#1: which of the following is true of the electrons in the bohr model of an atom?

a. they exist at specific energy levels.

b. they cannot move from one orbital to another.

c. they are equally close to the nucleus.

d. they give off energy as they jump to a higher level.

Click an item in the list or group of pictures at the bottom of the problem and, holding the button down, drag it into the correct position in the answer box. release your mouse button when the item is place. if you change your mind, drag the item to the trashcan. click the trashcan to clear all your answers. label the following topographic map. click on a label below the map to select it, and then click on the appropriate box on the map to place the label. (increments for contour lines is 50 ft).

16. which of the following accurately describes a step within transcription? a. dna polymerase uses one strand of rna as a template to put together nucleotides. b. the dna strand is used as a template for which a complementary rna strand can be produced. c. the rna strand forms a template by which dna can be built. d. the rna strand is produced within the cytoplasm.

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).