Karen measures the initial volume of water as 12.5 mL. She then adds a 2.3 gram rubber stopper and the volume rises to 20.8 mL. What is the volume of Karen's rubber stopper?

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).

How do the sperm cells get from the stigma to the ovules?

The cellular plasma membrane is selectively permeable, which means some materials move through it while others cannot. the movement of materials into and out of the cell is called membrane transport. this activity will you identify the different mechanisms of membrane transport