front 1 Which of these is not transported via the symplasm? | back 1 DNA |
front 2 The ancestors of land plants were aquatic algae. Which of the following is not an evolutionary adaptation to life on land? | back 2 C3 photosynthesis |
front 3 Which of the following is a correct statement about sugar movement in phloem? | back 3 Movement can occur both upward and downward in the plant |
front 4 Ignoring all other factors, what kind of day would result in the fastest delivery of water and minerals to the leaves of a tree? | back 4 warm, dry day |
front 5 Arrange the following five events in an order that explains mass flow of materials in the phloem 1. water diffuses into the sieve tubes 2. leaf cells produce sugar by photosynthesis 3. solutes are actively transported into sieve tubes 4. sugar is transported from cell to cell in the leaf 5. sugar moves down the stem | back 5 2, 4, 3, 1, 5 |
front 6 Assume that a particular chemical interferes with the establishment and maintenance of proton gradients across the membranes of plant cells. All of the following process would be directly affected by this chemical except | back 6 xylem transport |
front 7 In plant roots, the Casparian strip is correctly described by which of the following? | back 7 it ensures that all the water and dissolved substances must pass through a cell membrane before entering the stele |
front 8 What is the main cause of guttation in plants? | back 8 root pressure |
front 9 Most angiosperms have alternate phyllotaxy. What allows each leaf to get the maximum exposure to light and reduces shading of lower leaves? | back 9 leaf emergence as an angle of 137.5 from the site of previous leaves |
front 10 Plants do not have a circulatory system like that of some animals. If a given water molecule did circulate (go from one point in a plant to another and back), it would require the activity of | back 10 both the xylem and phloem |
front 11 Phloem transport is described as being from the source to the sink. Which of the following would most accurately complete this statement about phloem transport as applied to most plants in the late spring? Phloem transports ___ from the ___ source to the ___ sink. | back 11 sugars; leaf; apical meristem |
front 12 Which structure or compartment is not part of the apoplast? | back 12 the lumen of a sieve tube |
front 13 Pine seedling grown in sterile potting soil grow much slower than seedlings grown in soil from the area where the seeds were collected. This is most likely because | back 13 the normal symbiotic fungi are not present in the sterilized soil and water and mineral uptake is faster when mycorrhizae are present |
front 14 Which one of the following statements about transport of nutrients in phloem is false? | back 14 companion cells control the rate and direction of movement in phloem sap |
front 15 All of the following has an effect on water potential in plants except | back 15 DNA structure |
front 16 If the guard cells and surrounding epidermal cells in a plant are deficient in potassium ions, all of the following would occur except | back 16 leaf temperatures would decrease |
front 17 Which of the following statements about transport in plants in false? | back 17 Gymnosperms can sometimes develop especially high root pressure, which may account for the rise of water in tall pine trees without transpiration pull |
front 18 Photosynthesis begins to decline when leaves wilt because | back 18 stomata close, preventing CO2 entry into the leaf |
front 19 Active transport of various materials in plants at the cellular level requires all of the following except | back 19 xylem membranes |
front 20 movement of phloem sap from source to sink | back 20 may translocated sugars from the breakdown of stored starch in a root up to developing shoots |
front 21 What would enhance water uptake by a plant cell? | back 21 positive pressure on the surrounding solution |
front 22 Which of the following has the lowest (most negative) water potential_ | back 22 leaf air spaces |
front 23 Transpiration in plants requires all of the following except | back 23 active transport through xylem cells |
front 24 Which of the following statements is false concerning the xylem? | back 24 movement of materials is by mass flow; materials move owing to a turgor pressure gradient from "source" to "sink" |
front 25 Active transport involves all of the following except the | back 25 diffusion of solute through the lipid bilayer of a membrane |
front 26 Active transport would be least important in the normal functioning of which of the following plant tissue types? | back 26 stem xylem |
front 27 All of the following are adaptations that help reduce water loss from a plant except | back 27 transpiration |
front 28 Water flows into the source end of sieve tube because | back 28 sucrose has been actively transported into the sieve tube, making it hypertonic |
front 29 The water lost during transpiration is an unfortunate side effect of the plant's exchange of gases. However, the plant derives some benefit from this water loss in the form of | back 29 evaporative cooling and mineral transport |
front 30 Some botanists argue that the entire plant should be considered as a single unit rather than a composite of many individual cells. Which of the following cellular structures cannot be used to support this view? | back 30 tonoplast |
front 31 Long-distance electrical signaling in the phloem has been shown to elicit a change in all of the following except | back 31 a switch from C4 to C3 photosynthesis |
front 32 Stomata open when guard cells | back 32 open because of a decrease in turgor pressure |
front 33 Root hairs are most important to a plant because they | back 33 increase the surface area for absorption |
front 34 What is the role of proton pumps in root hair cells? | back 34 acquire minerals from the soil |
front 35 All of the following normally enter the plant through the roots except | back 35 carbon dioxide |
front 36 What regulates the flow of water through the xylem? | back 36 the evaporation of water from the leaves |
front 37 If you were to prune the shoot tips of a plant, what would be the effect on the plant and leaf area index? | back 37 bushier plants - higher leaf area indexes |
front 38 A fellow student brought in a leaf to be examined. The leaf was dark green, thin, had a stoma on the lower surface only, and had a surface area of 100 square meters. Where is the most likely environment where this leaf was growing? | back 38 a tropical rain forest |
front 39 A water molecule could move all the way through a plant from soil to root to leaf to air and pass through a living cell only once. This living cell would be part of which structure? | back 39 the endodermis |
front 40 Water potential is generally most negative in which of the following parts of the plant? | back 40 mesophyll cells of the leaf |
front 41 Guard cells do which of the following? | back 41 help balance the photosynthesis-transpiration compromise |
front 42 Xylem vessels, found in angiosperms, have a much greater internal diameter than tracheids, the only xylem conducting cells found in gymnosperms. The tallest living trees, redwoods, are gymnosperms. Which of the following is an advantage of tracheids over vessels for long-distance transport to great heights? | back 42 cohesive forces are greater in narrow tubes than in wide tubes of the same height, and adhesive forces are proportionally greater in narrower cylinders than in wider cylinders |
front 43 The amount and direction of movement of water in plants can always be predicted by measuring which of the following? | back 43 water potential |
front 44 Which of the following experimental producers would most likely reduce transpiration while allowing for normal growth of a plant? | back 44 increasing the level of carbon dioxide around the plant |
front 45 Which of the following is not an important component of the long-distance transport process in plants? | back 45 the root parenchyma |
front 46 Which of the following best explains why CAM plants are not tall? | back 46 they wold be unable to move water and minerals to the top of the plant during the day |
front 47 Phloem transport of sucrose can be described as going from "source to sink." Which of the following would not normally function as a sink? | back 47 mature leaf |
front 48 As a biologist, it is your job to look for plants that have evolved structures with a selective advantage in dry, hot conditions. Which of the following adaptations would be least likely to meet your objective? | back 48 plants that do not produce abscisic avid and have a short, thick taproot |
front 49 A plant developed a mineral deficiency after being treated with fungicide. What is the most probable cause of the deficiency? | back 49 mycorrhizal fungi were killed |
front 50 Which of the following is responsible for the cohesion of water molecules? | back 50 hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule |
front 51 All of the following involves active transport across membranes except | back 51 the movement of sugar from one sieve-tube member to the next |
front 52 Which of the following is an adaptation that enhances the uptake of water and minerals by roots? | back 52 active uptake |
front 53 What is the driving force for the movement of materials in the phloem of plants? | back 53 a difference in osmotic water potential between the source and the sink |
front 54 Which of the following would be least likely to affect osmosis in plants? | back 54 receptor proteins in the membrane |
front 55 Which of the following does not affect self-shading? | back 55 stem thickness |
front 56 Which of the following is not a function of the plasma membrane proton pump? | back 56 equalizes the charge on each side of a membrane |
front 57 What is the main force by which most of the water within xylem vessels moves toward the top of a tree? | back 57 evaporation of water through stoma |
front 58 In which plant cell or tissue would the pressure component of water potential most often be negative? | back 58 stem xylem |
front 59 The following factors may sometimes play a role in the movement of sap through xylem. Which one depends on the direct expenditure of ATP by the plant? | back 59 concentration of ions in the symplast |
front 60 The opening of stomata is thought to involve | back 60 an increase in osmotic concentration of the guard cells |
front 61 Compared to a cell with a few aquaporins in its membrane, a cell containing many aquaporins will | back 61 have a faster rate of osmosis |
front 62 Which of the following statements is false about bulk flow? | back 62 it depends on the force of gravity on the column of water |
front 63 Which of the following would likely not contribute to the surface area available for water absorption from the soil by a plant root system? | back 63 endodermis |
front 64 One is most likely to see guttation in small plants when the | back 64 root pressure exceeds transpiration pull |
front 65 Which structure or compartment is not part of the plant's apoplast? | back 65 the lumen of a sieve tube |
front 66 According to the pressure flow hypothesis of phloem transport | back 66 solute moves from a high concentration in the "source" to a lower concentration in the "sink" |
front 67 Which of the following statements about xylem is incorrect? | back 67 it transports mainly sugars and amino acids |
front 68 Water rises in plants primarily by the cohesion-tension model. Which of the following is not true about this model? | back 68 the "tension" of this model represents the excitability of the xylem cells |
front 69 Which of the following is not part of the transpiration-cohesion-tension mechanism for the ascent of xylem sap? | back 69 active pumping of water into the xylem of roots |