Keystone Biology: Ecology and Homeostasis Flashcards
6 cards from real Keystone Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Keystone Biology: Ecology and Homeostasis flashcards as text
What is the term for the geographic area where an organism lives?
Answer: Habitat
A habitat is the specific environment where an organism lives and finds food, shelter, and mates.
Which hormone helps regulate blood glucose levels by lowering them?
Answer: Insulin
Insulin is released by the pancreas when blood glucose is high, signaling cells to absorb and use glucose.
What is primary succession?
Answer: Ecological change beginning in an area with no prior life
Primary succession occurs on bare rock or newly exposed land with no existing soil or organisms.
Which of the following is an example of an abiotic factor in an ecosystem?
Answer: Temperature
Abiotic factors are non-living components of an ecosystem, such as temperature, water, light, and soil.
What is biodiversity?
Answer: The variety of living organisms in an area
Biodiversity refers to the variety of species, genetic variation, and ecosystems in a given area.
Which process in the nitrogen cycle converts nitrogen gas from the atmosphere into a usable form for plants?
Answer: Nitrogen fixation
Nitrogen fixation is performed by certain bacteria that convert atmospheric N₂ into ammonia (NH₃) that plants can absorb.
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