History of the Earth's Atmosphere, Photosynthesis, and Cellular Respiration

Comprehensive review flashcards covering Earth's cycles, energy pyramids, photosynthesis, and cellular respiration.

Photosynthesis

A biological process performed by plants and phytoplankton that captures sunlight and converts water ($\text{H}_2\text{O}$) and carbon dioxide ($\text{CO}_2$) into chemical energy in the form of glucose ($\text{C}_6\text{H}_{12}\text{O}_6$) and oxygen ($\text{O}_2$).

Chemosynthesis

A process carried out by bacteria living at the bottom of the ocean that uses inorganic chemicals to produce energy, serving as the base of deep-sea food chains without sunlight.

Transpiration

The biological process in the water cycle where moisture is carried through plants and released into the atmosphere as water vapor ($\text{H}_2\text{O}\text{ gas}$).

Evaporation

The physical and chemical process where liquid water from bodies such as the ocean transforms into atmospheric water gas ($\text{H}_2\text{O}\text{ gas}$).

Runoff

Precipitation that moves across the land surface rather than soaking into the soil, eventually flowing into bodies of water like oceans or streams.

Groundwater

Water that penetrates deep into the soil and rock layers of the geosphere, beneath the surface of the Earth.

Photosynthesis Chemical Equation

The balanced chemical formula representing the synthesis of sugar: $6\text{CO}_2 + 6\text{H}_2\text{O} + \text{Light} \rightarrow 6\text{O}_2 + \text{C}_6\text{H}_{12}\text{O}_6$.

Reactants of Photosynthesis

The input substances required for photosynthesis: carbon dioxide ($\text{CO}_2$), water ($\text{H}_2\text{O}$), and light energy.

Products of Photosynthesis

The output molecules produced by photosynthesis: oxygen ($\text{O}_2$) and glucose ($\text{C}_6\text{H}_{12}\text{O}_6$).

Ten Percent Rule ($10\%$)

The ecological principle stating that as energy moves upward through trophic levels of an energy pyramid, organisms only maintain about $10\%$ of the available energy from the level below.

Primary Producers

Autotrophic organisms (such as plants and phytoplankton) positioned at the bottom level (#$4$) of an energy pyramid that capture solar energy and possess the greatest amount of biomass.

Third-Level Consumers

Apex organisms (predators) located at the highest trophic level (#$1$) of an energy pyramid, representing the level with the least amount of biomass.

Decomposers

Organisms such as bacteria and fungi that break down dead biological matter and return/recycle essential nutrients to the soil.

Limiting Factor

An ecological factor (such as eagles preying on snakes) that restricts population size and prevents a population from overgrowing out of control.

Thylakoids

Membrane-bound compartments within the chloroplast where the light-dependent reactions of photosynthesis take place using light and $\text{H}_2\text{O}$ to produce $\text{O}_2$, ATP, and NADPH.

Stroma

The fluid-filled interior space of a chloroplast surrounding the thylakoids where the light-independent reactions (Calvin cycle) synthesize glucose from $\text{CO}_2$.

Light-Dependent Reactions

The initial reactions of photosynthesis occurring in the thylakoid membranes that capture light energy and split water ($\text{H}_2\text{O}$) to produce oxygen ($\text{O}_2$) and generate ATP and NADPH.

Light-Independent Reactions

The phase of photosynthesis taking place in the stroma that uses carbon dioxide ($\text{CO}_2$) from the atmosphere along with ATP and NADPH from the light-dependent stage to synthesize sugars.

Cellular Respiration Chemical Equation

The metabolic process that breaks down food: $\text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2 \rightarrow 6\text{CO}_2 + 6\text{H}_2\text{O} + \text{ATP}$.

Glycolysis

The first step of cellular respiration occurring in the cytoplasm; it breaks down glucose using ATP into $2$ pyruvate molecules, producing NADH and a net output of $2\text{ ATP}$.

Krebs Cycle

The second stage of cellular respiration occurring in the mitochondria; it breaks down pyruvate to release $\text{CO}_2$ and create high-energy electron carriers (NADH and $\text{FADH}_2$) along with ATP.

Electron Transport Chain (ETC)

The final stage of aerobic respiration taking place in the mitochondria; it uses high-energy electrons from NADH and $\text{FADH}_2$ and oxygen ($\text{O}_2$) to generate the majority of cellular energy, yielding approximately $32$ to $34\text{ ATP}$.

Aerobic Respiration

Cellular respiration requiring oxygen ($\text{O}_2$) that takes place within the mitochondria and produces a high total yield of $36\text{ ATP}$.

Anaerobic Respiration

Cellular respiration that occurs in the cytoplasm without oxygen ($\text{O}_2$), producing far less energy with an overall yield of only $2\text{ ATP}$.