Q&A Hero

Q: Respiration describes the exchange of gases between your blood and the air. Cellular respiration ________. A) produces ATP B) produces oxygen C) produces glucose D) uses carbon dioxide

Q: What compound directly provides energy for cellular work? A) C6H12O6 B) glucose C) ATP D) fat

Q: The ultimate source of the energy in food is ________. A) the sun B) producers C) ATP D) consumers

Q: Plant cells ________. A) do not need chloroplasts because their mitochondria meet their energy needs B) have chloroplasts and mitochondria C) use carbon dioxide but do not use oxygen D) do not need mitochondria because their chloroplasts meet their energy needs

Q: The waste products of cellular respiration include ________. A) water only B) carbon dioxide only C) water and carbon dioxide D) water and glucose

Q: Plants use photosynthesis to A) store chemical energy, and they use cellular respiration to harvest energy. B) change light energy into chemical energy as well as to harvest chemical energy. C) harvest energy, and they use cellular respiration to store chemical energy. D) change light energy into sugars.

Q: A horse eating some hay is an example of ________. A) an autotroph eating a producer B) an autotroph eating a consumer C) a consumer eating a producer D) a consumer eating a heterotroph

Q: Photosynthetic organisms like grass are able to ________. A) make all of their organic matter from organic molecules in the soil. B) use water they take in through their leaves as a final electron acceptor. C) change the light energy from sunlight into sugars D) use substances in the air as a major source of carbon.

Q: Photosynthetic organisms are ________. A) producers that make all of their organic matter from organic molecules that they take in B) consumers that obtain organic molecules from other living organisms C) producers that make all their own organic matter from inorganic molecules D) decomposers that obtain nutrients from the soil

Q: Humans are both ________. A) heterotrophs and consumers B) heterotrophs and producers C) producers and decomposers D) autotrophs and producers

Q: A process is referred to as aerobic if it requires ________. A) oxygen B) carbon dioxide C) ATP D) carbohydrates

Q: Lactic acid build up in muscles is a sign that ________. A) aerobic respiration capacity has not been reached B) respiration is operating effectively C) insufficient oxygen is reaching the muscles D) the muscles will be able to operate continuously for a long time

Q: The principle that energy cannot be created or destroyed is known as ________. A) cellular respiration B) conservation of energy C) conservation of heat D) entropy

Q: An object at rest has no ________ energy, but it may have ________ energy resulting from its location or structure. A) kinetic... potential B) kinetic... conserved C) potential... kinetic D) stored... potential

Q: What is energy? A) the capacity to cause movement B) the capacity to cause change C) a measure of calories D) a measure of disorder

Q: What molecules are scientists currently trying to use to power nanotechnology devices, such as microscopic robots? A) DNA B) Enzymes C) Lipids D) Cell membranes

Q: Read the following scenario to answer the following question(s). Biomedical scientists have recently developed an anticancer drug delivery system that sneaks the anticancer drug into cancer cells before releasing it. They were able to do this by using two sets of liposomes. An anticancer drug (Doxorubicin (Dox)) bound to DNA molecules was added into one set of liposomes (type A), and a high concentration of ATP molecules were added to the other set of liposomes (type B). The drug is inactive when bound to DNA molecules. Researchers inject both types of liposomes (A and B) into cancer cells, and upon doing so their contents are released. The ATP molecules (from liposome type A) bind to the DNA molecules (from liposome type B) and activate the drug, thus inducing cell death and decreasing tumor size. Mice with breast cancer tumors were treated with this liposome system to test the effectiveness of the drug. The scientists performed three trials one with both types of liposomes (Dox + ATP), one with just the drug (Dox only), and one with a salt solution (control). Examine the figure below and answer the following questions. What would be the best experiment to test the effectiveness of this anticancer drug system? A) Inject both sets of liposomes into a single healthy mouse and measure what happens to its blood ATP levels. B) Inject both sets of liposomes into a single mouse that has tumors and measure what happens to the size of the tumors. C) Inject both sets of liposomes into multiple healthy mice and measure what happens to their blood ATP levels. D) Inject both sets of liposomes into multiple mice that have tumors and measure what happens to the size of the tumors.

Q: Read the following scenario to answer the following question(s). Biomedical scientists have recently developed an anticancer drug delivery system that sneaks the anticancer drug into cancer cells before releasing it. They were able to do this by using two sets of liposomes. An anticancer drug (Doxorubicin (Dox)) bound to DNA molecules was added into one set of liposomes (type A), and a high concentration of ATP molecules were added to the other set of liposomes (type B). The drug is inactive when bound to DNA molecules. Researchers inject both types of liposomes (A and B) into cancer cells, and upon doing so their contents are released. The ATP molecules (from liposome type A) bind to the DNA molecules (from liposome type B) and activate the drug, thus inducing cell death and decreasing tumor size. Mice with breast cancer tumors were treated with this liposome system to test the effectiveness of the drug. The scientists performed three trials one with both types of liposomes (Dox + ATP), one with just the drug (Dox only), and one with a salt solution (control). Examine the figure below and answer the following questions. Why did tumor size decrease in the Dox only experiment to a lesser extent than the Dox + ATP experiment? A) ATP is actually the drug that is killing the cancer cells, not Dox. B) Dox is always active in cancer cells, so it should be able to kill some cells without ATP. C) When ATP is lacking, not as much Dox can enter the cell via facilitated diffusion. D) There is some ATP in the cancer cells normally, which acts to activate Dox.

Q: Read the following scenario to answer the following question(s). Biomedical scientists have recently developed an anticancer drug delivery system that sneaks the anticancer drug into cancer cells before releasing it. They were able to do this by using two sets of liposomes. An anticancer drug (Doxorubicin (Dox)) bound to DNA molecules was added into one set of liposomes (type A), and a high concentration of ATP molecules were added to the other set of liposomes (type B). The drug is inactive when bound to DNA molecules. Researchers inject both types of liposomes (A and B) into cancer cells, and upon doing so their contents are released. The ATP molecules (from liposome type A) bind to the DNA molecules (from liposome type B) and activate the drug, thus inducing cell death and decreasing tumor size. Mice with breast cancer tumors were treated with this liposome system to test the effectiveness of the drug. The scientists performed three trials one with both types of liposomes (Dox + ATP), one with just the drug (Dox only), and one with a salt solution (control). Examine the figure below and answer the following questions. What statement regarding this data is TRUE? A) The weight of the tumors will not change if not treated with Dox or Dox + ATP. B) Tumor weight decreases when you add Dox only to cancer cells. C) Adding Dox only or Dox + ATP result in similar decreases in tumor weight. D) Dox is entering the cancer cells via endocytosis to induce cell death.

Q: Read the following scenario to answer the following question(s). Cellular respiration converts the energy of fuel molecules to a form of energy that a cell can use to perform work. In an average day, most adult humans need to consume about 2,000 Calories to maintain their health. However, the exact amount of dietary Calories a person needs depends upon many factors, including the person's age, physical activity, size, and health. Foods that we consume vary greatly in their nutritional content and quality. A large hard-boiled egg, for example, has about 75 dietary Calories and contains about 70% of our recommended daily intake of cholesterol. Running burns approximately 600 Calories per hour. If you ate four hard-boiled eggs, how long would you have to run to burn them off? A) 10 minutes B) 30 minutes C) 60 minutes D) 120 minutes

Q: Read the following scenario to answer the following question(s). Cellular respiration converts the energy of fuel molecules to a form of energy that a cell can use to perform work. In an average day, most adult humans need to consume about 2,000 Calories to maintain their health. However, the exact amount of dietary Calories a person needs depends upon many factors, including the person's age, physical activity, size, and health. Foods that we consume vary greatly in their nutritional content and quality. A large hard-boiled egg, for example, has about 75 dietary Calories and contains about 70% of our recommended daily intake of cholesterol. The amount of dietary Calories in one hard-boiled egg could raise the temperature of ________. A) 75 grams of water by 1 degree Celsius B) 750 grams of water by 1 degree Celsius C) 1,000 grams of water by 75 degrees Celsius D) 7,500 grams of water by 50 degrees Celsius

Q: Read the following scenario to answer the following question(s). Cellular respiration converts the energy of fuel molecules to a form of energy that a cell can use to perform work. In an average day, most adult humans need to consume about 2,000 Calories to maintain their health. However, the exact amount of dietary Calories a person needs depends upon many factors, including the person's age, physical activity, size, and health. Foods that we consume vary greatly in their nutritional content and quality. A large hard-boiled egg, for example, has about 75 dietary Calories and contains about 70% of our recommended daily intake of cholesterol. If a person eats one hard-boiled egg and digests the egg fully, cellular respiration will convert most of this energy into ________. A) ATP B) heat C) carbon dioxide D) sugars

Q: Read the following scenario to answer the following question(s). Cellular respiration converts the energy of fuel molecules to a form of energy that a cell can use to perform work. In an average day, most adult humans need to consume about 2,000 Calories to maintain their health. However, the exact amount of dietary Calories a person needs depends upon many factors, including the person's age, physical activity, size, and health. Foods that we consume vary greatly in their nutritional content and quality. A large hard-boiled egg, for example, has about 75 dietary Calories and contains about 70% of our recommended daily intake of cholesterol. Molecules that come from the food we eat provide energy for the amazing work that goes on inside of our cells. This energy, stored inside of our food, is a form of ________. A) potential energy called chemical energy B) potential energy called entropy C) kinetic energy called heat D) electrical energy called heat

Q: Examine the cells below. Cells with a higher concentration of ions than the surrounding medium tend to ________. A) stay about the same size and shape B) expand C) shrink D) divide

Q: The figure below shows that ________. A) ADP can perform cellular work when it binds to an additional phosphate group B) ATP can perform cellular work when it releases a phosphate group C) ATP can be converted to ADP by adding a phosphate group D) energy is released from ATP during the process of cellular respiration

Q: Which of the following molecules spontaneously form membranes when mixed in water and most likely were one of the first organic compounds formed on Earth? A) DNA B) Enzymes C) Phospholipids D) RNA

Q: On a lab bench, there are four balloons filled with identical volumes of different salt solutions: 0% (balloon A), 5% (balloon B), 10% (balloon C), and 15% (balloon D). There are also four beakers each filled with identical volumes of a 10% salt solution. The balloons are semi-permeable; that is, only water can enter and exit the balloon. All four balloons are placed in separate beakers at the same time and are allowed to come to equilibrium. Which is the correct order of balloon volumes at equilibrium, from largest to smallest? A) A < B < C < D B) D < C < B < A C) D < B < A < C D) All balloons will be of equal volume at equilibrium.

Q: A balloon permeable to water but not to glucose contains a 10% glucose solution. A beaker contains a 5% glucose solution. What will happen when the balloon is submerged in the beaker? A) The volume of water in the beaker will decrease. B) The volume of water in the beaker will increase. C) The amount of glucose in the beaker will increase. D) The amount of glucose in the beaker will decrease.

Q: The act of a white blood cell engulfing a bacterium is ________. A) osmosis B) diffusion C) exocytosis D) phagocytosis

Q: Certain cells that line the stomach synthesize a digestive enzyme and secrete it into the stomach. Which of the following processes could be responsible for its secretion? A) endocytosis B) exocytosis C) phagocytosis D) passive transport

Q: When a person cries, tears are exported from cells through the process of ________. A) facilitated diffusion B) active transport C) endocytosis D) exocytosis

Q: Active transport ________. A) uses ATP as an energy source B) can move solutes against their concentration gradient C) can involve the transport of ions D) all of the answer options

Q: Which of the following processes could result in the net movement of a substance into a cell, if the substance is more concentrated in the cell than in the surroundings? A) active transport B) facilitated diffusion C) diffusion D) osmosis

Q: In a hypotonic solution, a plant cell will ________. A) undergo plasmolysis B) become flaccid C) burst D) become turgid

Q: If placed in tap water, an animal cell will undergo lysis, whereas a plant cell will not. What accounts for this difference? A) expulsion of water by the plant cell's central vacuole B) the relative impermeability of the plant cell membrane to water C) the relative impermeability of the plant cell wall to water D) the relative inelasticity and strength of the plant cell wall

Q: Some protozoans have special organelles called contractile vacuoles that continually eliminate excess water from the cell. The presence of these organelles tells you that the environment ________. A) is isotonic to the protozoan B) is hypotonic to the protozoan C) is hypertonic to the protozoan D) contains a higher concentration of solutes than the protozoan

Q: A cell that neither gains nor loses a net amount of water at equilibrium when it is immersed in a solution is ________. A) isotonic to its environment B) hypertonic to its environment C) hypotonic to its environment D) metabolically inactive

Q: When two solutions that differ in solute concentration are placed on either side of a selectively permeable membrane, and osmosis is allowed to take place, the water will ________. A) exhibit a net movement to the side with lower water concentration B) exhibit a net movement to the side with higher water concentration C) exhibit a net movement to the side with lower solute concentration D) exhibit an equal movement in both directions across the membrane

Q: A balloon permeable to water but not to glucose contains a 10% glucose solution. A beaker contains a 5% glucose solution. Which of the following is TRUE? A) The solution in the beaker is hypertonic relative to the solution in the balloon. B) The solution in the balloon is isotonic; the solution in the beaker is hypertonic. C) The solution in the balloon is hypotonic relative to the solution in the beaker. D) The solution in the balloon is hypertonic relative to the solution in the beaker.

Q: Osmosis can be defined as ________. A) the diffusion of water across a selectively permeable membrane B) the diffusion of nonpolar molecules across a selectively permeable membrane C) active transport across a selectively permeable membrane D) the diffusion of a solute across a selectively permeable membrane

Q: Facilitated diffusion across a biological membrane requires ________ and moves a substance ________ its concentration gradient. A) energy... down B) transport proteins... down C) energy and transport proteins... against D) transport proteins... against

Q: Diffusion ________. A) is the result of the potential energy of atoms B) requires an input of cellular energy C) occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated D) proceeds until equilibrium is reached

Q: Diffusion is an example of ________. A) phagocytosis B) active transport C) endocytosis D) passive transport

Q: Which one of the following is most similar to the mechanism of an enzyme inhibitor? A) keeping someone from parking by parking in their designated spot B) driving the wrong way on a one-way street C) forgetting to put a cap back on a pen D) changing the tires on a car

Q: Substances that plug up an enzyme's active site are ________. A) enzyme substrates B) enzyme inhibitors C) enzyme catalysts D) enzyme products

Q: Which one of the following is TRUE? A) An enzyme's function depends on its three-dimensional shape. B) Enzymes work generally on a broad range of substrates. C) Enzymes are used up in chemical reactions. D) Enzymes emerge changed from the reactions they catalyze.

Q: Which component of the following reaction is the substrate?sucrose + sucrase + water -> sucrase + glucose + fructoseA) sucroseB) sucraseC) glucoseD) fructose

Q: The region of an enzyme to which a substrate binds is called the ________ site. A) active B) substrate C) enzymatic D) inactive

Q: Which component of the following reaction is the enzyme?sucrose + sucrase + water -> sucrase + glucose + fructoseA) sucroseB) sucraseC) glucoseD) fructose

Q: An enzyme's function is most dependent on its ________. A) pH B) temperature C) shape D) size

Q: Which one of the following is TRUE? A) Enzymes are the products in a chemical reaction. B) Enzymes are the reactants in a chemical reaction. C) Enzymes catalyze specific reactions. D) Enzymes' functions require inhibitors.

Q: Enzymes increase the rate of a reaction by ________. A) increasing the temperature of the substrates B) contributing electrons to the reaction C) decreasing activation energy D) changing the pH of the environment

Q: The sum total of all the chemical reactions that occur in organisms is called ________. A) hydrolysis B) cellular synthesis C) conservation of energy D) metabolism

Q: Usually, enzymes are ________. A) fats B) steroids C) chemical reactions D) proteins

Q: Anything that prevents ATP formation will most likely ________. A) result in cell death B) force the cell to rely on lipids for energy C) force the cell to rely on ADP for energy D) have no effect on the cell

Q: Energy is transferred from ATP to other molecules by transferring a(n) ________. A) adenosine B) heat unit C) ADP D) phosphate group

Q: What compound directly provides energy for cellular work? A) sugar B) ATP C) DNA D) fat

Q: You have a 2-kg bottle of liquid water at 0C. About how many Calories are needed to heat up the water to 100C? A) 100 Calories B) 200 Calories C) 2,000 Calories D) 10,000 Calories

Q: Ten kilocalories are equivalent to ________ calories. A) 1,000 B) 10,000 C) 0.1 D) 100

Q: Humans convert approximately ________ of the energy stored in food to useful work. A) 22% B) 34% C) 55% D) 99.9%

Q: Glucose molecules provide energy to power the swimming motion of sperm. In this example, the sperm are changing ________. A) chemical energy into kinetic energy B) chemical energy into potential energy C) kinetic energy into potential energy D) kinetic energy into chemical energy

Q: Which of the following is a measure of randomness in a system? A) entropy B) kinetic energy C) potential energy D) chemical energy

Q: You are riding on your bike and stop pedaling, coasting along the road. Eventually, your bike slows down and stops. What happened to the energy of your motion when your bike stopped? A) It was returned to the bicycle. B) It was converted back to chemical energy. C) It was released as heat. D) It was used to chemically break down the tires.

Q: A rock on the top of a mountain contains ________ energy. A) potential B) no C) kinetic D) conserved

Q: Read the following scenario to answer the following questions. Different species of bacteria are resistant to different types of antibiotics. For example, one species of bacteria may be resistant to an antibiotic that targets bacterial ribosomes but may not be resistant to a different antibiotic that targets bacterial cell walls. In order to figure out what type of antibiotic(s) to which a species of bacteria was resistant, a researcher treated the bacteria with four different antibiotics (A, B, C, and D) and measured how many bacteria were alive over the course of a few weeks. The data that she collected are summarized below. If you were treating a patient infected with this species of bacteria, which antibiotic would you prescribe the person such that the bacteria were killed most effectively? A) Antibiotic A B) Antibiotic B C) Antibiotic C D) Antibiotic D

Q: Read the following scenario to answer the following questions. Different species of bacteria are resistant to different types of antibiotics. For example, one species of bacteria may be resistant to an antibiotic that targets bacterial ribosomes but may not be resistant to a different antibiotic that targets bacterial cell walls. In order to figure out what type of antibiotic(s) to which a species of bacteria was resistant, a researcher treated the bacteria with four different antibiotics (A, B, C, and D) and measured how many bacteria were alive over the course of a few weeks. The data that she collected are summarized below. Why do you think the bacteria start to decline when treated with antibiotic C but then begin to grow as time goes on? A) Some bacteria with resistance to antibiotic C were selected for over time. B) Additional bacteria were added to the experimental group. C) Antibiotic C degraded and thus was no longer effective. D) This is the normal course of bacterial growth no matter which antibiotic is applied.

Q: Read the following scenario to answer the following questions. Different species of bacteria are resistant to different types of antibiotics. For example, one species of bacteria may be resistant to an antibiotic that targets bacterial ribosomes but may not be resistant to a different antibiotic that targets bacterial cell walls. In order to figure out what type of antibiotic(s) to which a species of bacteria was resistant, a researcher treated the bacteria with four different antibiotics (A, B, C, and D) and measured how many bacteria were alive over the course of a few weeks. The data that she collected are summarized below. The bacteria show the greatest resistance to which antibiotic? A) Antibiotic A B) Antibiotic B C) Antibiotic C D) Antibiotic D

Q: Read the following scenario to answer the following questions. The earliest cells detectable in fossils were different from the cells in animals, plants, fungi, and protists living today. These first prokaryotic cells gave rise to eukaryotic cells approximately 1.7 billion years ago. The structure of eukaryotic cells today suggests how they might have evolved from their prokaryotic ancestors. Scientists examining mitochondria and chloroplasts now think that these organelles were probably free-living prokaryotes before becoming a part of eukaryotic cells long ago. Which of the following is a characteristic of mitochondria that suggests that they might have evolved from free-living bacteria? A) Mitochondria have cell walls. B) The plasma membrane of a mitochondrion, forming the surface of this organelle, is the site of many important steps of cellular respiration. C) Mitochondria have their own DNA. D) Mitochondria rely upon proteins as their source of energy.

Q: Read the following scenario to answer the following questions. The earliest cells detectable in fossils were different from the cells in animals, plants, fungi, and protists living today. These first prokaryotic cells gave rise to eukaryotic cells approximately 1.7 billion years ago. The structure of eukaryotic cells today suggests how they might have evolved from their prokaryotic ancestors. Scientists examining mitochondria and chloroplasts now think that these organelles were probably free-living prokaryotes before becoming a part of eukaryotic cells long ago. Which of the following is a characteristic of chloroplasts that suggests that they might have evolved from free-living bacteria? A) Chloroplasts have cell walls. B) Chloroplasts contain pigments. C) Chloroplasts have their own DNA. D) A single, highly folded plasma membrane surrounds chloroplasts.

Q: Read the following scenario to answer the following questions. The earliest cells detectable in fossils were different from the cells in animals, plants, fungi, and protists living today. These first prokaryotic cells gave rise to eukaryotic cells approximately 1.7 billion years ago. The structure of eukaryotic cells today suggests how they might have evolved from their prokaryotic ancestors. Scientists examining mitochondria and chloroplasts now think that these organelles were probably free-living prokaryotes before becoming a part of eukaryotic cells long ago. What evidence suggests that mitochondria might have evolved before chloroplasts? A) Mitochondria can sometimes divide to produce chloroplasts. B) Only mitochondria have their own DNA. C) Some mitochondria have chloroplasts inside of them. D) Almost all eukaryotes have mitochondria but only some cells have chloroplasts.

Q: The child shown in the figure below is not feeling well. Why does the poster say "No Antibiotics Please"? A) His illness may be caused by an allergy to penicillin. B) Antibiotics should be taken only to promote growth. C) His illness is caused by bacteria. D) His illness is caused by a virus.

Q: The figure below shows a Paramecium, a single-celled freshwater protist. The hairlike structures visible on the Paramecium allow it to move. These structures are ________. A) microfilaments B) intermediate filaments C) flagella D) cilia

Q: Examine the structures of the plant and animal cells below. Which of the following organelles connect(s) to the nuclear envelope? A) the Golgi apparatus B) lysosomes C) mitochondria D) the endoplasmic reticulum

Q: Using the figure below for a reference, approximately how many times larger is a nucleus compared to a protein? A) 10 times larger B) 100 times larger C) 1,000 times larger D) 10,000 times larger

Q: Tobacco smokers (and those exposed to tobacco smoke) are at greater risk of an ectopic (tubal) pregnancy. Based on your understanding of the structures of the cytoskeleton, what is the BEST explanation? A) Tobacco interferes with the microtubule network of eggs thus weakening their structure. B) Tobacco interferes with the functioning of the flagella propelling sperm. C) Tobacco interferes with microfilament formation in sperm, thereby forcing the zygote to implant in a fallopian tube. D) Tobacco interferes with the sweeping motion of cilia that aids in the movement of the egg toward the uterus.

Q: Microtubules are associated with ________. A) cilia B) flagella C) cell shape D) all of the answer choices

Q: Which of the following is an adaptation to increase the surface area of a part of a cell that is involved in cellular respiration? A) the cristae of a mitochondrion B) the outer membrane of a chloroplast C) the grana of a chloroplast D) the endoplasmic reticulum

Q: Cellular respiration can be described as the conversion of the energy ________. A) of sunlight to energy stored in organic compounds B) stored in food molecules to energy stored in ATP C) stored in ATP to energy stored in food molecules D) stored in ATP to energy used to do work

Q: Which plant organelle is responsible for photosynthesis? A) smooth endoplasmic reticulum B) mitochondrion C) ribosome D) chloroplast

Q: Similar to the nucleus, chloroplasts and mitochondria are ________. A) surrounded by two membranes B) able to synthesize carbohydrates C) manufactured by the nucleolus D) able to synthesize lipids