Sodium and potassium ion channels have several negatively charged residues at the entry to the channel. Identify the bases on which K channels specifically select for K ions, in other words, why do K channels not enable Na ions to cross the membrane

Mechanism in attachment.

Explanation:

K⁺ channels have narrow pores, which prevents the passage of larger ions. However, since Na⁺ has an ionic radius smaller than K⁺, this does not explain the selective permeability of these channels towards K⁺.

In this case, the channel pore has a narrow selective filter which is delimited by the backbone carbonyl oxygens (C=O). When a K⁺ ion enters in the selection filter it interacts with these oxygens, and the molecules of water bound to K⁺ are displaced, which allows the passage of the dehydrated ion K⁺ through the pore. However, a dehydrated Na⁺ is too small to interact with these carbonyl oxygens in the selective filter, which stays open. As a consequence, the Na⁺ ion remains bonded to the water molecules in a hydrated complex that is too big to pass through the channel.

false because ozone (o3) depletion does not cause global warming, but both of these environmental problems have a common cause: human activities that release pollutants into the atmosphere altering it.

global warming is caused primarily by putting too much carbon dioxide into the atmosphere when coal, oil, and natural gas are burned to generate electricity or to run our cars.

explanation:

videntify the dna change shown in the diagram and explain how that change can result in the increased genetic diversity often seen among siblings.identify the dna change shown in the diagram and explain how that change can result in the increased genetic diversity often seen among siblings.