Cellular Respiration and Energy Notes

Vocabulary flashcards covering cellular respiration, caloric measurements, energy storage, and the initial stage of glycolysis.

Source of Organismal Energy

Organisms obtain the energy they need from food.

calorie (lowercase "c")

The amount of energy needed to raise the temperature of $1\text{ gram}$ of water by $1^\circ\text{C}$.

Calorie (capital "C")

A dietary Calorie used on food labels that is equal to $1\text{ kilocalorie}$, or $1{,}000\text{ calories}$.

Heat Energy of Glucose

$1\text{ gram}$ of the sugar glucose releases $3{,}811\text{ calories}$ of heat energy.

Heat Energy of Beef Fat

$1\text{ gram}$ of the fat found in beef releases $8{,}893\text{ calories}$ of heat energy.

Gradual Energy Capture

The method by which cells break down food molecules gradually to capture energy in chemical bonds, rather than burning food and releasing all energy immediately as heat.

Cellular Respiration

A process of energy conversion that releases energy from food in the presence of oxygen.

Balanced Chemical Formula for Cellular Respiration

$$6O_2 + C_6H_{12}O_6 \rightarrow 6CO_2 + 6H_2O + \text{Energy}$$

Word Equation for Cellular Respiration

$$\text{Oxygen} + \text{Glucose} \rightarrow \text{Carbon dioxide} + \text{Water} + \text{Energy}$$

Consequence of Single-Step Energy Release

Releasing all energy from glucose at once would cause most of it to be lost in the form of light and heat.

Three Main Stages of Cellular Respiration

Glycolysis, the Krebs cycle, and the electron transport chain.

Glycolysis

The first chemical pathway of cellular respiration that glucose enters.

ATP Energy Yield of Glycolysis

Approximately $10\%$ of the available energy from glucose is captured to produce ATP during this initial stage.

Pyruvic Acid Chemical Bonds

The location where the remaining $90\%$ of glucose's energy is still locked at the end of glycolysis.