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Parasitism Definition

Parasitism benefits one organism at another's expense, causing harm. For example, ticks feed on hosts like humans without giving benefits.

View Lesson on Symbiosis (Interactions Between Organisms)
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Symbiosis (Interactions Between Organisms)

Fun Facts

  • Leeches suck blood from hosts like birds and reptiles.
  • Green-banded broodsacs take over snail brains to attract birds.
  • Mistletoe extracts water and nutrients from trees, sometimes killing them.

Why Do We Need To Know About Parasitism

Learning about how some living things live off others helps us understand how everything in nature is connected and why it’s important to keep these connections healthy. This is useful for doctors, vets, and scientists who study animals and plants, especially the ones that cause problems like ticks and leeches.

It’s also important for people who work with forests and farms to know about things like mistletoe that can harm plants. Plus, experts who work on keeping oceans and lands healthy need to understand these relationships to help protect all kinds of life. Knowing about these parasitic relationships helps lots of different jobs and keeps our environment healthy.

Frequently Asked Questions

What are different types of symbiosis?
Competition, predation, parasitism, mutualism, and commensalism
How is predation essential to maintaining an ecosystem?
Without predators, organisms that are prey (like the rabbit in the video) would become overpopulated in an ecosystem. Eventually, they would eat all of the plants, become sickly, and/or die of starvation.
What do food webs show about an ecosystem?
Food webs show where each organism gets its energy from.
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