A Photon with a Frequency of 2

question 7

Multiple Choice

A photon with a frequency of 2.1 × 10⁴ s ^{− 1} has an energy of:

• A) 6.2 × 10¹² J
• B) 5.1 × 10¹¹ J
• C) 1.4 × 10 ^{− 29} J
• D) 1.9 × 10 ^{− 19} J

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Definitions:

Pericycle

A layer of cells found just inside the endodermis of plant roots, important for initiating lateral root growth.

Cortex

The outer layer of an organ or structure, such as the brain’s cortex involved in many higher-level brain functions, or the cortex of plants responsible for storage and transport.

Pericycle

A layer of cells in plant roots that can give rise to lateral roots and is involved in secondary growth.

Endodermis

The innermost layer of cells in the cortex of a plant root, functioning as a selective barrier that regulates the passage of substances from the soil into the vascular system.