In humans, abo blood types refer to glycoproteins in the membranes of red blood cells. there are three alleles for this autosomal gene: ia, ib, and i. the ia allele codes for the a glycoprotein, the ib allele codes for the b glycoprotein, and the i allele doesn't code for any membrane glycoprotein. ia and ib are codominant, and i is recessive to both ia and ib. people with type a blood have the genotypes iaia or iai, people with type b blood are ibib or ibi, people with type ab blood are iaib, and people with type o blood are ii. if a woman with type ab blood marries a man with type o blood, which of the following blood types could their children possibly have?
a. a and b
b. ab and o
c. a, b, and o
d. a, b, ab, and o

A. A and B.

Explanation: The woman's genotype is IAIB and the man's genotype is ii. Their children inherite the IA allele or IB allele (Dominants) from their mother and only the i allele (recessive) from their father, so these children will have blood type A (genotype IAi) or B type (Genotype IBi).

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.  

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answer: b: experiments that showed that all cells are similar in how they metabolize and in their composition

explanation: