Currently, Researchers Believe That Speech Capability Developed in Human Ancestors

question 20

Multiple Choice

Currently, researchers believe that speech capability developed in human ancestors by __________ years ago.

• A) 50,000 to 75,000
• B) 100,000 to 150,000
• C) 200,000 to 250,000
• D) 300,000 to 400,000

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Definitions:

Phloem

The vascular tissue in plants responsible for transporting sugars and other metabolic products downward from the leaves.

Vascular Tissue

The specialized tissue in plants that conducts water and nutrients through the plant body, comprising mainly of xylem and phloem.

Lignin

A substance found in many plant cell walls that confers rigidity and strength, particularly in woody tissues.

Polymer

A large molecule composed of repeating structural units, typically connected by covalent chemical bonds, found in many materials and biological systems.