Use the Following Information to Answer the Following Questions

question 21

Multiple Choice

Use the following information to answer the following questions.
Malaria is an infectious disease caused by a unicellular eukaryotic organism belonging to the genus Plasmodium.These eukaryotic organisms are transmitted from one person to another by the female Anopheles mosquito when it feeds on human blood.Within humans,the Plasmodium species destroy red blood cells and,without effective treatment,serious infections can lead to death.Currently,more than 400 million people are afflicted with malaria and between 1 and 3 million people die from it each year.Historically,a chemical compound called quinine has been used in developing effective drugs against malaria.In its natural environment,quinine is produced by certain trees native to South America.This chemical is synthesized in the outer layer of tree trunks and acts as an herbivore deterrent.
-Humans,mosquitoes,and Plasmodium together would be considered a(n) ________.

• A)population
• B)community
• C)ecosystem
• D)population and community

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Definitions:

Extinction

In psychology, this refers to the slow reduction and eventual vanishing of a learned reaction when the previously associated conditioned stimulus is not combined with the unconditioned stimulus anymore.

Classical Conditioning

The process of learning by linking a naturally occurring stimulus with one introduced externally.

Conditioned Stimulus

A stimulus that initially has no effect but, when associated with an unconditioned stimulus, eventually triggers a conditioned response.

Fear of Snakes

An intense, irrational fear of snakes, also known as ophidiophobia.