Which of the following best describes the most reasonable prediction of how soil composition might change with depth? A. Weathered rock will only be found in the topmost layer of soil, with no rock material at greater depths.

B. Soil will contain more organic material nearer the surface and less organic material farther down.

C. Most of the plant and animal material in the soil will be found at a greater depth.

D. The weathered rock near the surface will be composed of larger fragments, with smaller fragments farther down.

The tubes transporting minerals and water upward are called ?

How is transcription similar to translation in terms of base pairing?

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).