Pictures
Definitions
True/False
Scenario
Otter Trivia
100
At what pH does this testing strip appear to be?
~2
100
Non-living.
Abiotic
100
Temperature is an abiotic factor.
True
100
A population of brightly colored reef fish lives among coral reefs in shallow, clear waters. Over several years, ocean temperatures rise and cause coral bleaching, turning the reefs white and reducing the fish’s camouflage. Predatory barracudas begin catching these fish more easily. After several generations, more of the surviving fish have duller, grayish coloration that blends better with the pale coral.
What is the selective pressure acting on this fish population?
The predation by the barracudas
100
True or false: the sea otter is part of the marsupial family.
False! Sea otters are part of the weasel family!
200
If the producers have 6.3 million kcal, how much energy will the secondary consumers have?
63,000 kcal (10% rule)
200
having a pH of 0-6
Acidic
200
The atmospheric carbon dioxide levels are maintaining homeostasis.
False.
200
A population of freshwater mussels lives in a river that’s gradually becoming more acidic due to runoff from nearby farms. Within the mussel population, some individuals can tolerate lower pH levels because their shells are thicker and less likely to dissolve, while others with thinner shells are more vulnerable to the acidic water. Over several generations, the population becomes dominated by mussels with thicker shells.
What trait is being selected for, and what trait is being selected against in this mussel population?
Selected for: thicker shells
Selected against: thinner shells
200
How much do sea otters typically weigh? (in pounds, has to be within the range of the answer)
40-90 lbs.
300
Name one abiotic and one biotic factor you see in this picture.
abiotic: heat, sun, space
biotic: bacteria, animals, plants, fungi
300
If it is removed, the ecosystem will fall apart.
Keystone species
300
Organisms can be categorized in multiple trophic levels at a time.
True
300
In a large freshwater pond, populations of algae, fish, and aquatic insects have remained relatively stable for several years. Recently, fertilizer runoff from nearby farms has entered the pond, causing algae to grow rapidly. The thick mats of algae block sunlight from reaching underwater plants, which begin to die off. As the plants die, oxygen levels in the water decrease, and many fish are found floating at the surface.
No: the algae blooms are not decreasing and it is causing additional changes in the ecosystem that are not going back to the normal stable baseline.
300
How long can sea otters hold their breath?
Up to 5 minutes
400
At what year in this graph is it reasonable to say the otter population started to decrease based on the urchin population?
2013-2014, after those years, the urchin population starts to skyrocket and it is reasonable to guess it is because they have fewer predators.
400
Ability of ecosystems to maintain a relatively constant environment despite external factors.
Homeostasis.
400
Plants get nitrogen directly from waste.
False: bacteria must convert it into a form that is able to be taken up and used by plants.
400
In a mountain lake ecosystem, the population of trout has been steadily declining. Over the past several years, water temperatures have risen and oxygen levels have dropped due to warmer summers and reduced snowmelt feeding the lake. At the same time, an invasive crayfish species has been introduced and preys on trout eggs. Algae blooms have also become more common, fueled by increased nutrient runoff from nearby farms. Additionally, a viral infection has begun spreading through the trout population, making them weaker and less likely to reproduce successfully.
Name one biotic factor affecting the trout population.invasive crayfish or algae blooms
400
What is a group of resting sea otters called?
A raft
500
This is a graph of sea surface temperatures over time. Does this look like an ecosystem in homeostasis? Why or why not?
No: the temperature is steadily increasing, and not coming back to the stable baseline it used to be at.
500
the process by which organisms who are better adapted to their environment are more likely to survive and reproduce, eventually changing the frequency of traits in the population over time.
Natural Selection
500
Seawater normally has a neutral pH.
False: seawater naturally has a pH of 8.0-8.3, which is slightly basic
500
In a coastal salt marsh ecosystem, cordgrass provides food and shelter for many species. Small crabs feed on detritus (decaying plant material) around the grass roots, while snails graze on algae that grow on the grass stems. Egrets and herons feed on the crabs and snails. Recently, scientists have noticed a sharp decline in the egret population due to habitat loss in nearby nesting areas.
Name two other species the loss of the egrets would have an effect on in this food web, and how they are effected.
Answers vary and will be assessed as given.
500
Where do sea otters tend to store their favorite pebbles?
In pockets of loose fur (pouches) under their forearms.