6.1 An Overview of Metabolism

Question 1

adenosine triphosphate (ATP)

Answer 1

the molecule that provides energy in a form that all cells can readily use to perform the work of the cell. ATP is the universal energy currency for all cells.

Question 2

organisms can be classified according to:

Answer 2

their energy and carbon sources

Question 3

how can organisms harvest energy from their environment?

Answer 3

they can obtain energy from the sun or from chemical compounds

Question 4

phototroph (THINK ENERGY)

Answer 4

an organism that captures energy from sunlight-plants use sunlight to convert carbon dioxide and water into sugar and oxygen, sugar contains energy in their chemical bonds that can be used to synthesize ATP

Question 5

chemotroph (THINK ENERGY)

Answer 5

an organism that derives its energy directly from organic molecules such as glucose-broken down with oxygen to produce carbon dioxide and water, energy in chemical bonds converted to energy carried in the bonds of ATP

Question 6

autotroph / “self feeders” (THINK CARBON)

Answer 6

any organism that is able to convert carbon dioxide into glucose, thus providing its own organic source of carbon

Question 7

heterotroph / “other feeders” (THINK CARBON)

Answer 7

an organism that obtains its carbon from organic molecules synthesized by other organisms

Question 8

photoheterotrophs

Answer 8

microorganisms that gain energy from sunlight but obtain their carbon from preformed organic molecules

Question 9

chemoautotroph

Answer 9

microorganisms that extract energy from inorganic sources but build their own organic molecules

Question 10

metabolism

Answer 10

the chemical reactions occurring within cells that convert molecules into other molecules and transfer energy in living organisms

Question 11

what are the two branches that divide metabolism?

Answer 11

catabolism and anabolism

Question 12

catabolism

Answer 12

the set of chemical reactions that break down molecules into smaller units and in the process, produce ATP (ex. breakdown of carbohydrates into sugar, can be broken down further to release the energy in their chemical bonds)

Question 13

anabolism

Answer 13

the set of chemical reactions that build molecules from smaller units and require an input of energy, usually in the form of ATP (ex. synthesis of macromolecules such as carbohydrates)

Question 14

the energy harvested as ATP during the breakdown of molecules in catabolism can be used to:

Answer 14

synthesize molecules in anabolism