Which organelles aid in their digestion process

This is the main structural axis of the plant that supports leaves, flowers and fruits; transports fluids; stores nutrients and produces new tissue.

Which genetic disorders, caused by an extra x chromosome (xxy), is characterized by a lack of testicular development in males, effeminate features, possible mental impairment, and a thin stature?

In general, characteristics that an organism survive and reproduce become more common in a population over time. what mechanism of evolution cause this change?