Charlie is investigating friction. she will use the same amount of force to push two wooden balls across two level surfaces. then she will record her results in the table below. which prediction will most likely describe how friction will affect her findings? the distance for trial 3 will be greater than the distance for trial 1 partly because the weight difference of the balls will affect friction. the distance for trial 2 will be greater than the distance for trial 1 because the difference in surface roughness will affect friction. the distance for trial 4 will be greater than the distance for trial 2 partly because the weight difference of the balls will affect friction. the distance for trial 3 will be greater than the distance for trial 4 because the difference in surface roughness will affect friction.

Which of the following describes a boom period? a. as one population increases, another population decreases. b. as one population increases, the other population also increases. c. as one population decreases, another population increases. d. as one population decreases, another population also decreases

Compare the parts of a cell and the cell as a whole to another common nonliving system (i.e., a car, a city, describe the parts of a cell and their primary function.

Choose the incorrect statement (a) the motor end plate membrane is only capable of generating graded potentials, but it is contiguous with the skeletal muscle sarcolemma, which can generate action potentials. (b) propagation of an action potential through the t-tubules into the sarcoplasmic reticulum triggers the release of ca++ into the cytoplasm of a skeletal muscle fiber. (c) the generation of suprathreshold endplate potentials in multiple muscle fibers could be due to the increased frequency of action potential generation at the axon hillock of a single motor neuron. (d) a greater amount of ach would be found in the presynaptic vesicles of a motor unit that fired several action potentials after exposure to botulinum toxin, than in a motor unit that fired several action potentials after exposure to the venom of the krait snake (which contains α-bungarotoxin).