Biology Exam

What structural feature does glucose share with larger organic molecules, including DNA and proteins? (A) A basic structure, or backbone, formed by chains of carbon atoms (B) A ratio of 1 carbon atom to 2 hydrogen atoms to 1 oxygen atom (C) The presence of double covalent bonds between carbon atoms (D) Strong bonds between carbon atoms that cannot be broken (E) Ionic bonds between carbon atoms and oxygen atoms

(A) A basic structure, or backbone, formed by chains of carbon atoms

Which of the following activities occurs in both prokaryotic cells and eukaryotic cells? (A) Proteins are assembled on ribosomes. (B) A large central vacuole stores DNA and RNA. (C) Mitochondria provide energy for cell processes. (D) Chloroplasts capture and transform the energy of sunlight. (E) The rough endoplasmic reticulum releases enzymes to break apart wastes.

(A) Proteins are assembled on ribosomes.

The illustration to the right represents a section of DNA molecule. What characteristic of the structure of DNA allows DNA to carry coded genetic information? (A) The sequence of nitrogenous bases (B) The sequence of 5-carbon sugars (C) The quantity of phosphate groups (D) The quantity of each type of nitrogenous base (E) The pattern of 5-carbon sugars and phosphate groups

(A) The sequence of nitrogenous bases

When prokaryotic cells copy their DNA, replication begins at (A) a single point on the chromosome (B) opposite ends of the DNA molecule. (C) dozens to hundreds of points along the DNA molecule. (D) the center and proceeds out toward the ends of the DNA molecule. (E) the telomere, at the tip of the chromosome.

(A) a single point on the chromosome

Two students are developing a computer simulation of a chemical reaction that forms amino acids. Their simulation uses colored spheres to represent atoms of different elements. It uses lines connecting the spheres to represent chemical bonds. For the simulation to be accurate, which of these features should be included? (A) lines that break and reform between the spheres (B) spheres that break apart into small pieces (C) spheres that disappear during the simulated course of the reaction (D) spheres that appear during the simulated course of the reaction (E) lines that never break once they are placed

(A) lines that break and reform between the spheres

Which component of the human nervous system is correctly matched with its organizational level? (A) neuron: cell (B) nerve: organ system (C) brain: tissue (D) nervous system: organ

(A) neuron: cell

Avery and his team wanted to identify the molecule of transformation, which Griffith discovered in his experiments. They extracted a mixture of molecules from the heat-killed bacteria and treated them with enzymes that destroy specific molecules. Which of these molecules were NOT responsible for transformation, as shown by this experiment? Select all that apply. (A) proteins (B) carbohydrates (C) lipids (D) ribonucleic acid (E) deoxyribonucleic acid

(A) proteins (B) carbohydrates (C) lipids (D) ribonucleic acid

A student is developing a model that shows the steps of protein synthesis. The model should include activities in which three structures? (A) ribosomes, rough endoplasmic reticulum, Golgi apparatus (B) nucleus, Golgi apparatus, mitochondria (C) mitochondria, rough endoplasmic reticulum, nucleus (D) Golgi apparatus, nucleus, lysosome (E) nucleus, cytoskeleton, cell membrane

(A) ribosomes, rough endoplasmic reticulum, Golgi apparatus

Katie is making a model to illustrate the functions of ADP and ATP in photosynthesis. Which model best illustrates the role of ATP in photosynthesis? (A) A power plant that generates energy (B) A rechargeable battery that stores and releases energy (C) A pigment that receives the energy of sunlight (D) A pan that carries coal (E) A hammer that helps break apart water molecules

(B) A rechargeable battery that stores and releases energy

Deuterium is an isotope of hydrogen that is rare in nature. A compound nicknamed "heavy water" has identical chemical properties a normal water, but its molecules use deuterium instead of the more common hydrogen isotope. In a science experiment, Professor Byron adds heavy water to the soil of a growing plant. The plant takes up and uses heavy water in the same way it would take up normal water. After several days, the professor looks for deuterium in the plant and in the gases that the plant releases. Which is the MOST likely result of the experiment? (A) Deuterium is part of plant sugars in leaves, but no other compounds in the plant. (B) Deuterium is part of plant sugars, lipids, amino acids, and other compounds throughout the plant. (C) Deuterium is in the gases that the plant releases, but not in any plant tissues. (D) Deuterium is in the plant roots, but not elsewhere in the plant. (E) Deuterium remains in the soil, but not in any plant tissues or gases that the plant releases.

(B) Deuterium is part of plant sugars, lipids, amino acids, and other compounds throughout the plant.

What are the roles of the two test groups in this investigation? (A) Both are experimental groups, and each individually shows the effect of the direction of light. (B) One is the experimental group and one is the control group, and together they show the effect of the direction of light. (C) Both are control groups, but only Test Group 1 shows the effect of the direction of light. (D) Both are experimental groups, but only Test Group 1 shows the effect of the direction of light. (E) Both are experimental groups, but only Test Group 2 shows the effect of the direction of light.

(B) One is the experimental group and one is the control group, and together they show the effect of the direction of light.

Which of the following events may result in altered genes during eukaryotic DNA replication? (A) Hydrogen bonds between base pairs are broken (B) The enzyme telomerase is switched off (C) Duplicated chromosomes crossing-over (D) Replication proceeds in two directions (E) Replication begins in multiple places on a chromosome

(B) The enzyme telomerase is switched off

When news of a scientific discovery is reported, readers must assess the credibility of the claim. In general, which statement indicates a valid and credible claim? (A) The scientist aimed for pinpoint accuracy by using a small sample size. (B) The scientist followed strict standards of investigation and scientific methodology throughout the research. (C) The scientist assured that the experiment was broad in scope by testing many variables in each trial. (D) No other scientists replicated the experiment to avoid the legal issues of patent infringement. (E) The scientist restated the hypothesis after performing the trial in order to have a more accurate hypothesis.

(B) The scientist followed strict standards of investigation and scientific methodology throughout the research.

Which statement accurately describes the role of the light-independent reactions? (A) Transforming light energy into chemical energy (B) Transferring chemical energy to high-energy sugars (C) Returning chemical energy to light energy (D) Transferring light energy among different compounds (E) Performing chemical reactions without an energy source

(B) Transferring chemical energy to high-energy sugars

Atoms of carbon, oxygen, and hydrogen are found in all biological macromolecules. Which macromolecules are made ONLY of these three elements? (A) carbohydrates only (B) carbohydrates and lipids (C) carbohydrates, lipids, and nucleic acids (D) lipids, proteins, and nucleic acids (E) carbohydrates, proteins, and nucleic acids

(B) carbohydrates and lipids

The diagram, when labels are added, shows the reactants and energy source for photosynthesis, and one of its products. The diagram also shows interactions among the biosphere, atmosphere, and hydrosphere. Where would a label for oxygen be MOST useful to add to the diagram? (A) on the arrows pointing into the leaves (B) on the arrows pointing out of the leaves (C) on the arrows pointing into the roots (D) on a line pointing to the interior of the stem

(B) on the arrows pointing out of the leaves

Nayla is planning an investigation on the role of osmosis in maintaining homeostasis. She plans to study red blood cells in a liquid suspension, similar to blood plasma. For Nayla to observe the greatest variety of osmotic activity in the red blood cells, she should test the effect of which of these independent variables? (A) the number of red blood cells per liter of the liquid suspension (B) salt concentration of the liquid that surrounds the red blood cells (C) temperature of the liquid suspension (D) oxygen concentration of the red blood cells (E) oxygen concentration of the surrounding liquid

(B) salt concentration of the liquid that surrounds the red blood cells

A cell gains energy by combining glucose with oxygen in a series of chemical reactions. The products are carbon dioxide and water. What is the source of this energy? (A) the forces that attract protons and neutrons within carbon nuclei (B) the breaking of chemical bonds within the molecules of the reactants (C) the breaking of chemical bonds within the molecules of the products (D) the kinetic energy of oxygen molecules (E) strong forces within the atomic nuclei of the reactants

(B) the breaking of chemical bonds within the molecules of the reactants

During photosynthesis, how is the light energy that strikes the cell transformed into the chemical energy stored in sugars? (A) Energy is transferred directly to sugars, with no intermediates. (B) Energy is transferred to sugars through intermediates such as H2O, O2, and CO2 (C) Energy is transferred to sugars through intermediates, such as ATP and NADPH. (D) Energy is transferred to sugars through intermediates, such as chloroplasts. (E) Energy is transferred to sugars through light-dependent reactions.

(C) Energy is transferred to sugars through intermediates, such as ATP and NADPH.

Evolutionary theory has become the central organizing principle of biological science. Could this scientific theory ever become a scientific law? (A) Yes, if scientists decide that enough evidence supports the theory. (B) Yes, if the theory is shown to predict future events. (C) No, because a theory is a complex explanation that does not become a law. (D) No, because a theory can be proven correct while a law cannot be proven. (E) No, because a theory cannot be proven correct while a law can be proven.

(C) No, because a theory is a complex explanation that does not become a law.

Roger comparing a model of a sugar molecule to a model of an amino acid. Which of the following evidence statements would be supported by the two models? (A) Sugars and amino acids are made of exactly the same elements. (B) Sugars and amino acids have the same structure. (C) Sugars and amino acids are made of the same elements except amino acids also contain nitrogen. (D) Sugars and amino acids are made of the same elements except sugars also contain phosphorus. (E) Sugars and amino acids are both polymers.

(C) Sugars and amino acids are made of the same elements except amino acids also contain nitrogen.

In an investigation, plant cells are placed in water that has been tinted blue. The investigators observe the color of the cells changing to blue. What additional observation would be evidence that the cells maintain homeostasis in response to this change? (A) The cells burst apart. (B) The cell membranes shrinks away from the cell walls. (C) The central vacuole in the cells increases in size. (D) The cells pumps out water by endocytosis. (E) The cells pump in additional water until they burst apart.

(C) The central vacuole in the cells increases in size.

Lisa is investigating a chemical reaction involving carbon compounds. Which of these results could NOT occur, according to scientific laws about chemical reactions, matter, and energy? (A) The reaction releases energy to the environment. (B) The reaction absorbs energy from the environment. (C) The mass of carbon in the products is greater than the mass of carbon in the reactants. (D) The mass of carbon in the products is equal to the mass of carbon in the reactants. (E) The reaction occurs faster in the presence of a certain protein.

(C) The mass of carbon in the products is greater than the mass of carbon in the reactants.

In her report of an investigation, Shira states that the height of a bush is 0.65 meters. Nathaniel states that the height of the same bush is 65 centimeters. How do the statements of the two students compare? (A) Shira stated a greater height. (B) Nathaniel stated a greater height. (C) The students used different metric units to state the same height. (D) The students used different units, only one of which is metric, to state the same height. (E) Shira stated the height more accurately.

(C) The students used different metric units to state the same height.

What best describes the role of water molecules in photosynthesis? (A) Water molecules are a structural component of chloroplasts; they absorb light and pass the energy to chlorophyll. (B) Water molecules are an intermediate of photosynthesis, and are part of the electron transport chain. (C) Water molecules are an input of photosynthesis; they split apart and supply electrons to chlorophyll. (D) Water molecules are an output of photosynthesis; they are released at the end of the electron transport chain. (E) Water molecules are an intermediate of photosynthesis, and take part in the Calvin cycle.

(C) Water molecules are an input of photosynthesis; they split apart and supply electrons to chlorophyll.

In 1928 Frederick Griffith performed a series of experiments to investigate how certain types of bacteria cause pneumonia. Griffith injected mice with different types of bacteria. The table below summarizes the results of his experiments. What question was Griffith trying to answer with his experiments? (A) How do bacteria live in mice? (B) Why does heat cause bacteria to die? (C) What made the mice injected with disease-causing bacteria die? (D) What type of mice can survive when injected with bacteria? (E) How long do mice injected with bacteria live?

(C) What made the mice injected with disease-causing bacteria die?

The diagram shows the structure of valine, an amino acid. Jan is researching a procedure to synthesize valine from glucose and other compounds. The procedure involves several chemical reactions. Most likely, one of the reactions will accomplish which of these tasks? (A) removing sulfur atoms from a 6-carbon sugar (B) adding oxygen atoms to a 6-carbon sugar (C) adding an amino group (-NH2) to a carbon compound (D) removing a carboxyl group (-COOH) from a carbon compound (E) adding double bonds between two carbon atoms

(C) adding an amino group (-NH2) to a carbon compound

This model of a plant cell shows the structures that are likely to be observed in a typical plant cell. Cells from actual plants may differ from the model if the cells are specialized for specific functions. How could this model be changed to best represent a specialized leaf cell? (A) Remove the cell wall because only cells in plant stems have cell walls. (B) Remove the mitochondria because leaf cells don't need much energy. (C) Add tiny hairs because leaf cells need to take in water. (D) Add chloroplasts because leaves are where photosynthesis occurs. (E) Remove the plasma membrane because a leaf cell has a cell wall instead of a plasma membrane.

(D) Add chloroplasts because leaves are where photosynthesis occurs.

Marcus is developing a model to compare the cells of prokaryotes, such as bacteria, and the cells of multicellular eukaryotes, such as a plant or animal. He begins by drawing a model of a bacterial cell. Which strategy would be MOST useful for modeling the cells of the multicellular eukaryote? (A) Draw many cells that are the same size and shape as the bacterial cell, and in close contact with one another. (B) Draw many cells that are larger than the bacterial cell, and all the same size and shape, and in close contact with one another. (C) Draw many cells that are either larger or smaller than the bacterial cell, of a variety of sizes and shapes, and isolated from one another. (D) Draw many cells that are larger than the bacterial cell, of a variety of sizes and shapes, and in close contact with one another. (E) Draw many cells that are smaller than the bacterial cell, that lack nuclei and organelles, and in close contact with one another.

(D) Draw many cells that are larger than the bacterial cell, of a variety of sizes and shapes, and in close contact with one another.

After analyzing the results of the experiment, Valerie asks if her hypothesis should be classified as a theory. Which is the best response to Valerie's question? (A) Yes, because her data support the hypothesis. (B) Yes, but only if additional experiments show similar results. (C) No, because the experiment did not provide enough data to support the hypothesis. (D) No, because a theory is a highly reliable explanation that incorporates many well-tested hypotheses. (E) No, because a theory and a hypothesis do not relate to one another.

(D) No, because a theory is a highly reliable explanation that incorporates many well-tested hypotheses.

Plants use the sugars produced by photosynthesis to synthesize which of the following types of biomolecules? I. complex carbohydrates II. amino acids III. lipids (A) I only (B) II only (C) III only (D) I and II only (E) I, II, and III

(E) I, II, and III

Which of these statements describes how organisms could use molecules of glucose? I. Several glucose molecules could be assembled into a larger molecule. II. Glucose molecules could be broken apart to form smaller molecules. III. The atoms of glucose molecules could be combined with other elements to form a different molecule. (A) I only (B) III only (C) I and II only (D) I and III only (E) I, II, and III

(E) I, II, and III

Which of the following processes is directly controlled by the cell nucleus? (A) Osmosis because the nucleus has nuclear pores that allow water to move in and out. (B) Energy production because the nucleus contains mitochondria. (C) Cell membrane assembly because the cell membrane is made from the nuclear envelope. (D) Waste removal because a steady stream of molecules moves out of the nucleus. (E) Protein synthesis because DNA in the nucleus contains the instructions for making proteins.

(E) Protein synthesis because DNA in the nucleus contains the instructions for making proteins.

A griffin is a mythical creature that appears in many stories. It has the head of an eagle and the body of a lion. What role, if any, could the griffin have in the science of biology? (A) The griffin could be the subject of an investigation of animals. (B) The griffin could be cited as evidence to evaluate a hypothesis or theory. (C) The griffin could be used to test new ideas about animal structures or behaviors. (D) The griffin could provide data for an investigation of real animals. (E) The griffin has no role in biology, because it is not real.

(E) The griffin has no role in biology, because it is not real.

Photosynthesis converts light energy to stored chemical energy. What best describes the role of molecular oxygen (O2) in this process? (A) an essential reactant that is used to make sugars (B) an optional reactant; its presence speeds up the process (C) the main product that stores chemical energy for use by the organism (D) a byproduct that is released into the atmosphere (E) an intermediate that is neither a reactant nor product

(E) an intermediate that is neither a reactant nor product

Stewart is investigating how plants maintain homeostasis in response to the amount of water that is available to them. As part of the investigation, he studies a plant that receives sufficient water and has straight, upright stems and firm leaves. He also studies another plant that was grown in dry soil, and that has wilted stems and leaves. When Stewart examines the cells of the plants under a microscope, which organelle will display the greatest difference between the two plants? (A) the nucleus, because chromosomes thicken in water (B) the cell membrane, because water diffuses across it (C) chloroplasts, because photosynthesis depends on water volume (D) ribosomes, because protein synthesis depends on water volume (E) the central vacuole, because it stores water and provides support

(E) the central vacuole, because it stores water and provides support