When a Gram positive bacterial culture is too old, it is possible that the Gram stain reaction will not be accurate. This is because the cell wall of an old bacterial cell has become weakened. Therefore, the cell wall becomes “leaky” and is more likely to no longer be able to retain the primary dye during the Gram stain procedure.

When the cell concentrates potassium within, against the natural tendency of matter, it is performing a.passive diffusion b.facilitated diffusion c.active transport d.pinocytosis

Which of the following is true of metabolism in its entirety in all organisms? a) metabolism depends on a constant supply of energy from food. b) metabolism uses all of an organism's resources. c) metabolism consists of all the energy transformation reactions in an organism. d) metabolism manages the increase of entropy in an organism.

When one dna molecule is copied to make two dna molecules, the new dna contains a) 25% of the parent dna. b) 50% of the parent dna. c) 75% of the parent dna. d) 100% of the parent dna. e) none of the parent dna.