Photosynthesis - Lesson 1: Energy and Life

Vocabulary flashcards covering energy concepts, metabolic pathways, autotrophy versus heterotrophy, ATP synthesis, and the fundamentals of photosynthesis.

Energy

The ability to do work or cause change.

Catabolic Pathway

A metabolic process in which large molecules are broken down into small ones, releasing energy and harvesting the chemical potential energy found in organic molecules.

Anabolic Pathway

A metabolic process in which small molecules are assembled into large ones, requiring an input of energy.

Autotrophs

Organisms that "automatically" make their own food by producing energy from inorganic compounds and fixing it into organic compounds for later use.

Photoautotrophs

Organisms such as plants, algae, and some protists and bacteria that convert the sun's energy into sugar through photosynthesis.

Chemoautotrophs

Bacteria that use inorganic compounds (chemicals) to fix energy.

Heterotrophs

Organisms that obtain energy by consuming organic compounds produced by autotrophs to convert into ATP, with all consumed energy originally originating from the sun.

ATP (Adenosine Triphosphate)

The basic energy source for all cells, composed of adenine, ribose, and $3$ phosphates, which stores and releases chemical energy for cellular functions.

ADP (Adenosine Diphosphate)

A molecule that functions like a partially charged battery, consisting of adenosine and two phosphate groups, which becomes ATP when an inorganic phosphate ($\text{P}_i$) and energy are added.

Mitochondrial ATP Yield

The production of ATP occurring in the mitochondria that yields $32$ to $38$ ATP per molecule of glucose from existing ADP and inorganic phosphate ($\text{P}_i$).

Photosynthesis

The process of converting light energy into chemical energy, taking place inside the chloroplasts.

Photosynthesis Equation

$6\text{CO}_2 + 6\text{H}_2\text{O} \xrightarrow{\text{Light}} \text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2$ (Carbon Dioxide + Water in the presence of Light yields Glucose + Oxygen).

Oxygen Source in Photosynthesis

The oxygen ($\text{O}_2$) released during photosynthesis is produced directly from the splitting of water ($\text{H}_2\text{O}$).

Glucose Carbon and Oxygen Origin

The carbon and oxygen atoms found in glucose ($\text{C}_6\text{H}_{12}\text{O}_6$) originate from carbon dioxide ($\text{CO}_2$).

Light Reaction

The photosynthetic stage that takes advantage of excited electrons and photosynthetic pigments such as chlorophyll.

Chlorophyll a

A photosynthetic pigment that is blue-green in color, absorbs violet and red light best, and reflects blue and green light.

Chlorophyll b

A photosynthetic pigment that is yellow-green in color, absorbs blue and orange light best, and reflects yellow and green light.