4 is true with question you asked
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.
B, element
a molecule would require more than one atom. if one atom is left and is still gold, it would not be a molecule/mixture/compound.
Answer:
In animals, oxygen combines with food in the cells to produce energy for daily activity and then gives off carbon. The carbon combines with oxygen to form carbon dioxide (CO2) and is released back into the atmosphere as a waste product when animals breathe and exhale.
Channel protein is a membrane protein that spans the phospholipidbilayer (a strongly non-polar environment).
