Pros and cons of genetically modifying the animals people eat? 

Explanation:

   GMOs are food items that have been made using genetic engineering techniques. ...

   GMO foods are easier and less costly for farmers to grow, which makes them cheaper for the consumer. ...

   The main concerns around GMOs involve allergies, cancer, and environmental issues — all of which may affect the consumer.

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.

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.