Answer:
3. Antibody-independent pathways of complement activation rely on complement components that directly bind to microbial surfaces.
Explanation:
There are three pathways of complement activation:
- The classical pathway.
- The alternative pathway.
- The lectin pathway.
The classical pathway is triggered by binding of C1 either to the pathogen surface or to antibody bound to the pathogen.
The alternative pathway is triggered by the spontaneous hydrolysis of soluble C3 to C3(H₂O) and initiates eventual deposition of C3 convertase on microbial surfaces.
The lectin pathway is triggered by the binding of mannose-binding lectin or ficolins to carbohydrate residues in microbial cell walls and capsules.
1 C. 2. b 3,A 4A hope this helpps
RNA and DNA are both types of nucleus acids. In their names long names, they both have the words “nucleic acid” in them. Nucleic acids are composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus.
The greater the surface area of a cell, the faster the cell can transport materials across its membrane because there is more area to absorb/excrete materials. We also want the surface area much higher than the volume of a cell. the more volume a cell has the slower the transport of diffusion will be. If the cell is smaller because it has a higher surface area than it does volume. Because of this larger SA:V ratio, smaller cells will transport materials faster.
Shleiden and Theodor Schwann were the first to recognize that all plants and animals are composed of cells.
Hope this helped :)
