Cellular Energy Study Guide

Vocabulary flashcards covering core terms, cellular organelles, and processes from the Cellular Energy Study Guide.

Energy

The capacity or ability to perform work and drive cellular processes.

Autotroph

An organism that synthesizes its own organic nutrients and food, typically using light or chemical energy.

Heterotroph

An organism that cannot produce its own food and must obtain energy by consuming other organisms.

Van Helmont’s experiment

An experiment demonstrating that plant growth and mass accumulation derive primarily from water and air rather than soil nutrients.

Photosynthesis

The process by which autotrophs convert light energy into chemical energy, represented by the equation $6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$.

Reactants of Photosynthesis

The input substances required for photosynthesis: carbon dioxide ($CO_2$), water ($H_2O$), and light energy.

Products of Photosynthesis

The output substances produced by photosynthesis: glucose ($C_6H_{12}O_6$) and oxygen ($O_2$).

ATP

Adenosine triphosphate, the primary energy currency of the cell; it consists of adenine, a ribose sugar, and three phosphate groups, and releases energy when the bond between the second and third phosphate groups breaks.

Chloroplast

The membrane-bound plant cell organelle in which photosynthesis occurs.

Mitochondria

The cellular organelles where cellular respiration occurs to convert biochemical energy from nutrients into ATP.

Stomata

Microscopic openings or pores located primarily on the undersides of leaves that facilitate gas exchange and regulate water transpiration.

Guard Cells

Specialized pairs of cells that frame each stoma and regulate its opening and closing in response to water pressure and environmental conditions.

Cellular Respiration

The metabolic pathway that breaks down glucose in the presence of oxygen to yield carbon dioxide ($CO_2$), water ($H_2O$), and ATP.

Aerobic Respiration

Oxygen-dependent cellular respiration carried out in three main stages: glycolysis, the citric acid cycle (Krebs cycle), and the electron transport chain.

Chemosynthesis

The biological process by which certain organisms use energy released by inorganic chemical reactions to produce food in the absence of sunlight.

Fermentation

An anaerobic cellular process that produces energy without oxygen; the two main types are alcoholic fermentation and lactic acid fermentation.