Question

Which of the following statements about automatic behaviors (also called fixed action patterns) is FALSE?

	A.	They are innate.
	B.	They may be triggered by a specific, unlearned stimulus or “releaser”.
	C.	Once activated, they may continue toward completion regardless of sensory feedback.
	D.	Automatic behaviors are rarely, if ever, adaptive.
	E.	Choosing this answer indicates that you believe that all of the above statements are true and that none of them are false.

Which of the following demonstrates saltatory conduction?

	A.	A depolarization causes voltage-gated sodium channels to open, causing an inflow of sodium ions. This leads to further depolarization and further opening of sodium channels.
	B.	Action potentials “jump” from one node of Ranvier to the next.
	C.	Electrical impulses travel through circuits of neurons.
	D.	Sensory neurons take information about a stimulus to the brain where that information is processed. The brain then invokes motor neurons to initiate a response.

Answer 1

The answer to your query is as follows:

Q1. The correct option is E. All theabove statements are true and none of them is false.

The fixed action patterns or automatic behaviors are innate in nature. This means that these type of behaviors are genetically hardwired in an organism. It can be performed easily in response to a cue and it does not require any prior experience.

Fixed action patterns are triggered by a certain sign stimulus or specific releaser. They are independent of experience. They are not learned and thus, it is complete upon the very first release.

Once activated or released, the fixed action pattern or automatic behavior continues to completion regardless of the sensory feedback or even when there are changes in the surrounding environment or if the stimulus is removed.

Q2.The correct answer is B. Action potentials “jump” from one node of Ranvier to the next. Saltatory conduction can be defined as the jumping mechanism in which the electrical impulse skips or jumps from one node of Ranvier to the other node. It travels down the full length of an axon. Thus, it speeds up the arrival of the impulse at the nerve endings. The non-myelinated nerve fibres shows the slower continuous progression of depolarization as compared to the myelinated neurons.

The uninsulated or unmyelinated nodes of Ranvier are the only points in the nerve fibre axon where ions are exchanged across the axonal membrane. Thus, it regenerates the action potential between the insulated myelin regions of the axon.

Hope it helps!