An antibiotic inhibits the formation of cross-links between the molecules that form cell walls in bacteria. Which statements explain why bacteria are killed by the antibiotic? 1 The bacterial cell is destroyed by osmotic lysis. 2 Cellulose molecules cannot form hydrogen bonds. 3 The cell wall is no longer partially permeable.

Which statement about tuberculosis (TB) is not correct?

More cases of malaria are being reported in Europe. Other diseases, formerly confined to tropical countries and trans…

Which statement is an example of epidemiological evidence linking smoking to lung cancer?

What occurs in the sieve tube elements of a photosynthesising leaf and an actively growing root?

Some soil-borne fungi cause wilting in crop plants by growing within the xylem vessels. Which process will be directl…

Two species of animal are found in the same area of forest and grassland. In the spring and summer they eat the same …