Explanation:
Psi packaging Element is a cis-acting RNA element identified in the genomes of the retroviruses Human immunodeficiency virus (HIV) and Simian immunodeficiency virus (SIV) It is involved in regulating encapsidation of the retroviral RNA, an essential step in replication.
Sponges are a type of aquatic animal whose body is covered in tiny pores called ostia. The ostia allow water, oxygen, and other nutrients to flow into the sponge's body, and for waste products like ammonia and carbon dioxide to exit their body. The respiratory system of a sponge is based on the process of diffusion.
Answer:
Explanation:
Growth and Maintenance.
Acts as a Messenger. ...
Provides Structure. ...
Maintains Proper pH. ...
Balances Fluids. ...
Transports and Stores Nutrients.
