They do not have a distinct head and thorax but a fused version of the two called a cephalothorax. That's one of the major differences between insects and crustaceans, both being subgroups of arthropods.
Answer:
Codominance
Explanation:
Codominance is when two dominant traits are equally dominant, and therefore they both are expressed in the offspring's phenotype. For example, if in a flower, blue (BB) and red (RR) are codominant their offspring would be both red and blue. One of the common examples of codominance in humans is blood type, which is seen in AB blood since A and B are equally dominant.
Rods and cones are similar in that they both release glutamate as the primary neurotransmitter. During signalling the rod and cone photoreceptors signal their absorption of photons via a decrease in the release of the neurotransmitter glutamate to bipolar cells at its axon terminal. Every rod and cone photoreceptor release the same neurotransmitter, glutamate.