Energy Transformations Biology exam revision

Flashcards covering key vocabulary related to energy transformations, photosynthesis, and cellular respiration.

Autotrophs

Organisms that convert inorganic matter into organic matter, like CO2 and water, using solar energy; they produce all the organic compounds in ecosystems.

Heterotrophs

Organisms that gain their organic compounds from autotrophs or other heterotrophs; also known as 'consumers'.

Phototroph

Uses energy from the sun to synthesize compounds for nutrition.

Chemotrophs

Obtains energy through chemical processes (chemosynthesis); oxidation of electron donors in the environment

Heterotroph

An organism that cannot manufacture their own food but rather obtain its food and energy by taking in organic substances.

Chloroplast

Organelle found in (most) photosynthetic eukaryotes and used for photosynthesis.

Mitochondrion

Organelle found in (most) eukaryotes, including plant and animal cells, and used for cellular respiration.

Photosynthesis

The process in which light energy is transformed into chemical energy (glucose).

Cellular Respiration

The process in which glucose is broken down and ATP is made.

ATP

An energy-rich compound (adenosine triphosphate) formed in the mitochondria that drives all metabolic processes within cells.

Stomata

Structures responsible for the movement of gases into and out of the plant; located on the outside surface of the leaf.

Thylakoid Membrane

Where the light-dependent reactions of photosynthesis occur.

Stroma

Where the light-independent reactions (Calvin cycle) of photosynthesis occur.

Chlorophylls

Major light-trapping pigments located on the grana membranes.

Light Dependent Stage

The stage of photosynthesis where light energy is absorbed by pigments and converted to chemical energy, producing ATP and NADPH; takes place in the thylakoid membranes.

Light Independent Stage (Calvin Cycle)

The stage of photosynthesis where hydrogen ions and carbon dioxide are combined to produce glucose; occurs in the stroma.

Sucrose and Starch

Polymers of glucose molecules produced in photosynthesis; sucrose is the most easily transported, and starch is the most common storage molecule.

Limiting Factor

The factor present in the smallest amount that limits the rate of photosynthesis.

Mesophyll

Inner tissue of the leaf containing chloroplasts.

Guard Cells

Cells surrounding the stomata that regulate their opening and closing.

Mitochondria

The location of the Krebs cycle and the electron transport chain.

Glycolysis

Process that occurs in the cytoplasm around the mitochondria.

Aerobic Respiration

Glycolysis, Krebs Cycle (citric acid cycle), electron transport chain

Anaerobic Respiration

Alcohol fermentation, lactic acid fermentation

Glycolysis

The stage of aerobic cellular respiration that occurs in the cytoplasm and splits glucose into 2 pyruvate molecules, producing 2 ATP.

Krebs Cycle

The stage of aerobic cellular respiration that occurs in the matrix of the mitochondria and produces electron carriers; pyruvate is converted to Acetyl CoA.

Electron Transport Chain

The stage of aerobic cellular respiration that occurs on the cristae of the mitochondria and uses electron carriers to produce water and ATP.

Alcohol Fermentation

A type of fermentation where the products are CO2 and ethanol (alcohol) and 2 ATP are produced

Lactic Acid Fermentation

A type of fermentation where lactic acid is the end product and 2 ATP molecules are produced