AP Biology Unit 4 Review: Cell Communication & Cycling

Front

What is glucagon and its role in the body?

Back

Glucagon is a hormone produced by the pancreas that promotes the breakdown of glycogen into glucose, increasing blood sugar levels, especially during low energy states.

Front

What triggers the release of glucagon?

Back

Low cellular ATP concentration triggers the release of glucagon, indicating that the body needs more energy.

Front

Define positive feedback in biological systems.

Back

Positive feedback is a process that amplifies a response or increases the output in a system, often leading to a specific outcome, such as the release of more hormones.

Front

Give an example of positive feedback in the human body.

Back

An example of positive feedback is the release of inflammatory cytokines by immune cells, which enhances the immune response.

Front

What is a negative feedback loop?

Back

A negative feedback loop is a control mechanism that counteracts changes in a system, helping to maintain homeostasis.

Front

How do mammals maintain a constant body temperature?

Back

Mammals use negative feedback loops to maintain a constant body temperature, adjusting physiological processes to counteract deviations.

Front

What occurs after metaphase in mitosis?

Back

After metaphase, the next phase in mitosis is anaphase, where sister chromatids are pulled apart to opposite poles of the cell.

Front

What is the significance of anaphase in mitosis?

Back

Anaphase is crucial because it ensures that each daughter cell receives an identical set of chromosomes.

Front

Define mitosis.

Back

Mitosis is the process of cell division that results in two genetically identical daughter cells from a single parent cell.

Front

What are the main phases of mitosis?

Back

The main phases of mitosis are prophase, metaphase, anaphase, and telophase.