1.1 How Organisms Obtain Energy? U2M8L1 — Vocabulary Flashcards

Vocabulary flashcards covering key energy- and metabolism-related concepts from the notes, including autotrophs/heterotrophs, metabolism, catabolic/anabolic pathways, ATP/ADP, and photosynthesis/cellular respiration.

Energy flow through an ecosystem

The pathway of energy movement from the Sun to autotrophs (producers) to heterotrophs (consumers) and ultimately to the environment, illustrating how energy is transferred and transformed but not recycled.

Autotroph

An organism that can synthesize its own food from inorganic substances, serving as the base of the food chain.

Chemoautotroph

An autotroph that obtains energy by oxidizing inorganic substances (e.g., hydrogen sulfide) rather than by using light.

Photoautotroph

An autotroph that uses light energy to convert carbon dioxide and water into organic matter (e.g., plants).

Heterotroph

An organism that cannot synthesize its own food and must obtain energy by ingesting other organisms or organic compounds.

Producer

An autotroph at the base of the food chain that creates organic matter from inorganic substances, usually via photosynthesis.

Primary consumer

An organism that feeds on producers (typically herbivores).

Secondary consumer

An organism that feeds on primary consumers (often carnivores or omnivores).

Decomposer

An organism that breaks down dead matter and waste, returning nutrients to the environment.

Metabolism

The sum of all chemical reactions in a living organism, enabling processes like growth, energy production, and waste elimination.

Catabolic pathway

Metabolic pathways that break down large molecules into smaller ones, releasing energy.

Anabolic pathway

Metabolic pathways that build large molecules from smaller ones, requiring energy input.

ATP (adenosine triphosphate)

The primary energy-carrying molecule in cells, a nucleotide consisting of adenine, ribose, and three phosphate groups.

ADP (adenosine diphosphate)

A nucleotide formed when ATP loses a phosphate group; can be recharged to ATP by adding a phosphate group.

ATP cycle

The continuous cycle of ATP being hydrolyzed to ADP + Pi to release energy, and ADP + Pi being re-synthesized to ATP to store energy for cellular work.

Photosynthesis

the process by which photoautotrophs convert light energy into chemical energy (glucose) using carbon dioxide and water.

Cellular respiration

The process by which cells convert chemical energy from nutrients into ATP, typically via glycolysis, the Krebs cycle, and the electron transport chain.