Lon channels are not continuously open and are highly selective.
(a) true
(b) false

True

Explanation: Ion channels are very specific and are voltage gated channels. They are highly specific and selective for particular ions only.

Example: Some of the channels allow the flow of potassium ions but do not allow sodium ions to cross the membrane to maintain the concentration.

Some of the positive ion channels allow only the movement of positive ions and no negative ions. These channels are not always open and opens only when there is a concentration gradient.