One of the first diagnostic tools used at the hospital was an electrocardiogram (EKG or ECG), which reflects the electrical activity of the cardiac muscle. We know that the atria contract first (the P wave) and then, after a brief delay, the ventricles contract (the QRS complex). Given that the heart does not have any nerves to stimulate the cardiac muscle cells, how is the timing of contraction coordinated? How do action potentials get from muscle cell to muscle cell? If the EKG shows a long delay between the P wave and the QRS complex, which type of cardiac tissue might have been damaged?

Ameadow ecosystem includes many species of grasses and small shrubs, several herbivores, and a few carnivores. a fungus colonizes the meadow and kills most of its vegetation. what is most likely to happen to the populations of herbivores and carnivores in the ecosystem? a. the populations of herbivores and carnivores will increase because there will be less competition for chemical energy. b. the populations of herbivores and carnivores will remain stable because the fungus cannot infect these organisms. c. the populations of herbivores will decrease because of vegetation loss, but the population of carnivores will remain stable. d. the populations of herbivores and carnivores will decline because less chemical energy will be stored in the ecosystem.

Scenario 5 1) take 10 red and 10 black beans and place them, mixed, on the table. record the starting phenotype # and frequencies (% of your total population) of your starting population in the table provided (generation 0). 2) act as a predator. “capture” as many organisms as you can until you have reduced the population to three organisms. put them aside. at this point, the predators die. 3) the remaining organisms each produce 2 clonal offspring. multiply your organisms accordingly and allow them to mix on the table. calculate and record the resultant phenotype # and frequencies (% of your total population) of your population in the table provided (generation 1). 4) repeat the reproduction event, allowing each of your organisms to produce 2 clonal offspring. calculate and record the resultant phenotype # and frequencies (% of your total population) of your population in the table provided (generation 2). 5) repeat the reproduction event, allowing each of your organisms to produce 2 clonal offspring. calculate and record the resultant phenotype # and frequencies (% of your total population) of your population in the table provided (generation 3).

When in solution, a molecule that moves slowly across an artificial membrane moves rapidly across a plasma membrane. this molecule rapidly enters the cell regardless of whether its concentration is higher inside or outside the cell. using this information, which transport mechanism is most likely to be responsible for the movement of the molecule across a plasma membrane? view available hint(s)when in solution, a molecule that moves slowly across an artificial membrane moves rapidly across a plasma membrane. this molecule rapidly enters the cell regardless of whether its concentration is higher inside or outside the cell. using this information, which transport mechanism is most likely to be responsible for the movement of the molecule across a plasma membrane? active transportexocytosis