This structure is unique to cardiac muscle cells, and allows individual cells to be firmly attached to each other (to provide mechanical strength during contraction), and also allow the action potential to spread rapidly through the cardiac muscle tissue, so that contractions are smooth and coordinated. This is:.
a) desmosomes
b) gap junctions
c) intercalated discs
d) Z discs
e) sarcomeres

The terrestrial planets are characterized by having a a.) silicate core b.) iron-rich silicate core c.) iron-rich metallic core d.) none of these

Which of the following is a good strategy when it comes to desserts

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.