Exam 4: Principles of Neural and Hormonal Communication

The outward movement of sodium ions rapidly restores the negative resting potential.

If a graded potential is large enough,it can initiate an action potential before the graded change dies off.

Endocrine specificity is a result of ____.

In myelinated fiber,impulses "jump" from node to node,skipping over the myelinated sections of the axon in a process called ____________________ conduction.

The most common means by which cells communicate with one another is indirectly through signal molecules.

What type of eicosanoids involve local messengers in inflammatory responses and cause profound airway constriction characteristic of asthma?

Although the cAMP and Ca₂+ pathways are the most prevalent second-messenger systems,some cells use cyclic ____________________.

Voltage-gated channels open or close in response to changes in membrane potential.

____________________ is the study of homeostatic chemical adjustments and other activities accomplished by hormones.

In addition to myelination,what else influences the speed with which an axon can conduct action potentials?​

Nerve and muscle are considered ____________________ tissues because they produce electrical signals when excited.

What is the temporarily depolarized region of a membrane called?

What is the precursor for all steroid hormones?

The resting membrane is ____ more permeable to potassium than to sodium.

Action potentials occur in a(n)____________________ fashion.

Due to its recorded appearance,an action potential often referred to a ____.

Many growth factors that help regulate cell growth and division,such as nerve growth factor and epidermal growth factor,act via the JAK/STAT pathway.

Figure 4-5 Use the accompanying diagram to answer the corresponding questions. -Which number in the figure represents an open or activated voltage-gated sodium channel?

Scientists recently discovered a possible new route for direct exchange of materials between cells: ____.

An unmyelinated fiber has a low density of voltage-gated channels along its entire length.