In Addition to Outgassing by Volcanoes, Another Important Contributor to the Formation

question 32

Multiple Choice

In addition to outgassing by volcanoes, another important contributor to the formation the Earth's oceans and atmosphere was

• A) impacts by icy planetesimals
• B) material directly accreted from the Sun
• C) material directly accreted from the solar nebula
• D) melting and vaporization of polar glaciers

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Definitions:

Mesophylls

The inner tissue of a leaf, containing many chloroplasts, where photosynthesis occurs.

Stroma

Thick, cytoplasm-like fluid between the thylakoid membrane and the two outer membranes of a chloroplast. Site of light-independent reactions of photosynthesis.

Rubiscos

The enzyme involved in the first major step of carbon fixation in the process of photosynthesis, playing a pivotal role in converting carbon dioxide into organic compounds.

Stomata

Singular stoma. Of plants, tiny gaps between pairs of guard cells in epidermis; allow internal tissues to exchange gases with the air. Can be closed to prevent water loss.