Which Term Best Describes the Movement of Ions and Large

question 69

Multiple Choice

Which term best describes the movement of ions and large molecules across membranes via transport proteins against their concentration gradient?

• A) passive diffusion
• B) a symport
• C) facilitated diffusion
• D) active transport

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Definitions:

SRY Gene

Located on the Y chromosome in males, this gene codes for a transcription factor that binds to regulatory DNA. At about 5 weeks gestation, it turns on genes that start the production of other proteins responsible for the development of gonads into testes.

Zygotes

The initial cell formed when a new organism is conceived, created by the fusion of sperm and egg cells.

XY Chromosome

The combination of chromosomes characterized as male in humans, where a Y chromosome inherited from the father pairs with an X chromosome from the mother.