Transport Across Cell Membranes and Intracellular Compartments and Protein Transport

Cell Biology Chapter 12 and 15 (Essential Cell Biology 5th Edition Book)

Which of the following statements about GABA receptors is not true?

They promote neuronal uptake of Na+.

Which of following statements is false.

The differences in permeability between artificial lipid bilayers and cell membranes arise from variations in phospholipid content.

Which of the following gated ion channels are involved in inhibitory synaptic signaling?

glycine-gated Cl– channels

K⁺ leak channelsare found in the plasma membrane. These channels open and close in anunregulated, random fashion. What do they accomplish in a resting cell?

They keep the electrochemical gradient for K+ at zero.

The stimulation of a motor neuron ultimately results in the release of a neurotransmitter at the synapse between the neuron and a muscle cell. What type of neurotransmitter is used at these neuromuscular junctions?

acetylcholine

Movement of water across a semi-permeable membrane from a hypotonic solution to a hypertonic solution is ____________. 

Osmosis

Which of the following statements does not accurately describe the events involved in the propagation of an action potential?

The opening of transmitter-gated K+ channels helps to repolarize the membrane.

Which of the following is required for the secretion of neurotransmitters in response to an action potential?

voltage-gated Ca2+ channels

Which of the following statements is true?

The nuclear membrane is thought to have arisen from the plasma membrane invaginating around the DNA.

Which of the following choices reflects the correct order of cellular locations through which a protein destined for the plasma membrane travels?

ER —> Cis Golgi —> Trans Golgi—> plasma membrane

Most proteins destined to enter the endoplasmic reticulum _________.

start synthesis on a cytoplasmic ribosomes, but begin to cross the ER membrane while still being synthesized.

A large protein that passes through the nuclear pore must have an appropriate _________.

sorting sequence, which typically contains the positively charged amino acids lysine and arginine.

Your friend works in a biotechnology company and has discovered a drug that blocks the ability of Ran to exchange GDP for GTP. What is the most likely effect of this drug on nuclear transport?

Nuclear transport receptors would be unable to release their cargo in the nucleus.

Signal sequences that direct proteins to the correct compartment are _________.

encoded in the amino acid sequence and sufficient for targeting a protein to its correct destination.