Question

which two of the following are functions performed by archaeal pili?
promoting dna transfer between cells
protecting against heat denaturation
facilitating chemotaxis
adhesion to human cells
adhesion to surfaces

Explanation:

Archaeal pili have specific functions. Promoting DNA transfer between cells (via mechanisms like conjugation - related pili functions in prokaryotes, and archaea can use pili for genetic exchange) and adhesion to surfaces (pili help archaea attach to environmental surfaces, like biofilm formation or surface colonization) are known functions. Protecting against heat denaturation is not a pili function (heat resistance is from other cellular components like chaperonins or membrane lipids). Facilitating chemotaxis is done by flagella or chemosensory systems, not pili. Adhesion to human cells is not a typical archaeal pili function as archaea are not usually human pathogens with such adhesion, unlike some bacteria. So the two correct functions are promoting DNA transfer between cells and adhesion to surfaces.

Answer:

• promoting DNA transfer between cells
• adhesion to surfaces