©Jason MacConnell 2025 ALL RIGHTS RESERVED.
UW Ocean 101 Exam 3 Questions With
Correct Answers A+
Identify the major types of plants, algae, and animals - Answer✔plants: seagrasses.
algae: green, brown (kelp), red.
animals: anemones, barnacles, marine snails, limpets, mussels, crabs, sea stars.
Identify the three tidal zones described in class - Answer✔supra littoral: 'splash zone'. always
exposed because it's above the high tide line. marine animals live here.
mid littoral: covered during high tide, exposed during low tide. marine animals live here.
lower littoral: always covered because it's below the low tide line. plants and algae live here.
Describe the factors that govern vertical zonation of the rocky shore - Answer✔physical: Tides
(exposure time), Temperature, Wave Action, Salinity, Oxygen stress
Biological: Recruitment/Settlement, Competition, Predation
Define the term food chain and web - Answer✔food chain: a sequence of transfers of matter and
energy in the form of food from organism to organism.
food web: more complex and is a whole system of connected food chains.
who eats who in the intertidal - Answer✔plants and algae are primary producers. chittons,
limpets, and snails are scrapers. barnacles eat plankton and small animals. mussels are eaten by
sea stars, marine snails, and anemones (which also eat fish and crabs).
Identify the adaptations that the intertidal organisms have developed to survive and thrive in the
intertidal - Answer✔resistance to desiccation: shells, ability to close shell completely and seal in
moisture
attachment: some organisms produce and glue that can adhere them to a surface.
food source/feeding type: autotrophs or heterotrophs. filter feeders or scrapers/grazers.
wave action adaptions: be small, smooth, sessile, flexible, be able to regrow and find shelter.
Identify the major types of phytoplankton and list the major determining characteristics (size,
shell material, motility) of each group - Answer✔diatoms: unicellular, silica frustrule, asexual.
, ©Jason MacConnell 2025 ALL RIGHTS RESERVED.
dinoflagellates: 2 flagella, unicellular, half are heterotrophic (mixotrophs) and half are
autotrophs.
coccolithophores: carbonate scales/plates, occur in blooms, unicellular.
cyanobacteria: blue-green algae, oldest life form on earth, photosynthetic bacteria, equally
important as diatoms.
Explain why phytoplankton are important in the world oceans - Answer✔base of the food chain,
produce most of earth's oxygen, most important primary producers in the ocean
Define photosynthesis and describe the requirements for photosynthesis -
Answer✔photosynthesis: production of organic compounds from co2 and h2o using sunlight as
an energy. requires the nutrients nitrogen and phosphorus. produces o2.
List the major nutrients required for photosynthesis - Answer✔nitrogen and phosphorus.
Understand the role of carbon dioxide (CO2) and oxygen (O2) in biological cycles, especially
primary production and respiration - Answer✔photosynthesis requires co2 and produces o2.
respiration and decomposition require o2 and produces co2.
Describe how the concentrations of major nutrients change with distance from land and depth in
the water column - Answer✔nutrient concentration increases with ocean depth and decreases
with increased distance from the shore.
Explain why upwelling conditions are favorable for phytoplankton growth - Answer✔upwelling
is favorable because it brings up cold, nutrient rich water to the surface which phytoplankton can
use.
Identify the major types of heterotrophs in the oceans - Answer✔zooplankton, bacteria and
archaea, viruses
Describe the role of microbes in the biological cycles, and how they influence carbon dioxide
(CO2) and oxygen (O2) - Answer✔they're decomposers or recyclers. use organic matter in
dissolved or particulate form. eat dying things. they comsume o2 and produce co2.
Explain what controls the productivity of Washington waters - Answer✔light, nutrients, grazing,
water column mixing/stratification/turbidity
Explain the bottom up/top down control of production - Answer✔bottom up: biomass is
controlled by the availability of food or energy. (light, nutrient, water column
stratification/stability).
top down: biomass is controlled by consumption. (zooplankton graze phytoplankton.)
Define the terms benthic and benthos - Answer✔benthic is the ocean floor. benthos are the
organisms that live in the benthic zone.
