All organic compounds contain

Although all organic compounds contain carbon, and almost all have hydrogen, most of them contain other elements as well. The most common other elements in organic compounds are oxygen, nitrogen, sulfur, and the halogens.

Explanation: hope this helps

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

read more on -

d. in sexual reproduction, offspring have more chromosomes than

either parent.

asexual reproduction results in offspring which are genetically the same as the parent organism (not counting a rare mutation). sexual reproduction produces a random mixture of the genetics derived from both parents

explanation: