Answer:
The region of retina devoid of photoreceptor cells (rod cells and cone cells)
Explanation:
The retina is the layer of the eyeball and is packed with rod cells and cone cells responsible for night and day vision respectively. The blind spot is the region in the retina where no rod cells and cone cells are present.
Absence of these photoreceptor cells ensures that no vision is formed in this part of the retina. However, the blind spot serves as the site from where the optic nerve passes through the retina and serves to transmit the impulse to the brain.
Cephalization refers to the concentration of nerve cells and sensory organs at the anterior (head) end of the body.
Adaptations are what organisms do in order for them to survive and adapt to the environments that Mother Nature is presenting them.
1. Crocodiles - have tough and scaled skin that allows them to camouflage and catch prey in the water
2. Frogs - have developed bodily fluids that secrete poison to prevent predators from attacking them
3. Bats - have developed their echolocation to help them in hunting for food at night time.
4. Coelachants - have maintained their extra fins for sensory motor in the water
5. Lampreys - have maintained their tooth-funnel like mouths in order to feed on their hosts.
Answer:
Neuron would be unable to receive signal from environment and previous neuron.
Explanation:
A neuron cell comprises of dendrites, cell body and axon. Dendrites are the projections of neuron cells that receive the electrochemical signal from other neurons and transfer them to soma (body) of a neuron cell. While axon transfer it to next neuron from cell body.
So if the mutation cause loss of dendrites of neuron cells it would be unable to receive the signal from the previous neuron and environment because receptors to receive signals are present on dendrites. Consequently the cell would loss the communication with other cell and that cell may dies and it can also cause paralysis of that particular area because of loss of communication.