Why Have Plants Been Implicated in the Ordovician and Devonian

question 16

Multiple Choice

Why have plants been implicated in the Ordovician and Devonian glaciations,but not the Proterozoic glaciations?

• A)Proterozoic plants used anoxygenic photosynthesis.
• B)Proterozoic plants had simple root structures that did not increase rock weathering.
• C)Land plants had not yet evolved during the Proterozoic.
• D)The nonvascular plants present during the Proterozoic did not contribute to global nutrient cycles.

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Definitions:

Optic Chiasm

A structure located at the base of the brain where the optic nerves partially cross, allowing visual information from each eye to be processed by both hemispheres of the brain.

Olfactory Epithelium

A specialized tissue inside the nasal cavity that is responsible for detecting odors through the binding of odor molecule to receptor neurons.

Cochlear Implants

Electronic devices that partially restore hearing by directly stimulating the cochlear nerve in the inner ear.

Hair Cells

Sensory receptors located in the inner ear, responsible for converting sound vibrations into electrical signals that can be interpreted by the brain.