Biotic or Abiotic?
Is sunlight biotic or abiotic?
Abiotic.
A lion hunts a zebra. What relationship is this?
Predator-prey.
Why:
The lion is the predator and the zebra is the prey.
What is deforestation?
Answer:
The removal or cutting down of forests.
Why:
Deforestation destroys habitats and affects organisms that depend on trees.
This ecosystem has many tall trees, lots of rain, warm temperatures, and animals like monkeys, jaguars, frogs, and colorful birds.
Answer:
Tropical rainforest / jungle
What is the original source of energy for most ecosystems?
The Sun.
Why:
Plants use sunlight to make food through photosynthesis.
Is a dead leaf biotic or abiotic?
Biotic.
Why:
It came from a living organism, so it is still considered biotic.
Two plants grow close together and both need sunlight. What relationship is this?
Competition.
Why:
They are competing for the same resource.
How can pollution affect aquatic ecosystems?
It can poison organisms, reduce oxygen, damage habitats, and disrupt food chains.
Why:
Water quality is an abiotic factor that affects living things.
This ecosystem has salt water, waves, tides, plankton, fish, whales, sharks, and sea turtles.
Marine ecosystem / ocean
In this food chain, which organism is the producer?
grass → rabbit → fox
Grass.
Why:
Producers make their own food through photosynthesis.
A cactus lives in a desert. Name two abiotic factors that help determine whether it can survive there.
Heat, sunlight, little rain, sandy soil, or temperature.
Why:
Abiotic factors are non-living parts of the ecosystem that affect survival.
A bee drinks nectar from a flower and pollinates the flower. What relationship is this?
Answer:
Mutualism.
Why:
Both organisms benefit.
Why can introducing a new species into an ecosystem be dangerous?
It may become invasive and outcompete native species.
Why:
Invasive species can disrupt food chains and ecosystem balance.
This ecosystem has many grasses, few trees, grazing animals like zebras or antelopes, and predators like lions or hyenas.
Grassland / savanna
In this food chain, which organism is the secondary consumer?
grass → grasshopper → frog → snake
Frog.
Why:
The grasshopper eats the producer, so it is the primary consumer. The frog eats the grasshopper, so it is the secondary consumer.
In a pond ecosystem, algae, fish, water, rocks, and sunlight are present. Which two are abiotic?
Water, rocks, and sunlight.
Why:
They are non-living parts of the ecosystem.
A tick drinks blood from a deer. The tick benefits, but the deer can be harmed. What relationship is this?
Parasitism.
Why:
One organism benefits while the other is harmed.
A forest is cut down to build houses. Name one biotic factor and one abiotic factor that change.
Answer:
Biotic: trees, birds, insects, mammals.
Abiotic: sunlight, soil temperature, water flow, humidity.
Why:
Removing trees affects both living organisms and non-living conditions.
This ecosystem has freshwater, moving water, fish, insects, frogs, plants along the banks, and animals like otters.
River / freshwater ecosystem
Why does a food chain usually have fewer top predators than producers?
Answer:
Because energy is lost at each level of the food chain.
Why:
Only some energy passes from one trophic level to the next.
A mushroom grows on a dead tree and helps break it down. Is the mushroom biotic or abiotic, and what is its role?
Biotic; it is a decomposer.
Why:
The mushroom is alive and breaks down dead organic matter.
A bird builds a nest in a tree. The bird benefits, but the tree is not helped or harmed. What relationship is this?
Commensalism.
Why:
One organism benefits and the other is not affected.
Climate change causes sea ice to melt. Explain how this affects both an abiotic and biotic part of the Arctic ecosystem.
Abiotic: there is less ice.
Biotic: polar bears may have less hunting habitat, and seals may be affected.
Why:
A change in a non-living factor can affect living organisms.
This ecosystem is where freshwater from rivers mixes with saltwater from the ocean. It often has crabs, birds, young fish, and plants that can survive in salty water.
Answer:
Estuary / brackish water ecosystem
A disease kills many rabbits in an ecosystem. What might happen to the fox population?
Answer:
The fox population may decrease.
Why:
Foxes have less food, so fewer may survive or reproduce.