TMA2/BIO405

TMA: TMA2/BIO405

SCORE=9.50

BIO405 - Hydrobiology

Mr. Adams Abiodun (aadams@noun.edu.ng )

1 Plants or macrophytes in freshwater systems can be grouped according to their manner of growth. This include all but one of the following: emergent macrophytes floating-leaved macrophytes submerged macrophytes all of the options 2 Which of the following characterise a free-floating macrophyte? not rooted in the substrate and floating beneath the surface rooted in the substrate but with floating leaves rooted in the substrate but with leaves and flowers extending into the air, not rooted in the substrate and floating on the surface. 3 Which of these plants shows more buoyancy? aboreal plants terrestrial plants aquatic plants all of the options 4 The most important factor controlling the distribution of submerged aquatic plants is ---------- water humudity light temperature 5 Euryhaline organisms are ----------- tolerant organism and can survive in marine ecosystems water heat light salt 6 Zooplankton are tiny --------- suspended in the water column plants vertebrates leaves animals 7 All of these are distinct communities of benthic organisms except Infauna Epifauna Demersal all of the options 8 Plants, animals and bacteria are attached to the hard bottom or substrate like rocks or debris; are capable of movement; or lives on the sediment surface. This characteristics describes which of these? Demersal Infauna Epifauna non of the options 9 The most familiar of all the benthic organisms is the nfaunal benthos Demersal benthos Epifaunal benthos ll of the options 10 Benthic invertebrate communities are used as prime indicators of environmental conditions because they have limited mobility and thus are unable to avoid adverse conditions their life spans are long enough to reflect the effects of environmental stressors their communities are taxonomically diverse enough to respond to multiple types of stress all of the options 11 The energy that is used in every ecosystem ultimately comes from the sun in form solar energy potential energy kinetic energy sunlight solar energy 12 Energy from the sun is usually trapped and converted to chemical energy through the process of photosynthesis by ----------- organisms heterotrophic chemotrophic photoautotrophic all of the options 13 The Productivity of heterotrophs is called Tertiary Productivity Secondary Productivity Primary Productivity basic Productivity 14 Freshwater systems gain most of their energy from ---------- performed by aquatic plants and algae respiration transpiration photosynthesis evaporation 15 The photosynthetic rate measurements of freshwater systems depend upon the amount of light attenuating materials the abundance and frequency range of light absorbing pigments inside of photosynthesizing cells the total biomass of photosynthesizing cells all of the options 16 In aquatic systems, primary production is typically measured using which one of these techniques? fluorescence kinetics Stable isotopes of Oxygen variations in oxygen concentration within a sealed bottle all of the options 17 The amount of dissolved ---------- in a water body is frequently the key substance in determining the extent and kinds of organic life in the water body hydrogen carbon oxygen zinc 18 Abiotic environmental factors of aquatic ecosystems include all but one of the following , , and temperature salinity fauna flow 19 In aquatic systems, oxygen is fatal to many kinds of ------ bacteria aerobic anaerobic all of the options non of the options 20 Many freshwater organisms are intolerant of oxygen salt all of the options non of the options