The Site of the Union of the Upper and Lower

question 25

Multiple Choice

The site of the union of the upper and lower eyelids closest to the nasal region is the

• A) medial commissure
• B) lateral commissure
• C) palpebral fissure
• D) lacrimal caruncle

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Definitions:

Stomata

Microscopic openings on the surfaces of leaves and stems that regulate gas exchange and water vapor between the plant and the atmosphere.

Photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water, producing oxygen as a byproduct.

RuBP Carboxylase

An enzyme that catalyzes the first major step of carbon fixation in the process of photosynthesis, converting ribulose bisphosphate (RuBP) and carbon dioxide into two molecules of 3-phosphoglycerate.

Photorespiration

A process in plant metabolism where the enzyme RuBisCO oxygenates RuBP, leading to a decrease in photosynthetic efficiency and carbon fixation.