Keystone Test Keystone Biology: Ecology and Homeostasis 2 — Questions and Answers
Question 1: Which term describes the relationship where one organism benefits and the other is harmed?
- Parasitism (Correct answer)
- Mutualism
- Commensalism
- Competition
Correct answer: Parasitism
Parasitism involves one organism (the parasite) benefiting at the expense of the host.
Question 2: What is the carrying capacity of an ecosystem?
- The maximum population size an environment can support (Correct answer)
- The total number of species in an area
- The amount of rainfall an ecosystem receives
- The number of predators in a habitat
Correct answer: The maximum population size an environment can support
Carrying capacity is the largest population size that an environment can sustainably support given available resources.
Question 3: Which type of symbiosis benefits both organisms involved?
- Mutualism (Correct answer)
- Parasitism
- Commensalism
- Predation
Correct answer: Mutualism
In mutualism, both organisms benefit from the relationship, such as bees pollinating flowers while collecting nectar.
Question 4: What is the primary source of energy for most ecosystems on Earth?
- Sunlight (Correct answer)
- Geothermal energy
- Wind energy
- Chemical energy from minerals
Correct answer: Sunlight
Sunlight is captured by producers through photosynthesis and forms the energy base for most food webs.
Question 5: What happens to a population when birth rate exceeds death rate?
- The population grows (Correct answer)
- The population declines
- The population stays the same
- The population reaches carrying capacity immediately
Correct answer: The population grows
When births outnumber deaths, the net population size increases over time.
Question 6: Which process allows cells to release energy from glucose?
- Cellular respiration (Correct answer)
- Photosynthesis
- Osmosis
- Mitosis
Correct answer: Cellular respiration
Cellular respiration breaks down glucose to produce ATP, the cell's usable form of energy.
Keystone Test Keystone Biology: Ecology and Homeostasis 2
Which term describes the relationship where one organism benefits and the other is harmed?