3. What are structures C and D in Figure 13–1, and what is their significance?

Some birds look for food near cattle and other livestock. the movement of the cattle churns up the ground, making insects available to the birds. the cattle appear to be unaffected by the presence of the birds. what kind of relationship exists between the birds and the cattle? o a. parasitism o b. commensalism o c. predation o d. mutualism

Which of the following describes a difference when gram-positive bacteria are compared to gram-negative bacteria?

Black fur(b) in guinea pigs is dominant over white fur(b). find the probability of a homozygous offspring in a cross: bb x bb. a. 0% b. 25% c. 50% d. 75% e. 100%