Quiz on Skills and Strategies

A student observes a cell under a microscope and notices it has a cell wall, a large central vacuole, and chloroplasts. Which type of cell is the student most likely observing?

• Animal cell

• Bacterial cell

• Plant cell

• Fungal cell

Which of the following best describes the function of the mitochondria in a cell?

• It controls what enters and exits the cell

• It converts glucose and oxygen into usable energy (ATP) for the cell

• It stores the cell's genetic information

• It produces proteins for the cell

A scientist is studying two ecosystems: a tropical rainforest and a desert. The rainforest contains over 1,000 species of plants, 400 species of birds, and 300 species of mammals. The desert contains 50 species of plants, 30 species of birds, and 10 species of mammals. Using this data, explain which ecosystem has greater biodiversity and describe one reason why high biodiversity is important for ecosystem stability.

• The desert has greater biodiversity because it has fewer species, making it easier for each species to survive

• Both ecosystems have equal biodiversity because they both contain plants, birds, and mammals

• The rainforest has greater biodiversity; high biodiversity increases ecosystem stability because if one species disappears, others can fill similar roles

• The rainforest has greater biodiversity, but this makes it more fragile because there is more competition for resources

In an ecosystem, which of the following correctly describes the role of decomposers?

• They produce their own food using sunlight through photosynthesis

• They hunt and consume other animals for energy

• They break down dead organisms and recycle nutrients back into the ecosystem

• They compete with producers for space and sunlight

A cell membrane is described as "selectively permeable." Based on your understanding of cell structure and function, explain what this means and why it is important for the cell's survival.

• The cell membrane allows all substances to pass through freely, ensuring the cell gets everything it needs

• The cell membrane blocks all substances from entering or leaving, protecting the cell from harm

• The cell membrane only allows certain substances to pass through, helping the cell maintain a stable internal environment

• The cell membrane changes its structure depending on the temperature of the environment

Which of the following is an example of a symbiotic relationship known as mutualism?

• A tapeworm living inside a dog's intestines and absorbing nutrients from the dog

• A clownfish living among sea anemone tentacles, where both organisms benefit

• A barnacle attaching to a whale's skin without harming or helping the whale

• A lion hunting and eating a zebra

In a grassland ecosystem, a disease wipes out 90% of the grass population. Using your knowledge of organism interactions and food webs, predict and explain at least two effects this event would have on other organisms in the ecosystem.

• Only the organisms that directly eat grass would be affected; all other organisms would remain unaffected

• Herbivores that eat grass would decline in population, which would then cause carnivores that eat those herbivores to also decline, disrupting the entire food web

• Carnivores at the top of the food chain would increase in population because there would be less competition for food

• Decomposers would immediately restore the grass population, so no other organisms would be significantly affected

Which of the following best describes the difference between a habitat and a niche?

• A habitat is the role an organism plays in its ecosystem, while a niche is the physical place where an organism lives

• A habitat is the physical place where an organism lives, while a niche includes the organism's role, diet, behavior, and interactions in the ecosystem

• A habitat and a niche are the same thing and can be used interchangeably

• A habitat refers only to aquatic environments, while a niche refers only to land environments

Two species of birds live in the same forest and eat the same type of insects. Over time, scientists observe that one bird species begins to go extinct. Using your knowledge of organism interactions, identify the type of relationship occurring and explain how competition affects biodiversity in an ecosystem.

• This is an example of predation; predation always reduces biodiversity by eliminating weaker species

• This is an example of mutualism; both species benefit from sharing the same food source, but one eventually outcompetes the other

• This is an example of competition; when two species compete for the same limited resource, the less adapted species may decline or go extinct, which can reduce biodiversity

• This is an example of commensalism; one species benefits while the other is unaffected, leading to the extinction of the unaffected species

Which of the following correctly identifies a difference between prokaryotic and eukaryotic cells?

• Prokaryotic cells have a nucleus, while eukaryotic cells do not

• Eukaryotic cells have membrane-bound organelles and a true nucleus, while prokaryotic cells do not

• Prokaryotic cells are always larger than eukaryotic cells

• Eukaryotic cells do not have a cell membrane, while prokaryotic cells do