if an organism shows the dominant trait, can you tell just by looking at what its genotype is? and why

you cannot tell exactly what it's genotype, but you know it's one of two genotypes.

Explanation:

if the organism has the dominant trait it can either be Bb or BB.

option a is correct i.e.

explanation:

in context to the membrane of nerve impulse, the outer membrane of neuron is semi permeable that is only sodium ions can pass through the membrane i.e. smaller ions can pass through the membrane while larger ions cannot pass through it.

a

explanation:

many plants naturally reproduce this way, but it can also be induced artificially. horticulturalists have developed asexual propagation techniques that use vegetative plant parts to replicate plants. success rates and difficulty of propagation vary greatly. monocotyledons typically lack a vascular cambium and therefore are harder to propagate.