Cell Biology: Cell Communication

·         Question 1

2 out of 2 points

	You have recently identified a molecule that you believe to be a ligand associated with a signal transduction mechanism. All you know about this ligand is that chemically it is hydrophilic. As a result, you expect it to interact with its receptor Answer
	Selected Answer: at the outer cell surface.

·         Question 2

2 out of 2 points

	Hydrophobic messengers include which of the following? Answer
	Selected Answer: retinoids

·         Question 3

2 out of 2 points

	MAPKs are activated by Answer
	Selected Answer: mitogens.

·         Question 4

2 out of 2 points

	Which of the following statements is false with regard to G-protein coupled receptors (GPCRs)? Answer
	Selected Answer: Phosphodiesterase creates cAMP molecules.

·         Question 6

2 out of 2 points

	Synthetic compounds that inhibit receptors by preventing the natural messenger from binding are known as Answer
	Selected Answer: antagonists.

·         Question 7

2 out of 2 points

	IP3 receptors are associated with Answer
	Selected Answer: ER membranes.

·         Question 8

2 out of 2 points

	Kinases are enzymes that Answer
	Selected Answer: add phosphate groups.

·         Question 1

2 out of 2 points

	Hydrophobic messengers include which of the following? Answer
	Selected Answer: retinoids

·         Question 2

2 out of 2 points

	Which of the following statements concerning the properties of ligands for intracellular receptor systems is correct? Answer
	Selected Answer: choices A, B, and C

·         Question 3

2 out of 2 points

	MAPKs are activated by Answer
	Selected Answer: mitogens.

·         Question 4

2 out of 2 points

	Phosphatases are enzymes that Answer
	Selected Answer: remove phosphate groups.

·         Question 5

2 out of 2 points

	All of the following are second messengers, except Answer
	Selected Answer: epinephrine.

·         Question 6

2 out of 2 points

	Which of the following is not a receptor tyrosine kinase? Answer
	Selected Answer: FGF

·         Question 8

2 out of 2 points

	Kinases are enzymes that Answer
	Selected Answer: add phosphate groups.

·         Question 1

2 out of 2 points

	IL-2 is a growth factor that acts on Answer
	Selected Answer: T lymphocytes.

·         Question 6

2 out of 2 points

	Kinases and phosphatases are essential in the cell because they Answer
	Selected Answer: help turn proteins "on and off" through changes in phosphorylation status.

·         Question 8

2 out of 2 points

	IP3 receptors are associated with Answer
	Selected Answer: ER membranes.

·         Question 1

2 out of 2 points

	The glial cells associated with phagocytosis to fight infection and remove debris are the Answer
	Selected Answer: microglia.

·         Question 2

2 out of 2 points

	Of all of the ions associated with generating the resting membrane potential, the permeability of the membrane to ________ is the most important. Answer
	Selected Answer: potassium ions

·         Question 3

2 out of 2 points

	The maximum membrane potential that an ion gradient can produce is the Answer
	Selected Answer: equilibrium potential.

·         Question 5

2 out of 2 points

	The axon branches of a typical neuron terminate at structures called Answer
	Selected Answer: boutons.

·         Question 6

2 out of 2 points

	The phase at the end of an action potential when the membrane potential becomes more negative than it is at rest is the ________ phase. Answer
	Selected Answer: hyperpolarizing

·         Question 7

2 out of 2 points

	The resting potential of a particular nerve cell is -66 mV. Depolarization of the membrane will shift the membrane potential toward Answer
	Selected Answer: 0 mV.

·         Question 8

2 out of 2 points

	All of the following are glial cells except Answer
	Selected Answer: interneurons.

·         Question 5

2 out of 2 points

	The technique that allows one to record ion currents passing through individual channels is known as Answer
	Selected Answer: patch-clamping.

·         Question 5

2 out of 2 points

	An action potential can always be initiated specifically at which of the following locations associated with a neuron? Answer
	Selected Answer: nodes of Ranvier

·         Question 8

2 out of 2 points

	Which of the following statements about action potentials is false? Answer
	Selected Answer: Electrical signals are propagated along a dendrite.

·         Question 2

2 out of 2 points

	Under times of great stress or shock, which of the following neurotransmitters interferes with the perception of pain? Answer
	Selected Answer: enkaphalins

·         Question 4

2 out of 2 points

	Which neurotransmitter is NOT an amino acid derivative? Answer
	Selected Answer: acetylcholine

·         Question 5

2 out of 2 points

	You are examining a recently captured organism from another planet and are currently trying to deduce the types of neurotransmitters associated with the propagation of nerve impulses. You discover a very interesting neurotransmitter and find that, in spite of being alien, it is a derivative of the amino acid tyrosine. As a result, this novel neurotransmitter has to be classified as a(n) Answer
	Selected Answer: catecholamine.

·         Question 6

2 out of 2 points

	Multiple sclerosis is a result of Answer
	Selected Answer: an immune system attack on nerve fibers.

·         Question 7

2 out of 2 points

	Which equation best describes the relationship between ion gradient and equilibrium potential for that ion? Answer
	Selected Answer: Nernst

·         Question 8

2 out of 2 points

	Catecholamines are synthesized by the Answer
	Selected Answer: adrenal gland.

·         Question 7

2 out of 2 points

	Catecholamines are synthesized by the Answer
	Selected Answer: adrenal gland.

·         Question 8

2 out of 2 points

	The somatic nervous system controls Answer
	Selected Answer: skeletal muscles.

·         Question 3

2 out of 2 points

	Under times of great stress or shock, which of the following neurotransmitters interferes with the perception of pain? Answer
	Selected Answer: enkaphalins

·         Question 7

2 out of 2 points

	The somatic nervous system controls Answer
	Selected Answer: skeletal muscles.

·           Question 4

2 out of 2 points

	You stimulate a neuron response by adding a given amount of excitatory neurotransmitter mixed with a 6x higher concentration of an inhibitory neurotransmitter to the synaptic cleft. You expect that Answer
	Selected Answer: as a result of neuronal integration, there will be an inhibitory signal.

·         Question 5

2 out of 2 points

	Which of the following is a disease specifically caused by an autoimmune response against acetylcholine receptors? Answer
	Selected Answer: myasthenia gravis

·         Question 6

2 out of 2 points

	Which of the following drugs interferes with the reuptake of neurotransmitters in order to have its desired clinical effect? Answer
	Selected Answer: Valium

·         Question 3

2 out of 2 points

	All of the following are glial cells except Answer
	Selected Answer: interneurons.

·         Question 4

2 out of 2 points

	Which of the following statements about action potentials is false? Answer
	Selected Answer: Electrical signals are propagated along a dendrite.

·         Question 6

2 out of 2 points

	The somatic nervous system controls Answer
	Selected Answer: skeletal muscles.

·         Question 8

2 out of 2 points

	Which neurotransmitter is NOT an amino acid derivative? Answer
	Selected Answer: acetylcholine

_______________-

·         Question 2

2 out of 2 points

	Kinases and phosphatases are essential in the cell because they Answer
	Selected Answer: help turn proteins "on and off" through changes in phosphorylation status.

·         Question 7

2 out of 2 points

	Desensitization of a cell to a ligand may involve all of the following except Answer
	Selected Answer: destruction of the ligand.

·         Question 8

2 out of 2 points

	IP3 receptors are associated with Answer
	Selected Answer: ER membranes

·         Question 1

2 out of 2 points

	With regard to hormones, responses occurring over the shortest distance would be classified as Answer
	Selected Answer: autocrine.

·         Question 2

2 out of 2 points

	Which of the following is not a receptor tyrosine kinase? Answer
	Selected Answer: FGF

·         Question 3

2 out of 2 points

	Kinases are enzymes that Answer
	Selected Answer: add phosphate groups.

·         Question 4

2 out of 2 points

	Kinases and phosphatases are essential in the cell because they Answer
	Selected Answer: help turn proteins "on and off" through changes in phosphorylation status.

·         Question 5

2 out of 2 points

	To have a hormone receptor system that is responsive to changes in hormone concentration, it is useful if the concentration of the hormone is Answer
	Selected Answer: far below the Kd before the stimulation of hormone secretion.

·         Question 6

2 out of 2 points

	All of the following are second messengers, except Answer
	Selected Answer: epinephrine.

·         Question 7

2 out of 2 points

	IL-2 is a growth factor that acts on Answer
	Selected Answer: T lymphocytes.

·         Question 8

2 out of 2 points

	MAPKs are activated by Answer
	Selected Answer: mitogens.

·         Question 1

0 out of 2 points

	The stimulus for secretion of neurotransmitters into the synaptic cleft is an increase in Answer CALCIUM LEVELS

o    Exposure to sarin, a potent nerve gas, results in muscle paralysis. Therefore, sarin must interfere with which neurotransmitter?
Answer
Selected Answer: dopamine

·         Question 8

2 out of 2 points

	An example of an inhibitory neurotransmitter is Answer
	Selected Answer: GABA.