Exam 2: Cell Physiology

Which of these statements is correct for ATP synthase?

If a typical body cell is placed in a 5 percent saline solution, what will happen to the cell?

Which of the following occurs when chemically gated Na⁺ channels open?

An unmyelinated fibre with a large diameter can conduct action potentials more rapidly than an unmyelinated fibre with a smaller diameter.

Under an electron microscope, the plasma membrane appears as a trilaminar structure consisting of two dark layers separated by a light middle layer.

Which of these statements correctly describes what happens when "temporal summation" takes place?

Movement of K⁺ into the cell requires energy expenditure, whereas movement of Na⁺ into the cell does not.

An action potential in a presynaptic neuron induces opening of voltage-gated ____________________ channels in the synaptic knob, which triggers exocytosis of synaptic vesicles.

Which of the following is known to be second messengers?

Match the terms, labelled a. through d., to their descriptions. (Options may be used more than once or not at all.) a.microtubules b.microfilaments c.intermediate filaments d.micro trabecular lattice -play(s) a key role in muscle contraction

Which of the following statements correct describes IPSP?

In active transport, a substance moves from an area of ____________________ concentration to an area of ____________________ concentration.

Match the terms, labelled a. through f., to their correct descriptions. (Options may be used more than once or not at all.) a.plasma membrane b.nucleus c.cytoplasm d.cytosol e.organelles f.cytoskeleton -highly organized membrane-bound intracellular structures

If presynaptic neuron Z is repeatedly stimulated very rapidly, what change would you expect to occur in the postsynaptic neuron?

Assume a hypothetical postsynaptic neuron has three presynaptic inputs, X, Y, and Z. When presynaptic neurons X and Y are stimulated simultaneously, the postsynaptic neuron reaches threshold and undergoes an action potential; yet, when presynaptic neurons X and Z are stimulated simultaneously, there is no change in potential of the postsynaptic neuron. Which of these statements correctly describes the presynaptic neurons Y and Z?

At the end of repolarization, the newly opened channels for ____________________ ions close.

Presynaptic facilitation results from which of the following?

With secondary active transport, the movement of __________________.

Which of the following applies to lysosomes?

The extracellular matrix and the local cells that secrete it are collectively known as connective tissue.