Antigens are proteins that are found on the surface of the pathogen and are viruses, fungi, or bacteria. Nonliving substances such as toxins, chemicals, drugs, and foreign particles. Antigens are usually carried by proteins and polysaccharides, and less frequently, lipids but it also needs to be attached to a large carrier molecule which is usually a protein. When an antigen enters the body, the immune system produces antibodies against it. The Antigen stimulates the immune system to produce antibodies. YOUR WELCOME ;)
The best answer to the question 'What are the nonliving components of the environment that shape an ecosystem?' would be letter d. Abiotic factors are those components of the environment that are non-living or does not have life. All the other choices have life.
Osmosis of Water Across the Membrane. Osmosis is the tendency for water molecules to move from where there is a higher concentration to where there is a lower one. ... The cell membrane helps to regulate and slow down the flow of water into the cell. This is yet another way that the cell membrane helps maintain homeostasis