In muscle cells, fermentation produces
a. lactate and nad^+
b. pyruvate
c. lactate, nadh, and atp
d. co2, ethanol, nadh, and atp
e. co2, ethanol, and nad^+

Which best describes how the common cold spreads in the human body? a bacteria burst out of normal cells killing them b viruses replicate inside respiratory cells c bacteria inject dna into normal cells d viruses insert dna into bacteria

Why is the theory of evolution important? it disproves all other theories about how life began. it provides a topic for debate. it is a unifying concept in biology. it explains how life began. i know for sure, it is not "it is a unifying concept in biology."

Juan and carol were studying invertebrates in biology. they knew that segmented or earth worms preferred a dark, moist habitat. during this lab, they would be investigating the responses of organisms called planaria or dugesia tigrina. these were simple flatworms that still had a one-way digestive system and a very simple nervous system. juan and carol placed the planaria in a petri dish containing cool, distilled water that was partially covered with black paper. they shined a light on the dish. next, they removed the paper and placed a small amount of chicken liver at one end of the dish. they added a few large salt crystals to the water. finally, they added drops of hot water to the cool water in the petri dish. their results can be seen in the data table. according to their experiment, all but one conclusion is valid.