Unit 4 AP Biology Insta-Review (Cell Communication & Cell Cycle)

Front

What phase is the M checkpoint located in?

Back

Metaphase

Front

What is a signaling molecule called?

Back

Ligand

Front

What binds to turn on or off gene expression?

Back

Transcription factor

Front

What type of feedback is described when ethylene causes fruit to ripen and release more ethylene?

Back

Positive feedback

Front

What type of feedback is most common in biological systems?

Back

Negative feedback

Front

What is the role of a ligand in cell communication?

Back

A ligand is a signaling molecule that binds to a receptor to initiate a response in the target cell.

Front

Define the term 'transcription factor'.

Back

A transcription factor is a protein that binds to specific DNA sequences, controlling the rate of transcription of genetic information.

Front

What is the difference between positive and negative feedback mechanisms?

Back

Positive feedback amplifies a response, while negative feedback reduces or dampens a response.

Front

What is the function of the M checkpoint in the cell cycle?

Back

The M checkpoint ensures that all chromosomes are properly attached to the spindle before proceeding with mitosis.

Front

What is the significance of the G1 phase in the cell cycle?

Back

The G1 phase is where the cell grows and prepares for DNA replication.