Highly potent toxins that are excreted by microorganisms, such as bacteria, and can cause damage to the host by destroying cells or even disrupting the normal cellular metabolism are called:
a) exotoxins.
b) endotoxins.
c) mutations.
d) enterotoxins.

4. multiple crosses were made between true-breeding lines of black and yellow labrador retrievers. all the f1 progeny were black. when these progeny were intercrossed, they produced an f2 consisting of 91 black, 39 yellow and 30 chocolate. a. propose an explanation for the inheritance of coat color in labradors. b. propose a biochemical pathway for coat color determination and indicate how the relevant genes control coat coloration.