While we are sleeping, we can still perceive sounds and touch. this means that our bodies keep parts of the subdivision of the nervous system active during sleep?

Somatic nervous

Peripheral

Explanation:

The nervous system can be divided into two subdivisions:

The Central nervous system (CNS) is formed by the brain and spinal cord while the Peripheral nervous system (PNS) connects the CNS to all the other parts of the body. The PNS is the one who carry messages from the organs and senses to the CNS. So, when we're sleeping this peripheral nervous system is active and carrying messages from our organs and senses (like ear and touch) through our body.

The PNS has two subdivisions:

The first one is in charge on sensory and motor information to and from the CNS. The second one is in charge of our internal glands and organs.

The sentence of the problem mentions that when we are sleeping we can still perceive sounds and touch. The Somatic Nervous system is the one in charge of sensory information (sounds and touch) .

Therefore: While we are sleeping, we can still perceive sounds and touch. this means that our bodies keep parts of the somatic nervous subdivision of the peripheral nervous system active during sleep.

organisms that lack symmetry are called asymmetrical and belong to phylum porifera/sponges.

organisms with specialized stinging cells belong to phylum cnidaria. stinging cells are called cnidoblast cells.

cnidarians show two morphological forms : polyp (sessile) and medusa (mobile)

filter feeding is observed in porifera members.  

alternation of generation is observed in coelenterata or cnidaria. there is alternation of asexual polyp form and sexual medusoid form. it is also referred as metagenesis.

option c is the correct answer.