Where does heart excitation originate?
a. atrioventricular node
b. intercalated disk
c. sinoatrial node
d. pericardium
e. all cardiac muscle fibers simultaneously
c
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A constitutive mutation in the lac operon may be of several types. Name two types of constitutive mutations
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Macroevolution is _____
A) the same as microevolution, but includes the origin of new species B) evolution above the species level C) defined as the evolution of microscopic organisms into organisms that can be seen with the naked eye D) defined as a change in allele or gene frequency over the course of many generations
A Native American tradition uses a "tea" made by soaking willow bark in water as a pain-reliever. Does it work? Why?
What will be an ideal response?
Members of the genus Clostridium are spore-forming and aerobic.
Answer the following statement true (T) or false (F)