Answer:
C
Explanation:
The major histocompatibility complex (MHC) is a group of genes whose function is to codify proteins that participate in the immune response, helping the system to <u>recognize foreign substances to develop an immune response</u>.
<u>Histocompatibility or compatibility of tissue </u>is given by self-identifications molecules (antigens) located on the surface of cells, membrane, these molecules are almost <u>unique to each person</u>, letting the body to distinguish self from non-self.
Answer:
The levels, from smallest to largest, are: molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere.
Explanation:
The planets appeared to move backward in the sky occasionally.
Coral reefs are built by coral polyps as they secrete layers of calcium carbonate beneath their bodies. And inside each coral poly lives single-celled algae called zooxanthellae. So basically in simplistic terms, coral polys create coral reefs and algae is in coral polys which also goes into coral reefs when they are made.