Answer:
Porifera or Sponges
Explanation:
Porifera is the phylum of the simplest multicellular marine animals. Their body is composed of two cell layers (something like tissues) and mesophyl between them. The body is in direct contact with surrounding water through the large number of pores and channels. What makes Sponges so simple is that their cells are unspecialized and that they don't have nervous, digestive or circulatory systems.
Severe low back pain and bruising along his flank
Answer:
The term "symbiosis" includes a broad range of species interactions but typically refers to three major types: mutualism, commensalism and parasitism. Mutualism is a symbiotic interaction where both or all individuals benefit from the relationship.
Explanation: