In testing a hypothesis thatʺterritorial defense in European robins is a fixed action pattern that isreleased by the sight of orange feathers,ʺresearchers found that robins defended their territory byattacking anything that was of similar size and had an orange patch. What experiment would youperform next to determine that the color initiated the defense response?A) Repeat the experiment by removing the patch completely. B) Repeat the experiment using a blue patch instead of an orange patch. C) Repeat the experiment by using a model of a robin that was twice the size of a normal robinbut with a small orange patch. D) Repeat the experiment by using a model of a robin that had an orange patch that was twicethe size of a normal patch.

The correct answer is option A) "Repeat the experiment by removing the patch completely".

Explanation:

In this example, researchers believe that European robins have a territorial defense pattern where they attack anything similar to orange feathers, including an orange patch. In order to establish if the color initiated defense response is real it is necessary to repeat the experiment by removing the patch completely. If the European robins do not longer attack, then the researchers can conclude that the color initiated defense response is real.

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.