Which describes the light-dependent stage of photosynthesis?
(Select all that apply.)
A-Photosynthetic pigments absorb energy from light.
B-Hydrogen ions (H+) are moved against their concentration gradient.
C-Carbon dioxide is incorporated into a preexisting sugar molecule.
D-Water is split, which produces oxygen.

How many variables are altered in a good experiment? a.1 b.0 c.2 d.3

The leopard frog and the pickerel frog are two closely related species. in areas where their ranges overlap, the frogs will remain separate species if they

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).