Name the organ where protein digestion begins

True or false. mucous membranes secrete mucus that traps pathogens.

Which of the following supports the argument that viruses are nonliving? a) they are not cellular. b) their dna does not encode proteins. c) they have rna rather than dna. d) they do not evolve.

Why do rna viruses appear to have higher rates of mutation? a) rna nucleotides are more unstable than dna nucleotides. b) replication of their genomes does not involve proofreading. c) rna viruses can incorporate a variety of nonstandard bases. d) rna viruses are more sensitive to mutagens.