Pleasee help All the subjects in this experiment were exercising for a long period of time. Power lifters and Olympic sprinters complete their entire event in less than 10 seconds. These types of activities do not require oxygen. Which of these best describes the process by which the muscles of these athletes obtain energy without oxygen?

aerobic respiration

anaerobic respiration

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cell specialization

How do accessory pigments chlorophyll?

Read this summary of a scientific theory: "cells are the most basic structural and functional units of life. all living organisms are made up of one or more cells. all cells that are alive in the world today came from pre-existing cells." which of the following would require this theory to be modified? -a.) a survey finds that a majority of people believe viruses carry out the basic processes of life. -b.) a prominent scientist says she feels strongly that one day the theory will be challenged by life on other planets. -c.) the dna of unicellular and multi-cellular organisms is shown to have many fundamental similarities. -d.) scientific observations show that microscopic organisms living in the deep ocean are not made up of cells.

Explain why it’s important for scientists to study the sun. list at least two challenges researchers face when examining earth’s nearest star.