A Bird Sitting on the Limb of a Tree Is

question 45

Multiple Choice

A bird sitting on the limb of a tree is moving about 30 km/s with respect to the Sun. If the bird takes 1 second to drop down to a worm below, the worm would be 30 km downrange from the bird when it reached the ground. This faulty reasoning is best countered with Newton's

• A)law of inertia.
• B)law of gravity.
• C)laws of motion.
• D)none of the above

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Definitions:

PGA

An acronym that can refer to several concepts; in a biological context, it often stands for phosphoglyceric acid, a 3-carbon molecule formed in the Calvin cycle of photosynthesis.

PGAL

Phosphoglyceraldehyde, an intermediate molecule formed in the photosynthesis and glycolysis metabolic pathways, important in the metabolic process.

NADPH

Nicotinamide adenine dinucleotide phosphate, a coenzyme involved in cellular processes, mainly anabolism and as a reducing agent in anabolic reactions.