Which essential chemical must be “fixed” by soil-dwelling bacteria before it can enter the food chain? a. Carbon b. Nitrogen c. Phosphorous d. Both a. and b.

Organisms that can make their own food using inorganic molecules are called: autotrophs heterotrophs photoautotrophs chemoautotrophs

What two products result from photosynthesis? a. water and carbon dioxide b. water and oxygen c. glucose and oxygen d. glucose and carbon dioxide

Plants produce oxygen when they photosynthesize. Where does the oxygen come from? a. splitting water molecules b. ATP synthesis c. the electron transport chain d. chlorophyll

Why are drinking water supplies still a major concern for many countries?

The map below shows the availability of direct solar energy in North America. Some areas are good candidates for solar heating systems and use of solar cells to produce electricity (see legend). What is the potential for using more solar energy where you live?

The movement of mineral nutrients through organisms and their environment is called a __________cycle. biological bioaccumulation biogeochemical biochemical

Which term describes the process whereby toxic substances increase along trophic levels of an ecosystem? a. biomassification b. biomagnification c. bioentropy d. heterotrophy

Figure 22.19 Which of the following statements about the nitrogen cycle is false? Nitrogen fixing bacteria exist on the root nodules of legumes and in the soil. Denitrifying bacteria convert nitrates (NO3 ) into nitrogen gas (N2). Ammonification is the process by which ammonium ion (NH4+) is released from decomposing organic compounds. Nitrification is the process by which nitrites (NO2-) are converted to ammonium ion (NH4+).

Which statement about thylakoids in eukaryotes is not correct? a. Thylakoids are assembled into stacks. b. Thylakoids exist as a maze of folded membranes. c. The space surrounding thylakoids is called stroma. d. Thylakoids contain chlorophyll.