Body Systems
Which body system breaks down food into nutrients your body can use?
The digestive system breaks down food into small molecules your cells can absorb.
What is an ecosystem?
A community of organisms and their environment.
What is a producer?
An organism that makes its own food.
What is a limiting factor?
Something that restricts population size.
What is a trait?
A characteristic an organism has.
What is the main job of blood vessels in the circulatory system?
Blood vessels carry blood throughout the body, delivering oxygen and nutrients and removing waste.
Give an example of an abiotic factor.
Sunlight, water, soil, temperature.
Identify the primary consumer: grass → rabbit → snake → hawk
Rabbit
Give an example of a population increase and cause.
More food → more rabbits
Inherited vs. acquired traits?
Inherited = born with; acquired = learned or gained.
Predict what would happen if the respiratory system stopped exchanging oxygen and carbon dioxide.
Cells would not get oxygen and would not remove carbon dioxide, causing the body to shut down.
What happens if rainfall suddenly decreases in a forest ecosystem?
Plants decrease → herbivores decrease → predators decrease.
Compare decomposers to consumers.
Decomposers break down dead material; consumers eat other organisms.
Disease affects frogs—what happens to insects and snakes?
Insects increase; snakes decrease.
Example of a learned behavior?
Riding a bike.
Explain how the digestive and circulatory systems work together to support the body.
The digestive system absorbs nutrients, and the circulatory system transports those nutrients to cells.
Explain the difference between a terrestrial and aquatic ecosystem.
Terrestrial ecosystems are land-based; aquatic ecosystems are water-based.
Why does energy decrease as you move up a food chain?
Energy is lost as heat at each level.
Why does carrying capacity matter?
It prevents overuse of resources.
What happens if a species stops reproducing?
It becomes extinct.
A student is running during recess. Describe how three body systems work together to help them move.
Muscular system contracts muscles; respiratory system brings in oxygen; circulatory system delivers oxygen to muscles.
A new predator moves in. Explain how this affects multiple populations.
Prey decreases; predator population may grow then stabilize.
Create a 4-organism food chain.
Example: grass → grasshopper → frog → hawk.
Describe a real event that could cause a population crash.
Habitat loss, pollution, overhunting.
Why might tall parents have a short offspring?
Genetic variation / recessive traits.