a) There are three distinct phases shown in the diagram (A, B, C). Describe what is happening to the population in each phase. b) What population growth model does the population appear to follow? c) What appears to be the carrying capacity of the yeast in the container?

Testing Biological Control Biological control agents are used to battle red imported fire ants. Researchers have enlisted the help of Thelohania solenopsae, a natural enemy of the ants. This microsporidian (Section 23.4) is a parasite that infects ants and shrinks the ovaries of the colony's egg-producing female (the queen). As a result, a colony dwindles in numbers. Are these biological controls useful against imported fire ants? To find out, USDA scientists treated infested areas with either traditional pesticides or pesticides plus biological controls (both flies and the parasite). The scientists left some plots untreated as controls. FIGURE 45.16 shows the results. FIGURE 45.16 A comparison of two methods of controlling red imported fire ants. The graph shows the numbers of red imported fire ants over a 28-month period. Orange triangles represent untreated control plots. Green circles are plots treated with pesticides alone. Black squares are plots treated with pesticide and biological control agents (parasitoid flies and a microsporidian parasite). How did population size in the two types of treated plots change during this same interval?

Testing Biological Control Biological control agents are used to battle red imported fire ants. Researchers have enlisted the help of Thelohania solenopsae, a natural enemy of the ants. This microsporidian (Section 23.4) is a parasite that infects ants and shrinks the ovaries of the colony's egg-producing female (the queen). As a result, a colony dwindles in numbers. Are these biological controls useful against imported fire ants? To find out, USDA scientists treated infested areas with either traditional pesticides or pesticides plus biological controls (both flies and the parasite). The scientists left some plots untreated as controls. FIGURE 45.16 shows the results. FIGURE 45.16 A comparison of two methods of controlling red imported fire ants. The graph shows the numbers of red imported fire ants over a 28-month period. Orange triangles represent untreated control plots. Green circles are plots treated with pesticides alone. Black squares are plots treated with pesticide and biological control agents (parasitoid flies and a microsporidian parasite). If this study had ended after the first year, would you conclude that biological controls had a major effect?

Which parasitic protist evades the host immune system by altering its surface proteins with each generation? a. Paramecium caudatum b. Trypanosoma brucci c. Plasmodium falciparum d. Phytophthora infrstans

The group Diplomonadida is characterized by: a. a mouthlike gullet and hairlike surface. Paramecium is anexample. b. flagella and a lack of mitochondria. Giardia is an example. c. nonmotility, parasitism, and sporelike infective stages. Toxoplasma is an example. d. switching between autotrophic and heterotrophic lifestyles. Euglena is an example. e. large protein deposits and movement by two flagella, which are part of an undulating membrane. Trypanosoma is an example.

Conjugation between two Paramecia produces total daughter cells. 2 4 8 16

Protists with the capabilities to absorb nutrients from dead organisms are called ______. a. photoautotrophs b. autotrophs c. saprobes d. heterotrophs

Testing Biological Control Ant-decapitating phorid flies are just one of the biological control agents used to battle imported fire ants. Researchers have also enlisted the help of Thelohania solenopsae, another natural enemy of the ants. This microsporidian (Section 23.4) is a parasite that infects ants and shrinks the ovaries of the colony's egg-producing female (the queen). As a result, a colony dwindles in numbers and eventually dies out. Are these biological controls useful against imported fire ants? To find out, USDA scientists treated infested areas with either traditional pesticides or pesticides plus biological controls (both flies and the parasite). The scientists left some plots untreated as controls. FIGURE 45.28 shows the results. FIGURE 45.28 A comparison of two methods of controlling red imported fire ants. The graph shows numbers of imported fire ants over a 28-month period Orange triangles represent untreated control plots. Green circles are plots treated with pesticides alone Black squares are plots treated with pesticide and biological control agents (phorid flies along with a microsporidian parasite). 3. If this study had ended after the first year, would you conclude that biological controls had a major effect?

A _______ is the smallest unit that can live and reproduce by itself using energy, raw materials, and DNA instructions.

Which of the following is associated with multiple reproductive episodes during a species’ lifetime? semiparity iteroparity semelparity fecundity