PLEASE HELP ME When a neurotransmitter (ligand) binds to the ligand-gated ion channel of a postsynaptic neuron, the shape of the channel protein , allowing ions to flow the cell. These ions are messengers that perpetuate the signal transduction of the nerve signal.

In familial hypercholesterolemia individuals homozygous for the allele causing the disorder completely lack receptors on liver cells that take up cholesterol from the blood stream. heterozygous have one-half the number of receptors while individuals homozygous for the normal allele are phenotypically normal. this is an example of a. epistasis b. complete dominance c. incomplete dominance d. codominance

Match the examples to the correct level of organization. 1. system level roses, snakes, puppies 2. organism level roots, stamens, leaves 3. tissue level bone, cartilage, blood 4. organ level heart, veins, arteries

Cold case files recently began re-investigating an old murder case. the murder took place in the park; a young man, james, was hit over the head with a brick and killed. police suspected the jealous former boyfriend of james' wife, karen. whoever killed james may have washed their hands in a near-by bird bath as detectives found blood in the bird bath. since the murder took place before dna fingerprinting was available, the suspected killer, ronnie, went free. detectives are now reviewing the blood evidence using dna fingerprinting. based on the dna fingerprints of all possible suspects, who is james' killer?