LAB QUIZ 4

The hormone that lowers blood glucose levels is ______.

insulin

When insulin is given in excess blood glucose levels ______.

decrease

Excess insulin can lead to a dangerous condition called insulin ______.

shock

A condition of low blood glucose is called ______.

hypoglycemia

A condition of high blood glucose is called ______.

hyperglycemia

Insulin helps move glucose from the blood into body ______.

cells

One major effect of insulin is to ______ blood glucose.

lower

Insulin stimulates glucose uptake in certain tissues by causing ______ transporters to move to the plasma membrane.

GLUT4

GLUT4 transporters are stored in the ______ of the cell until stimulated by insulin.

cytoplasm

Insulin promotes the ______ of GLUT4 transporters to the plasma membrane.

translocation

When GLUT4 transporters are inserted into the plasma membrane glucose can enter the cell more ______.

easily

Early signs of hypoglycemia include ______ and shakiness.

hunger

Severe untreated hypoglycemia may lead to ______ or unconsciousness.

seizures

A person experiencing hypoglycemia may feel weak shaky or very ______.

confused

Fish showing normal glucose levels would display ______ swimming speed.

normal

Fish with hyperglycemia may show ______ swimming or darting.

increased

Fish in insulin shock may appear lethargic and unable to move the ______ fin normally.

dorsal

A ______ potential occurs when ligand-gated channels open and ions move through them.

graded

A resting membrane potential of about -70 mV means the inside of the cell is more ______ than the outside.

negative

Sodium ions tend to diffuse ______ the cell through sodium leakage channels.

into

Potassium ions tend to diffuse ______ of the cell through potassium leakage channels.

out

Leakage channels are normally ______ open.

always

The resting membrane potential is mainly due to ion movement down concentration ______.

gradients

Action potentials are initiated at the ______ hillock.

axon

The axon hillock contains ______-gated channels.

voltage

These channels open when the membrane reaches ______.

threshold

An action potential has two main phases: depolarization and ______.

repolarization

After repolarization there is often a brief period of ______.

hyperpolarization

During depolarization the membrane potential becomes more ______.

positive

During repolarization the membrane potential becomes more ______ again.

negative

Action potentials travel along the ______ of the neuron.

axon

Insulin lowers blood glucose by increasing glucose uptake into ______.

cells

Low blood glucose can affect nervous system function because neurons rely heavily on ______.

glucose

Both membrane potential concepts and glucose regulation are important for normal ______ function.

nervous system