Module 04 Study Guide
Directions:
Fill out this study guide to prepare for the Module 04 Online Quiz and Module 04 Oral Quiz.
Phytoplankton (Lessons 04.02, 04.03 & 04.04)
 What are phytoplanktons? plankton consisting of microscopic plants
 Know that the three adaptations that allow phytoplankton to float are: cavities in the center of their
cells, cells contain oils and fats, and spines around the cavities.
 Are phytoplanktons the base of the oceanic food chain? Yes.
 What things do phytoplanktons need to survive? Light, precursors for photosynthesis. Minerals.
 What percentage of the Earth’s oxygen are phytoplanktons responsible for producing?
 Which types of phytoplankton are responsible for red tide? The accumulation of toxins in fish and
shellfish, and the end result of poisoning of predatory mammals and birds.
 What negative effects can red tide cause for the marine environment?
 If upwelling aids in phytoplankton growth, would less upwelling affect phytoplankton
numbers? How? yes, it would decrease phytoplankton
 How does a decrease in phytoplankton affect the rest of the food web? You would have a
decrease in everything else (at least carnivorous things). Less phytoplankton, less zooplankton,
less small fish/ invertebrates, less large fish birds etc. less large mammals etc. .
 Know that harmful algal blooms do not cause erosion. Ok.
 If phytoplankton help reduce carbon dioxide on Earth, what would an increase amount of
phytoplankton do for carbon dioxide amounts? More phytoplankton would reduce carbon dioxide
Marine Iguanas (Lesson 04.07)
 What do marine iguanas primarily feed on? Marine algae
 What adaptations allow them to live and eat in the water? Hint: Know about their physical body
part changes that are different than their land ancestors. The short, blunt nose is well-adapted to
feeding on algae growing on rocks. The flattened tail is perfect for swimming, propelling the
iguana through the water while its legs hang useless at its sides. Iguanas rid themselves of excess
salt, consumed along with the algae, by a special gland connected to their nostrils.
 Where do the marine iguanas live? Hint: They are only found in this one area of the world.
Galapagos Islands
 Why do these cold-blooded organisms lay on the rocks instead of stay in the cold water? Because
they would get too cold in the water ad sitting on rocks warms them up.
 What is the main reason for their decline in population? The marine iguana may be endangered
due to predators. Marine iguanas don't have many predators in the ocean, but most of their
predators are on land. Baby iguanas are prey to birds such as hawks and herons. The introduction
of cats has also had a large impact of the population of marine iguanas. Iguanas are also affected
by oil spills.
Ms. Rechanek
Marine Science
Galapagos Islands (Lessons 04.04, 04.06 & 04.07)
 Why do the same species on different Galapagos Islands have slightly different traits? 1 Different
surroundings, they eat different things, they have different adaptions, and they have different
parents.
 What is the process of adapting to live more successfully and survive in a habitat called? The
process is called evolution. These organisms have adapted to their environment.
Food Chains/Webs (Lessons 04.08 & 04.09)
 Know order of organisms in a food chain: Primary producer and then consumers (primary,
secondary, tertiary and quaternary)
 Know the role of decomposers in the food chain. They eat dead plant and animal matter and
decomposes them- reduces them to similar forms of matter.
 Would bacteria be considered a decomposer? Yes because bacteria mostly feeds on dead
animals/plants and breaks them down.
 What happens to the 90% of energy that does not transfer to the next trophic level in a food chain?
 What amount of the original energy (from the producer) gets transferred to each level of a food
chain as you move up it? Hint: Remember 90% does not transfer. 10%
 Know how to choose organism types in a food chain. Example: phytoplankton = primary
producer; killer whale = tertiary (top) consumer.
 Create a food chain from a list of marine organisms. Hint: Typically the larger the organism, the
higher up on the food chain it would be. Phytoplankton, zooplankton, fish, seal, great white shark.
 Explain the difference between a food chain and a food web and mention which one most
resembles what occurs in an ecosystem. A food web a system of interlocking and interdependent
food chains. A food chain is a hierarchical series of organisms each dependent on the next as a
source of food.
 Are higher trophic level animals generally larger in size and fewer in numbers? Yes.
 Which organism in a food chain has the most energy? The producers have the most energy
because they are getting 100% of it from the sun. The organism that eats the producer only gets
10% of the energy and so on.
Next Steps:
Now it’s time to complete your Module 04 Oral Quiz! Please set up an appointment here for your oral
quiz: http://bit.do/oralquiz. You can also call/text me to set up an appointment. Remember that before you
complete the online quiz, we will need to complete the oral quiz for this module.
Ms. Rechanek
Marine Science