I'll answer number 3 for you.
Which are decomposers within a spruce-fir forest ecosystem?
the answer is mushrooms.
Some mushrooms are known for growing over dead things..... I think.
Mutualism, both of the animals benefit from the relationship.
Answer:
The correct answer will be option-D
Explanation:
The aerotaxis movement experiment performed by the Theodor W. Engelmann played an important role in understanding the photosynthesis.
The experiment was performed on the <em>Spirogyra </em>filamentous algae which were exposed to a different wavelength of light.
The other aerobic bacteria present in the test tubes started moving and accumulated near the two regions of the <em>Spirogyra</em> where they were exposed to the blue and red light of the VIBGYOR.
The region receiving red and blue light produced more oxygen through photosynthesis which indicated that these two wavelengths of the light are more active for photosynthesis than any other wavelengths.
Thus, option-D is the correct answer.
The lymphatic system includes areas of high concentrations of APCs, T and B cells.
<h3>What is the lymphatic system?</h3>
The lymphatic system is a branch of the circulatory system which consists of a system of organs , tissues, cells and vessels known as lymphatic vessels, which help transport the fluid, lymph around the body.
The lymphatic system contains high concentration of immune cells.
Therefore, the lymphatic system includes areas of high concentrations of APCs, T and B cells.
Learn more about lymphatic system at: brainly.com/question/3318384
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