General Biology (Bio 11A) Spring 2012
Name
Exam 1
MULTIPLE CHOICE. Select the ONE choice that BEST answers the question. Write your answer in the
space provided. (2 points each)
____ 1. Which series of terms is in the sequence of biological organization from the simplest to the most
complex?
A. organ, tissue, population, ecosystem
B. organism, ecosystem, community, population
C. cell, tissue, organ, population
D. tissue, cell, membrane, molecule
E. community, population, ecosystem, habitat
____ 2. Plants obtain the energy for photosynthesis from _______.
A. the soil
B. chemicals
C. light
D. oxygen
E. carbon dioxide
____ 3. Single-celled amoebas and bacteria are grouped into different domains because _______.
A. amoebas eat bacteria
B. bacteria are not made of cells
C. bacterial cells lack a membrane-bound nucleus
D. amoebas are motile, bacteria are not
E. bacteria decompose amoebas
____ 4. Researchers testing new drugs usually give the drug to one group of people and give sugar pills,
called placebos, to the other group. The group receiving the drug ________.
A. is the control group
B. is the experimental group
C. is needed for repeated testing
D. is a back up in case people getting the placebo drop out
E. is the experimental variable
____ 5. Which of the following statements best distinguishes hypotheses from theories in science?
A. Theories are hypotheses that have been proven.
B. Hypotheses are tentative guesses; theories are correct answers to questions about nature.
C. Hypotheses are theories are different terms for the same thing in science
D Hypotheses are usually narrow in scope; theories have broad explanatory power.
____ 6. Pelicans are members of the _______.
A. Domain Bacteria B. Domain Archaea
E. Domain Eukarya
C. Kingdom Protista
D. Kingdom Plantae
____ 7. Evolution by natural selection relies upon
A. overproduction of offspring
B. a struggle for existence C. heritable variation
D. individual variation
E. all of the choices are correct
____ 8. A positive ion is formed when an atom
A. loses a neutron
B. becomes part of a molecule
D. loses an electron
E. is split by nuclear fission
C. gains an electron
____ 9. A sulfur atom has 6 electrons in its outer shell. As a result, it forms ____ covalent bonds with other
atoms.
A. two
B. three
C. four
D. six
E. eight
____ 10. A substance that cannot be broken down into other substances by ordinary chemical means is
A. a buffer
B. a compound
C. a molecule
D. an element
E. a cell
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____ 11. A solution at pH 6 contains ______ than the same amount of a solution at pH 8.
A. 2 times more H+
B. 4 times more H+
C. 4 times less H+ D. 100 times more H+
+
F.
E. 100 times less H
____ 12. The formation of larger polymers from smaller subunit molecules is known as a ____ reaction?
A. reduction
B. oxidation C. phosphorylation D. dehydration synthesis
E. hydrolysis
____ 13. Covalent bonds can occur where atoms share one or more pairs of electrons. Which of the
following would form a double covalent bond?
A. NH3
B. NaCl
C. Cl2
D. CO2
E. none of the choices are correct
____ 14. Sulfur and nitrous oxides released into the atmosphere eventually result in acid precipitation.
These compounds result from ____.
A. burning of fossil fuels
B. the destruction of rain forests
C. the breakdown of ozone
D. overfishing
____ 15. A nucleotide is made of _____ .
A. sugar, water, and phosphate
C. a base, sugar, and phosphate
E. water, sugar, and a base
B. starch, base, and phosphate
D. phosphate, water, and a base
____ 16. What does the term amino acid signify about the structure of the molecule?
A. It consists of an amino group only
B. It consists of an amino group and a carbonyl group
C. It consists of an amino group and a carboxyl group
D. It consists of a carboxyl group only
____ 17. Which element is most particularly associated with organic chemistry?
A. sulfur
B. carbon
C. nitrogen
D. potassium
E. oxygen
____ 18. The term for compounds that do not mix well with water is ___________.
A. monomeric.
B. hydrophobic.
C. polar.
D. hydrophilic.
E. hydrolized.
____ 19. Which of the following is the process in which a phosphate group attaches to another molecule?
A. dehydration B. hydrolysis C. phosphorylation D. reduction
E. oxidation
____ 20. Unsaturated fats ________.
A. are more common in animals than in plants B. have fewer fatty acid molecules per fat molecule
C. are associated with greater health risks than saturated fats
D. are usually solid at room temperature
E. have double bonds in their fatty acid chains
____ 21. Enzymes require a specific shape to function. Which of the following might alter the protein shape?
A. heating
B. changing salt concentration
C. changing the pH
D. denaturation
E. all of the choices are correct
____ 22. What do limits on maximum cell size depend on?
A. the number of organelles B. surface-to-volume ratio C. number of surrounding cells
D. amount of DNA in the nucleus
E. thickness of the cell membrane
____ 23. Which of the following might be called the cell's “command center” organelle?
A. lysosome
B. mitochondrion
C. vesicle
D. chloroplast
E. nucleus
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____ 24. What changes would you expect to see in the liver cells of someone suffering from chronic
alcoholism?
A. Increased levels of endoplasmic activity B. decreased levels of nuclear permeability
C. increase levels of mitochondrial activity D. decreased levels of DNA synthesis
____ 25. In which cell would you expect to find the most lysosomes?
A. muscle cell in thigh of long-distance runner
B. pancreatic cell that secretes enzymes
C. ovarian cell that produces the steroid estrogen D. cell in tissue layer lining digestive tract
E. white blood cell that engulfs bacteria
____ 26. This organelle contains an inner membrane that is highly folded and performs cellular respiration.
A. ribosomes B. nucleus C. mitochondria D. chloroplasts E. both A and D are correct
____ 27. Which of the following would NOT be found in a cellʼs cytoplasm?
A. a ribosome
B. fluid in which organelles are found
C. mitochondria
D. a vesicle E. the nucleus
____ 28. Membrane proteins are synthesized by ribosomes that can be attached to ____.
A. the Golgi apparatus
B. lysosomes
C. the nucleolus
D. mitochondria
E. the endoplasmic reticulum
____ 29. Photosynthesis is an example of _____.
A. an exergonic reaction
B. an endergonic reaction
D. thermodynamics
E. entropy
C. bioenergetics
____ 30. Which best describes the structure of a cell membrane?
A. phospholipids between two layers of protein
B. proteins between two layers of phospholi[ids
C. proteins embedded in two layers of phopholipids
D. cholesterol embedded in two layers of phospholipids
E. a layer of protein coating a layer of phospholipids
____ 31. Which of the following does not diffuse across the lipid bilayer of cell membranes?
A. water molecules B. oxygen gas C. hydrogen ions D. carbon dioxide
E. all are correct
____ 32. The movement of atoms, ions, or molecules from a region of lower concentration to regions of
higher concentration is called ___.
A. spontaneous combustion
B. active transport C. heat D. crenation E. diffusion
____ 33. The method of transport across a membrane that requires a transport protein and energy, is
A. simple diffusion
B. active transport
C. facilitated diffusion
D. osmosis
E. endocytosis
____ 34. The diffusion of water across a selectively permeable membrane is called ____.
A. exocytosis
B. osmosis
C. facilitated diffusion
D. passive transport
E. active transport
____ 35. Which one of the following is NOT needed for facilitated transport?
A. a concentration gradient
B. a membrane
D. an outside energy source
E. none of the choices are correct
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C. a solute molecule
TRUE/FALSE. Write T for TRUE, and F for FALSE, in the space provided. (2 points each)
____ 36. The diversity of life can be arranged into three Domains; Bacteria, Archaea and Eukarya.
____ 37. Natural selection is the mechanism that explains how evolution happens.
____ 38. N-16, a radioactive form of nitrogen, has a different # of neutrons than other nitrogen atoms.
____ 39. Each unit change in the pH scale represents a five-fold change.
____ 40. If the atoms in a molecule share electrons equally, the molecule is said to be nonpolar.
____ 41. Cows can derive nutrients from cellulose because they have bacteria that can break it down.
____ 42. In hydrolysis reactions, water is released as a product of the reaction.
____ 43. You could expect a muscle cell in a long-distance runner to have lots of smooth ER.
____ 44. The purpose of cellular respiration is the production of ATP energy used by the cell.
____ 45. The endoplasmic reticulum is a biosynthetic factory.
____ 46. A single specific enzyme can catalyze a wide variety of different chemical reactions.
____ 47. Diffusion is the spontaneous movement of particles “down” their concentration gradient.
SHORT ANSWER. Answer the questions in the space provided. (3 points each)
1. How are ionic bonds and covalent bonds different? Give a specific example for each.
2. Explain how a protein inside the ER can be exported from the cell without ever crossing a
membrane. Use a drawing to show the process.
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