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MCQOPTIONS
This section includes 200950 Mcqs, each offering curated multiple-choice questions to sharpen your General Knowledge knowledge and support exam preparation. Choose a topic below to get started.
| 12201. |
Subtraction of which of the following will convert gross primary productivity into net primary productivity? |
| A. | the energy used by autotrophs in respiration |
| B. | the energy fixed by photosynthesis |
| C. | all solar energy |
| D. | the energy contained in the standing crop |
| Answer» B. the energy fixed by photosynthesis | |
| 12202. |
Which of the following most directly relates to the current biodiversity crisis? |
| A. | increased atmospheric carbon dioxide |
| B. | ozone depletion |
| C. | the rate of extinction |
| D. | introduced species |
| Answer» E. | |
| 12203. |
The concept that energy cannot cycle through an ecosystem is best explained by |
| A. | the law of conservation of energy. |
| B. | the principle of biomagnification. |
| C. | the second law of thermodynamics. |
| D. | the competitive exclusion principle. |
| Answer» D. the competitive exclusion principle. | |
| 12204. |
The total biomass of photosynthetic autotrophs present in an ecosystem is known as the |
| A. | net primary productivity. |
| B. | standing crop. |
| C. | trophic efficiency. |
| D. | gross primary productivity. |
| Answer» C. trophic efficiency. | |
| 12205. |
The total number of extant species is approximately.. |
| A. | 1,000 to 50,000. |
| B. | 50,000 to 150,000. |
| C. | 500,000 to 1,000,000. |
| D. | 10,000,000 to 80,000,000. |
| Answer» E. | |
| 12206. |
The difference between net and gross primary productivity would likely be greatest for |
| A. | prairie grasses. |
| B. | phytoplankton in the ocean. |
| C. | corn plants in a farmer’s field. |
| D. | an oak tree in a forest. |
| Answer» E. | |
| 12207. |
In order to better understand the extent of current extinctions it will be necessary to do which of the following? |
| A. | Focus intensely on identifying more species of mammals and birds. |
| B. | Differentiate between plant extinction and animal extinction. |
| C. | Use the average extinction rates of vertebrates as a baseline. |
| D. | Identify more of the yet unknown species of organisms on our planet. |
| Answer» E. | |
| 12208. |
Which of the following terms includes all of the others? |
| A. | genetic diversity |
| B. | species diversity |
| C. | biodiversity |
| D. | ecosystem diversity |
| Answer» D. ecosystem diversity | |
| 12209. |
The most accurate assessments of current extinction rates probably come from studies of.. |
| A. | reptiles, because they are ectothermic and susceptible to population declines during frequent past glacial periods. |
| B. | birds and mammals, because they are relatively well-known taxa. |
| C. | marine invertebrates, because of their relatively long and complete fossil history. |
| D. | insects, because they comprise the vast majority of extant multicellular organisms. |
| Answer» C. marine invertebrates, because of their relatively long and complete fossil history. | |
| 12210. |
Estimates of current rates of extinction.. |
| A. | indicate that we have reached a state of unstable equilibrium in which speciation and extinction rates are approximately equal. |
| B. | suggest that one-half of all animal and plant species may be gone by the year 2100. |
| C. | indicate that rates may be 1,000 times higher than at any other time in the last 100,000 years. |
| D. | B and C only are true. |
| Answer» E. | |
| 12211. |
Which of the following would not qualify as an ecosystem service? |
| A. | rain falling to Earth |
| B. | squirrels burying acorns |
| C. | leaves falling on a forest floor |
| D. | blowfly larvae infesting a deer carcass |
| Answer» B. squirrels burying acorns | |
| 12212. |
According to most conservation biologists, the single greatest threat to global biodiversity is. |
| A. | global climate change resulting from a variety of human activities. |
| B. | stratospheric ozone depletion. |
| C. | chemical pollution of water and air. |
| D. | alteration or destruction of the physical habitat. |
| Answer» E. | |
| 12213. |
Which of the following is a valid conclusion about the outcome of Biosphere II? |
| A. | Natural ecosystems are complex and not easily duplicated. |
| B. | Humans cannot live in small spaces for an extended period of time. |
| C. | Closed ecoystems must be made airtight. |
| D. | Small populations are more likely to go extinct. |
| Answer» B. Humans cannot live in small spaces for an extended period of time. | |
| 12214. |
The Nile perch (Lates niloticus) is a good example of a(n) |
| A. | endangered endemic. |
| B. | primary consumer. |
| C. | population sink. |
| D. | introduced predator. |
| Answer» E. | |
| 12215. |
Which of the following was not presented as an example of an introduced species? |
| A. | red foxes in Australia |
| B. | timber wolves in Minnesota |
| C. | starlings in New York |
| D. | zebra mussels in the Great Lakes |
| Answer» C. starlings in New York | |
| 12216. |
In Hen the egg is fertilized at the stage of.. |
| A. | Primary oocyte |
| B. | Secondary oocyte |
| C. | Ootid |
| D. | Both A and B |
| Answer» C. Ootid | |
| 12217. |
Which of the following does not represent a potential threat to biodiversity? |
| A. | importing a European insect into the United States to control an undesirable weed |
| B. | letting previously used farmland go fallow and begin to fill with weeds and shrubs |
| C. | building a new mall on a previously unoccupied piece of midwestern prairie. |
| D. | harvesting all of the oysters from an oyster bed off the Atlantic coast |
| Answer» C. building a new mall on a previously unoccupied piece of midwestern prairie. | |
| 12218. |
In Hen the egg is released from the ovary as.. |
| A. | Primary oocyte |
| B. | Secondary oocyte |
| C. | Ootid |
| D. | None of these |
| Answer» B. Secondary oocyte | |
| 12219. |
Which of the following is a method of predicting the likelihood that a species will persist in a particular environment? |
| A. | source-sink analysis |
| B. | minimum viable population size |
| C. | population dynamic analysis |
| D. | population viability analysis |
| Answer» E. | |
| 12220. |
All of the following apply to the concept of the extinction vortex except: |
| A. | Populations of the species entering it are small. |
| B. | It is a concept developed by conservation biologists who adopt the “small population approach.” |
| C. | The genetic variation of the species’ population decreases. |
| D. | The key factor driving the extinction vortex is intraspecific competition. |
| Answer» E. | |
| 12221. |
Introduced species can have important effects on biological communities by. |
| A. | preying upon native species. |
| B. | displacing native species. |
| C. | competing with native species for resources. |
| D. | doing all of the above. |
| Answer» E. | |
| 12222. |
The egg of Hen is : |
| A. | Alecithal |
| B. | Meolecithal |
| C. | Mesolecithal |
| D. | Polylecithal |
| Answer» E. | |
| 12223. |
The correct sequence of process of development after fertilization and cleavage is. |
| A. | Gastrulation-Organogenesis-Growth |
| B. | Organogenesis-Gastrulation-Growth |
| C. | Gastrulation-Blastulation-Growth |
| D. | Organogenesis-Morulation-Blastulation |
| Answer» B. Organogenesis-Gastrulation-Growth | |
| 12224. |
One of the most important correlative effects in plants is: |
| A. | Morphogenesis |
| B. | Apical dominance |
| C. | De-differentiation |
| D. | Re-differentiation |
| Answer» C. De-differentiation | |
| 12225. |
It is series of mitotic cell division that changes zygote into multicellular embryo. |
| A. | Gastrulation |
| B. | Gametogenesis |
| C. | Blastulation |
| D. | Cleavage |
| Answer» E. | |
| 12226. |
Cell divisions, migrations, and rearrangements produce three germ layers in.. |
| A. | Morulation |
| B. | Blastulation |
| C. | Gastrulation |
| D. | All, A, B and C |
| Answer» D. All, A, B and C | |
| 12227. |
During the process of ________ the miniature seedling comes and enter the second phase ___________. |
| A. | Fertilization, Development |
| B. | Fertilization, Cleavage |
| C. | Germination, Growth |
| D. | Cleavage, Differentiation |
| Answer» D. Cleavage, Differentiation | |
| 12228. |
._________are parts of apical meristem which have become separated from the apex by permanent tissues. |
| A. | Primary meristem |
| B. | Intercalary meristem |
| C. | Lateral meristem |
| D. | None of the above |
| Answer» C. Lateral meristem | |
| 12229. |
The removal of apex releases the lateral buds from apical dominance, it is known as |
| A. | Inhibitory effect |
| B. | Reciprocal effect |
| C. | Compensatory effect |
| D. | Apical effect |
| Answer» D. Apical effect | |
| 12230. |
In Crassulacean Acid Metabolism (CAM) plants : |
| A. | phosphoenolpyruvate carboxylase reduces CO2 to make malic acid |
| B. | stomata open only during the day |
| C. | vascular tissue is surrounded by a bundle sheath |
| D. | rubisco is activated only at night |
| Answer» B. stomata open only during the day | |
| 12231. |
The Chemiosmotic Theory : |
| A. | explains the evolutionary origin of chioroplasts and mitochondria |
| B. | describes how energy is transferred from antenna pigment to reaction center |
| C. | is a failed attempt to explain why plants photorespire |
| D. | describes the coupling of ATP synthesis to electron transport chains |
| Answer» E. | |
| 12232. |
When Rubisco acts as an oxygenase.. |
| A. | phosphoglycerate and phosphoglycolate are produced |
| B. | phosphoenolpyruvate (PEP) is oxidized |
| C. | net carbon fixation is enhanced |
| D. | it must mean that the plant is deprived of CO2 |
| Answer» B. phosphoenolpyruvate (PEP) is oxidized | |
| 12233. |
Antenna pigments transfer light energy to the reaction center.. |
| A. | by means of fluorescence |
| B. | through a process known as inductive resonance |
| C. | in order to dissipate excess light energy |
| D. | with relatively low efficiency |
| Answer» C. in order to dissipate excess light energy | |
| 12234. |
The compound identified by Calvin, Benson, and Bassham as the first one made by CO2 fixation is: |
| A. | ribulose bisphosphate |
| B. | phosphoglycerate |
| C. | triose-phosphate |
| D. | malate |
| Answer» C. triose-phosphate | |
| 12235. |
The Calvin Cycle is regulated : |
| A. | by levels of ATP and NADPH |
| B. | by the movement of magnesium across the thylakoid membrane |
| C. | by the activity of ribulose bisphosphate carboxylase-oxygenase |
| D. | all of the above |
| Answer» E. | |
| 12236. |
Triose-phosphate is used : |
| A. | in starch synthesis |
| B. | in sucrose synthesis |
| C. | in RuBP regeneration |
| D. | all of the above |
| Answer» E. | |
| 12237. |
Which of the following biochemical processes consumes O2 and yields CO2? |
| A. | photosynthesis |
| B. | photorespiration |
| C. | respiration |
| D. | both b and c |
| Answer» E. | |
| 12238. |
Thylakoid membranes : |
| A. | are the only site of ATP synthesis in plant cells |
| B. | separate the matrix from the intermembrane space |
| C. | are home to all photosynthetic pigments |
| D. | contain a triose-P/Pi antiport protein |
| Answer» D. contain a triose-P/Pi antiport protein | |
| 12239. |
If the lower leaves of a plant are below the light compensation point : |
| A. | they will fix more carbon than they respire |
| B. | they will respire more carbon than they fix |
| C. | they will fix as much carbon as leaves at the top of the plant |
| D. | synthesis of carotenoids will double |
| Answer» C. they will fix as much carbon as leaves at the top of the plant | |
| 12240. |
Respiration : |
| A. | Involves the use of electron transport chains |
| B. | Involves the breakdown of glucose to form high energy compounds |
| C. | has steps which occur in both the cytoplasm and mitochondria |
| D. | a,b, and c are correct |
| Answer» E. | |
| 12241. |
The Optimum Leaf Area Index (LAI) for a particular plant : |
| A. | is the LAI where net photosynthesis rate (or productivity) of the plant is at a maximum |
| B. | is always |
| C. | is the maximum leaf area that a plant can support on its stem |
| D. | is the LAI where the most ground area is covered |
| Answer» B. is always | |
| 12242. |
Which of the following is not a function of the large central vacuole of a plant cell: |
| A. | maintenance of turgidity |
| B. | sequestration of toxic ions |
| C. | a temporary repository of sugars |
| D. | a site of some reactions of photorespiration |
| Answer» E. | |
| 12243. |
Which of the following is not a regulatory factor of carbon fixation: |
| A. | the level of acetyl-CoA in the chloroplast stroma |
| B. | the levels of ATP and NADPH in the stroma |
| C. | pH of the stroma |
| D. | Mg++ level in the stroma |
| Answer» B. the levels of ATP and NADPH in the stroma | |
| 12244. |
Antenna pigments transfer light energy to a reaction center : |
| A. | by means of a process known as fluorescence |
| B. | by means of a process known as inductive resonance (direct transfer of energy) |
| C. | by the conduction of heat |
| D. | a,b, and c are all correct |
| Answer» C. by the conduction of heat | |
| 12245. |
African plant Pentadiplandra is used as______. |
| A. | Low calories sweetner |
| B. | 2000 times sweeter agent |
| C. | Sweetner for diabetic patients |
| D. | All of these |
| Answer» E. | |
| 12246. |
The most abundant component in the cell wall of a growing plant is : |
| A. | cellulose |
| B. | protein |
| C. | water |
| D. | nucleic acids |
| Answer» D. nucleic acids | |
| 12247. |
After mitotic division, the first component of the plant cell wall deposited is the middle lamella. It is primarily composed of : |
| A. | pectin (or a salt of pectin) |
| B. | cellulose |
| C. | golgi bodies |
| D. | hemicelluloses |
| Answer» B. cellulose | |
| 12248. |
Callus is : |
| A. | Tissue that forms embryo |
| B. | an insoluble carbohydrate |
| C. | Unorganised actively dividing mass of cells maintained in culture |
| D. | Tissue that growth to form embryoid |
| Answer» D. Tissue that growth to form embryoid | |
| 12249. |
To raising of plants from a small tissue in culture is known as |
| A. | Micropropagation |
| B. | Macroproduction |
| C. | Tissue culture |
| D. | Mass production |
| Answer» B. Macroproduction | |
| 12250. |
Biopatents are ______. |
| A. | Right to use invention |
| B. | Right to use biological entities |
| C. | Right to use products |
| D. | Right to use process |
| Answer» C. Right to use products | |