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EBIO 1210 – General Biology
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Exam 1
June 9, 2014
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1. Since the oxygen in H2O has two free electron pairs and each H has a partial positive charge, it can
be concluded that each H2O molecule in water can form a maximum of:
A) one hydrogen bond.
B) two hydrogen bonds.
C) three hydrogen bonds.
D) four hydrogen bonds.
E) five hydrogen bonds.
2. Which of the following effects is caused by the high surface tension of water?
A) Trees are able to take up water from a pond.
B) Water can act as a solvent.
C) Organisms resist temperature changes.
D) Lakes typically don’t freeze solid in winter, despite low temperatures.
E) A water strider is able to walk across the surface of a small pond.
3. Oxygen is more electronegative than sulfur. Which of the following statements is correct about the
atoms in sulfur dioxide (SO2)?
A) Each oxygen atom has a partial positive charge.
B) Each oxygen atom has a strong positive charge.
C) Each oxygen atom has a slight negative charge.
D) There are covalent bonds between the oxygen atoms.
4. Two molecules of the same substance are comprised of atoms with different electronegativities.
What type of bond will form between these two MOLECULES?
A) ionic
B) hydrogen
C) polar covalent
D) nonpolar covalent
E) no bond will form
5. Which of the properties of water listed below best explains the transport of water up a tree?
A) Water dissolves salts.
B) Water molecules form hydrogen bonds with the OH groups of tree sugars.
C) Water moderates the temperature of the tree.
D) Water molecules form hydrogen bonds between each other.
E) Water molecules do not mix with oil.
6. An example of a nonpolar covalent bond is the bond between
A) an H and an O in the same water molecule.
B) the H of one water molecule and the O of another water molecule.
C) Na+ and Cl- in salt.
D) the two hydrogen atoms in a molecule of hydrogen gas (H2).
E) Mg+and Cl- in MgCl2.
7. Hydrophilic substances such as vitamin C are
A) nonpolar substances that repel water molecules.
B) nonpolar substances that have an attraction for water molecules.
C) polar substances that have an affinity for water.
D) polar substances that repel water molecules.
8. What is the structure of a “fat” (also know as a triglyceride)?
A) a protein with tertiary structure
B) a lipid made with three fatty acids and glycerol
C) a lipid that makes up much of the plasma membrane
D) a molecule formed from three alcohols by dehydration reactions
E) a carbohydrate with three sugars joined together by glycosidic linkages
9. Estrogen and cholesterol are
A) steroids.
B) nucleic acids.
C) phospholipids.
D) carbohydrates.
E) proteins.
10. _______ involves the addition of water to _______ polymers, while _______ involves the removal
of water to ______ polymers.
A) Hydrolysis – break down – dehydration synthesis - create
B) Hydrolysis – create – dehydration synthesis – break down
C) Dehydration synthesis – create – hydrolysis – break down
D) Dehydration synthesis – break down – hydrolysis – create
11. Important dietary vitamins are:
A) Hydrophilic
B) Hydrophobic
C) Either (A) or (B)
12. How many molecules of water are needed to completely hydrolyze (break down) a polymer that is
15 monomers long?
A) 7.5
B) 8
C) 13
D) 14
13. A molecule with the chemical formula C5H10O5 is probably a
A) sugar.
B) monosaccharide.
C) lipid.
D) A and B.
E) A and C.
14. Which of the following is NOT a lipid?
A) glycogen
B) omega-6
C) testosterone
D) phospholipid
E) fat
15. Which of the following is true of chitin?
A) It is a storage polysaccharide for energy in plant cells.
B) It is a storage polysaccharide for energy in animal cells.
C) It is a major structural component of plant cell walls.
D) It is a major structural component of animal cell walls.
E) It is a major structural component of fungal cell walls.
16. How many molecules of water are produced in the construction of a fat (triglyceride)?
A) 0
B) 1
C) 2
D) 3
E) 4
17. Which of the following is false regarding unsaturated fatty acids?
A) They should be increased relative to other fats in the Western diet
B) They have double bonds between some of the carbon atoms of the fatty acids.
C) They are the principal molecules in lard and butter.
D) They are usually liquid at room temperature.
E) They are usually produced by plants.
18. What would you expect from a transport protein that allows large sugar molecules to travel across
the plasma membrane of a cell?
A) The R-groups on the amino acids facing the outer part of the cell would be hydrophobic
B) The R-groups on the amino acids facing the inside of the cell would be hydrophilic
C) The R-groups on the amino acids facing the inside of the transport channel would be hydrophilic
D) B and C only
E) A, B, and C
19. Large organic molecules are usually assembled by polymerization of a few kinds of simple
subunits. Which of the following is NOT a true polymer?
A) a polyunsaturated fat
B) cellulose
C) DNA
D) an enzyme
E) a transport protein
20. Which of the following is TRUE of both starch and glycogen?
A) They are both used for energy storage in plants
B) They are both structural components of plant cell walls
C) They are both used for energy storage in animals
D) They are both disaccharides
E) They are both polysaccharides
21. Hydrolysis reactions are used in breaking down which of the following compounds?
A) triacylglycerides
B) polysaccharides
C) proteins
D) A and C only
E) A, B, and C
22. Of the following, which best describes the sequence of steps for the synthesis and export of proteins
by components of the endomembrane system?
A) Golgi→ lysosome → ER → vesicles → cell membrane
B) rough ER → cell membrane → nuclear envelope → smooth ER
C) nuclear envelope → lysosome → Golgi → cell membrane
D) rough ER → vesicles → Golgi → vesicles → cell membrane
E) rough ER → vesicles → Golgi → vesicles → lysosome
23. Which of the following is false about lactose?
A) It is a carbohydrate
B) it is a disaccharide
C) Human tolerance of lactose depends on ethnic background
D) It is found in cow’s milk
E) None of the above
24. The molecular formula for glucose is C6H12O6. What would be the molecular formula for a
molecule made by linking three glucose molecules together by dehydration reactions?
A) C3H6O3
B) C6H10O5
C) C18H32O16
D) C18H30O15
E) C18H36O18
25. Which would likely move directly through the lipid bilayer of a plasma membrane most easily?
A) steroid hormones
B) cellulose
C) water
D) glucose
E) Na+
26. Which of the following descriptions best fits the class of molecules known as nucleotides?
A) a 5-carbon sugar and a glycerol
B) a nitrogenous base and a phosphate group
C) a nitrogenous base and a 5-carbon sugar
D) a nitrogenous base, a phosphate group, and a 5-carbon sugar
E) a phosphate group and a glycerol
27. Which of the following statements concerning unsaturated fats is true?
A) They have double bonds in the carbon chains of their fatty acids.
B) They have fewer fatty acid molecules per fat molecule
C) They contain more hydrogen than saturated fats having the same number of carbon atoms.
D) They are more common in animals than in plants.
E) They are found in butter.
28. Humans have symbiotic bacteria that help them digest cellulose.
A) True
B) False
29. Which of the following is unique to eukaryotic cells?
A) RNA.
B) a cell wall.
C) a plasma membrane.
D) lysosomes.
30. Large numbers of ribosomes are present in cells that specialize in producing which of the following
molecules?
A) proteins
B) starches
C) glucose
D) steroids
E) lipids
31. Which type of organelle would you expect to be in high concentrations in hair follicle cells, which
produce oils that nourish your hair?
A) ribosome
B) lysosome
C) smooth endoplasmic reticulum
D) mitochondrion
E) vacuole
32. Phospholipids have a _____________ head and a ____________ tail
A) hydrophilic, hydrophobic
B) hydrophobic, hydrophilic
C) hydrophilic, hydrophilic
D) hydrophobic, hydrophobic
E) cute, fuzzy
33. Tay-Sachs disease is a human genetic abnormality that results in cells accumulating and becoming
clogged with too many large, complex lipids. Scientists know these cells produce lipids at a normal
rate. Which organelle must be failing in this condition?
A) the lysosome
B) membrane-bound ribosomes
C) mitochondria
D) the Golgi apparatus
E) the endoplasmic reticulum
34. Which structure is the site of the synthesis of proteins that may be exported from the cell?
A) Golgi vesicles
B) lysosomes
C) cytoplasm
D) rough ER
E) smooth ER
35. The liver is involved in detoxification of many poisons and drugs. Which of the following
structures is primarily involved in this process and therefore abundant in liver cells?
A) rough ER
B) smooth ER
C) Transport vesicles
D) Nuclear envelope
E) Golgi apparatus
36. Which is one of the main energy transformers of cells?
A) nucleus
B) vacuole
C) lysosome
D) Golgi apparatus
E) chloroplast
37. A cell has the following molecules and structures: central vacuole, DNA, ribosomes, plasma
membrane, and a cell wall. It could be a cell from
A) any kind of organism.
B) a plant or an animal.
C) an animal, but not a plant.
D) a plant, but not an animal.
E) a bacterium.
38. The diverse functions of proteins include all of the following EXCEPT:
A) Structural support
B) Functioning as metabolic catalysts
C) Storage of energy and nitrogen
D) Transmission of genetic information to offspring
E) Movement
39. Which of the following types of molecules are the major structural components of the cell
membrane?
A) phospholipids and cellulose
B) phospholipids and proteins
C) glycoproteins and cholesterol
D) proteins and cellulose
E) nucleic acids and proteins
40. Caribou, being an arctic animal, primarily eat plants that are cold-adapted, such as Arctic willow.
Which is most likely true about the fat in a caribou’s diet? A caribou eats:
A) a high percentage of saturated fatty acids
B) a low percentage of cholesterol molecules
C) a low number of hydrophobic proteins
D) a high percentage of cholesterol molecules
E) a high percentage of unsaturated fatty acids
41. When a plant cell, such as one in a carrot, is submerged in a very hypertonic solution, what is likely
to occur?
A) the cell will burst
B) the cell membrane will lyse (break)
C) the cell will become flaccid (saggy/not full)
D) the cell will become turgid (plump/full)
E) the cell will be unchanged
42. You are a doctor in a local clinic. A patient comes to you with severe inflammation and tumors
caused by rapid cell division. While you know many issues could be contributing to this patient’s ill
health, your first questions for the patient are about his/her diet. Which of the following is the most
appropriate question for the patient?
A) Is your diet high in saturated fats?
B) Is your diet high in fiber?
C) What kind of carbohydrates do you eat most often?
D) What percentage of your diet is comprised of monounsaturated fats?
E) What kind of polyunsaturated fats do you eat most often?
43. You are an EMT and have just arrived at a serious car accident. The driver has lost a lot of blood. In
an attempt to replenish body fluids, a well-intentioned bystander hands you distilled water, saying you
should transfer this directly into one of the driver’s veins. How would you respond to this Good
Samaritan?
A) Thanks! This will work great, because the water is free of viruses and bacteria.
B) No thanks. The patient's red blood cells will burst because the blood fluid is hypertonic compared to
the cells.
C) No thanks. The patient's red blood cells will burst because the blood fluid is hypotonic
compared to the cells.
D) No thanks. The patient's red blood cells will shrivel up because the blood fluid is hypertonic
compared to the cells.
E) No thanks. The patient's red blood cells will shrivel up because the blood fluid is hypotonic
compared to the cells.
44. Which is NOT true for steroid hormones?
A) They are able to travel through the bloodstream
B) They are able to travel through the plasma membrane of a target cell
C) They are able to travel through the nuclear membrane of a target cell
D) They rely on signal transduction to deliver their message to the nucleus of the target cell
E) They are usually formed from a cholesterol-based precursor
45. In order to provide uphill transport of Na+ against its concentration gradient:
A) No energy is needed.
B) Energy is required.
C) A transport protein is needed.
D) A and C
E) B and C
46. In the process of osmosis, water molecules
A) Move from high to low concentration of water molecules (i.e. the solvent)
B) Move from high to low concentration of solute molecules
C) Osmosis does not involve water
47. Which of the following statements is correct about diffusion?
A) It requires integral proteins in the cell membrane.
B) It is very rapid over long distances.
C) It is an active process in which molecules move from a region of lower concentration to one of
higher concentration.
D) It requires an expenditure of energy by the cell.
E) It is a passive process in which molecules move from a region of higher concentration to a
region of lower concentration.
48. Hydrophilic protein hormones must use signal transduction to deliver information to cells because
they cannot easily pass through the cell membrane.
A) True
B) False
49. _____________ is the forming of vesicles from the cell membrane used to bring molecules from
outside the cell into the cell and ____________ is the merging of vesicles within the cell with the cell
membrane used to send molecules out of the cell.
A) endocytosis, exocytosis
B) exocytosis, endocytosis
C) exocytosis, signal transduction
D) signal transduction, endocytosis
50. When glucose concentration is lower in the gut than in the intestinal cells, how does glucose enter
intestinal cells from the gut?
A) through a glucose channel
B) directly through the lipid bilayer
C) via Na+-glucose cotransport fueled by the Na+/K+ pump
D) directly through the ATP-fueled Na+/K+ pump