Biol 271 Exam Questions with
Correct Answers 100% PASS
Functional roles of ponifera - CORRECT ANSWER-• Spatial competitors
• Filter huge quantities of water
• Bioeroders
• Sources of novel compounds
• Agents of biological disturbance
• Facilitate primary production
Ponifera can also have functional roles related to their food web, such as -
CORRECT ANSWER-• Habitat provision
• Food source
• Substrate stabilisation and consolidation
• Influencing near substration boundary layers.
ponifera functional roles via tropic position - CORRECT ANSWER-• Move water
in large quantities
,• Dissolved organic carbon is able to be absorbed by sponges in the sponge loop as
food and shedding chonaocytes. This moves the carbon up trophic levels.
Food webs and components - CORRECT ANSWER-Organisms can have benthic
or pelagic habitats. Benthic means associated with the sea floor. Pelagic means
associated with the open water. This is an important distinction between organisms
Primary producers - CORRECT ANSWER-• Photosynthetic organisms
• Pelagic- phytoplankton; diatoms, dinoflagellates
• Benthic- macroalgae, diatoms
Grazers/herbivores - CORRECT ANSWER-• Pelagic- copepods directly feed on
phytoplankton
• Benthic- urchins, fish, gastropods
Suspension/filter feeders - CORRECT ANSWER-• Simple filterers
• Ciliary activity using mucus
• Pelagic- amphipods, fish, baleen whales
• Benthic- molluscs, sponges, ascdians, barnacles, anemones, fish
Predators - CORRECT ANSWER-• Pelagic- squid, killer whales, birds, seals, sea
lions, dolphins, porpoises, sharks
• Benthic- starfish, octopus, fish, sea otter.
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,Parasites - CORRECT ANSWER-Parasites are also a trophic level and are
involved in food nets by eating the food or the organism that something else feeds
on
Trophic relationship - CORRECT ANSWER-Movement through the food web
via trophic levels. Food webs can be simple or complex, but will always have
trophic levels. Animals can feed from multiple trophic levels. Benthic and Pelagic
ecosystems are interlinked
Adaptations - CORRECT ANSWER-adapt to temperature, light, oxygen
concentration, salinity, and fluctuations of these in their environment. In some of
the environments the fluctuations can be intense. Adaptations can also be used to
defend against pregatirs and reduce competitions. Adaptations also have to ensure
reproduction and dispersal.
Osmoregulation definition - CORRECT ANSWER-the maintenance of osmotic
pressure in the fluids of an organism by the control of water and salt
Osmoregulation - CORRECT ANSWER-Organisms can either be conformers or
regulators. Regulators can be hyper or hypo osmotic. Osmoconformers are
isosmotic but can actively move solutes. Animals can regulate osmosis by active
transport, changing permeability of the membranes, and altering concentration
gradients.
, regulator problems - CORRECT ANSWER-When an organism is hyperosmotic it
has 2 problems. Water flows in and solutes are lost. When it is hypo osmotic is has
the opposite problems
stenohaline - CORRECT ANSWER-can't tolerate reduced salinity
euryhaline - CORRECT ANSWER-can withstand reduced salinity or brackish
animals
Brackish water animals - CORRECT ANSWER-Brackish water animals can have
some conformers and some regulators. Are found in the salinity range of 5-18ppt.
Competition and predation limit seaward extent of their range
Nereis divesicolor - CORRECT ANSWER-tolerates wide salinity. When placed
into dilute seawater it takes up water by osmosis.
Palemoeties - CORRECT ANSWER-shrimp. They are hypotonic in seawater. It is
a hyporegulator
other strategies for osmoregulation - CORRECT ANSWER-shutting up shop or
becoming impermeable to water
Teleosts - CORRECT ANSWER-drink large quantities of water and remove ions
via active transport from the gills. A fish moving between seawater and freshwater
can change its urine production (low in seawater, high in freshwater).
Elasmobranchs - CORRECT ANSWER-are isosmotic with sea water. They do this
by using urea and trimethylamine oxide to maintain osmotic pressure.
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protected by copyright law
Correct Answers 100% PASS
Functional roles of ponifera - CORRECT ANSWER-• Spatial competitors
• Filter huge quantities of water
• Bioeroders
• Sources of novel compounds
• Agents of biological disturbance
• Facilitate primary production
Ponifera can also have functional roles related to their food web, such as -
CORRECT ANSWER-• Habitat provision
• Food source
• Substrate stabilisation and consolidation
• Influencing near substration boundary layers.
ponifera functional roles via tropic position - CORRECT ANSWER-• Move water
in large quantities
,• Dissolved organic carbon is able to be absorbed by sponges in the sponge loop as
food and shedding chonaocytes. This moves the carbon up trophic levels.
Food webs and components - CORRECT ANSWER-Organisms can have benthic
or pelagic habitats. Benthic means associated with the sea floor. Pelagic means
associated with the open water. This is an important distinction between organisms
Primary producers - CORRECT ANSWER-• Photosynthetic organisms
• Pelagic- phytoplankton; diatoms, dinoflagellates
• Benthic- macroalgae, diatoms
Grazers/herbivores - CORRECT ANSWER-• Pelagic- copepods directly feed on
phytoplankton
• Benthic- urchins, fish, gastropods
Suspension/filter feeders - CORRECT ANSWER-• Simple filterers
• Ciliary activity using mucus
• Pelagic- amphipods, fish, baleen whales
• Benthic- molluscs, sponges, ascdians, barnacles, anemones, fish
Predators - CORRECT ANSWER-• Pelagic- squid, killer whales, birds, seals, sea
lions, dolphins, porpoises, sharks
• Benthic- starfish, octopus, fish, sea otter.
© 2026 Copyright. All Rights Reserved. This document is
protected by copyright law
,Parasites - CORRECT ANSWER-Parasites are also a trophic level and are
involved in food nets by eating the food or the organism that something else feeds
on
Trophic relationship - CORRECT ANSWER-Movement through the food web
via trophic levels. Food webs can be simple or complex, but will always have
trophic levels. Animals can feed from multiple trophic levels. Benthic and Pelagic
ecosystems are interlinked
Adaptations - CORRECT ANSWER-adapt to temperature, light, oxygen
concentration, salinity, and fluctuations of these in their environment. In some of
the environments the fluctuations can be intense. Adaptations can also be used to
defend against pregatirs and reduce competitions. Adaptations also have to ensure
reproduction and dispersal.
Osmoregulation definition - CORRECT ANSWER-the maintenance of osmotic
pressure in the fluids of an organism by the control of water and salt
Osmoregulation - CORRECT ANSWER-Organisms can either be conformers or
regulators. Regulators can be hyper or hypo osmotic. Osmoconformers are
isosmotic but can actively move solutes. Animals can regulate osmosis by active
transport, changing permeability of the membranes, and altering concentration
gradients.
, regulator problems - CORRECT ANSWER-When an organism is hyperosmotic it
has 2 problems. Water flows in and solutes are lost. When it is hypo osmotic is has
the opposite problems
stenohaline - CORRECT ANSWER-can't tolerate reduced salinity
euryhaline - CORRECT ANSWER-can withstand reduced salinity or brackish
animals
Brackish water animals - CORRECT ANSWER-Brackish water animals can have
some conformers and some regulators. Are found in the salinity range of 5-18ppt.
Competition and predation limit seaward extent of their range
Nereis divesicolor - CORRECT ANSWER-tolerates wide salinity. When placed
into dilute seawater it takes up water by osmosis.
Palemoeties - CORRECT ANSWER-shrimp. They are hypotonic in seawater. It is
a hyporegulator
other strategies for osmoregulation - CORRECT ANSWER-shutting up shop or
becoming impermeable to water
Teleosts - CORRECT ANSWER-drink large quantities of water and remove ions
via active transport from the gills. A fish moving between seawater and freshwater
can change its urine production (low in seawater, high in freshwater).
Elasmobranchs - CORRECT ANSWER-are isosmotic with sea water. They do this
by using urea and trimethylamine oxide to maintain osmotic pressure.
© 2026 Copyright. All Rights Reserved. This document is
protected by copyright law
