Which kind of muscle fibers contract rapidly?

What behavior of an expectant mother is unhealthy for the fetus

Which of the following is also referred to as "swayback"? a. kyphosis b. scoliosis c. lordosis d. none of the above

Which of the following represents a difference between viruses and viroids? a) viruses infect many types of cells, whereas viroids infect only prokaryotic cells. b) viruses have capsids composed of protein, whereas viroids have no capsids. c) viruses have genomes composed of rna, whereas viroids have genomes composed of dna. d) viruses cannot pass through plasmodesmata, whereas viroids can.