that's all wrong the real answer is b.99.3
Answer:
A person who receives a gene for sickle cell disease from one parent and a normal gene from the other has a condition called "sickle cell trait." Sickle cell trait produces no symptoms or problems for most people. Sickle cell disease can neither be contracted nor passed on to another person.
A bilayer of phospholipids.
Answer:
Our immune system produces antibodies against that antigen of pathogen.
Explanation:
Injecting an antigen from a pathogen would help our immune system memorize the infection and protect our body from causing of the disease because our immune system produces antibodies against that antigen so when the pathogen enters our body these antibodies attack on that and prevent them of causing infection in the body so that's why injecting an antigen has to be done from the childhood to prevent diseases.
<span>A planulae is not one of the three major structures of coral reefs as it is one of the stages in the life cycle of a jellyfish known as the free swimming larvae stage.
Coral reef structures are made up of fringing reefs that grow directly from the shore,
atoll reefs that grow upward usually in a lagoon, and barrier reefs are separated from the land and shore by open water.</span>
