, not the bottom. C. A lizard, called the "Jesus lizard," can run across the surface of liquid water for short distances. D. Ice cubes will float when placed in a glass of water. E. The temperature of the Santa Monica Bay, off the coast of Los Angeles, fluctuates less than the air temperature throughout the year.

E. The temperature of the Santa Monica Bay, off the coast of Los Angeles, fluctuates less than the air temperature throughout the year.

All of the following are lipids except: A. fats. B. cholesterol. C. steroids. D. triglycerides. E. insulin.

E. insulin.

All of these statements describe ways in which lipids and carbohydrates differ except: A. lipids and carbohydrates have different functions. B. lipids do not dissolve easily in water; carbohydrates do dissolve easily in water. C. lipids have more hydrogen relative to oxygen than carbohydrates have. D. lipids do not chain together to form larger molecules; carbohydrates do dissolve easily in water. E. lipids contain significantly fewer carbon-hydrogen bonds than contained in carbohydrates.

E. lipids contain significantly fewer carbon-hydrogen bonds than contained in carbohydrates.