Organization and Communication + Homeostasis Quiz

The blue-shaded area in the figure above represents the

ECF

Plasma

ISF

Total body water

ICF

ISF

In the regulation of plasma glucose concentration, insulin acts as the

Effector.

Input.

Integrating center.

 Output.

 Sensor.

Output

The tip of the dashed arrow is on

A secretory cell.

A receptor.

A target cell.

A chemical messenger.

A gap junction.

A gap junction

Neurohormones are released by

Endocrine cells.

Exocrine cells.

Neurons.

Neurosecretory cells.

Neurosecretory cells

If a cell has a membrane potential of +5 mV, then which of the following would be true?

The ICF has excess positive charge, and the ECF has excess negative charge.

The ECF has excess positive charge and the ICF has excess negative charge.

Both the ICF and ECF have excess negative charge.

Both the ICF and ECF have excess positive charge.

The ICF has excess positive charge, and the ECF has excess negative charge.

If a cell's resting potential were -60 mV, which of the following would be a depolarization?

A change in membrane potential from -60 mV to -70 mV

A change in membrane potential from -70 mV to -60 mV

A change in membrane potential from -60 mV to +0 mV

A change in membrane potential from +10 mV to -60 mV

A change in membrane potential from -60 mV to +0 mV

Which of the following is a characteristic of action potentials?

They can vary in strength.

They are always depolarizations.

They weaken as they spread from their point of origin.

They have a long duration.

They are always depolarizations.

A neuron has a resting potential of -80 mV and a threshold of -60 mV. Which of the following depolarizing stimuli would induce an action potential, if the axon hillock were at the resting potential?

A stimulus of either +20 mV or +30 mV.

Only a stimulus of +30 mV.

Only a stimulus of +20 mV.

Stimuli of either +10 mV, +20 mV, or +30 mV.

A stimulus of either +20 mV or +30 mV.

Which of the following is true for chemical synapses, but not for electrical synapses?

The synapse does not include a synaptic cleft.

The presynaptic neuron does not induce graded potentials in the postsynaptic neuron.

Two neurons are connected by gap junctions.

The presynaptic neuron releases neurotransmitters.

The presynaptic neuron releases neurotransmitters.

Which of the following would result in the exocytosis of synaptic vesicles?

Opening of sodium ion channels

Closing of calcium ion channels

Closing of sodium ion channels

Opening of calcium ion channels

Opening of calcium ion channels

Maintenance of relatively constant conditions within the internal environment

What is Homeostasis?

A condition that is maintained by homeostasis

What is a regulated variable? 

False

A regulated variable is maintained within relatively broad limits?

Set Point

What is the optimal value in homeostasis called? 

True

Homeostasis is maintained through negative feedback mechanisms

The difference between the actual value and the set point

What is the error signal in homeostasis?

When the actual value of the regulated variable deviates from the set point

When does negative feedback occur?

sensor, effector, integrating center

The three parts of the negative feedback mechanism

Sensor -> Integrating Center -> Effector

What is the order of the negative feedback mechanism?

True

Blood Glucose Concentration is a regulated variable maintained by a negative feedback mechanism.