AP Biology: Unit 4 Review (CED)

Front

What are the three parts of signal transduction pathway?

Back

reception, transduction, response

Answer explanation

The correct answer is 'reception, transduction, response'. In signal transduction pathways, reception involves detecting a signal, transduction is the process of converting that signal, and response is the cellular action taken.

Front

What is NOT involved with transduction in signal amplification?

Back

ligands

Answer explanation

Ligands are signaling molecules that bind to receptors to initiate a response, but they are not part of the transduction process itself. Secondary messengers, protein modification, and phosphorylation cascades are all involved in amplifying the signal.

Front

Which of the following is NOT a response by the cell from a signal transduction pathway?

Back

All of the above are responses

Answer explanation

All the options listed (cell growth, gene expression, secretion of molecules) are indeed responses from a signal transduction pathway. Therefore, the correct answer is 'all of the above are responses'.

Front

What occurs when the ligand binds to the receptor?

Back

confirmation change in shape of receptor

Answer explanation

When the ligand binds to the receptor, it induces a conformational change in the receptor's shape. This change is crucial for activating the receptor and initiating a cellular response.

Front

Impact of a mutation in any domain of the protein components of the transduction signaling pathway.

Back

Alters response of the cell.

Answer explanation

A mutation in the protein components of the transduction signaling pathway can alter the response of the cell by changing how signals are processed, leading to different cellular outcomes.

Front

Which feedback mechanism involves homeostasis of a particular condition by regulating physiological processes?

Back

Negative Feedback

Answer explanation

Negative feedback is a mechanism that maintains homeostasis by counteracting changes in physiological processes, ensuring stability. In contrast, positive feedback amplifies changes, which does not support homeostasis.

Front

Which feedback mechanism involves amplifying responses and processes in biological organisms?

Back

Positive Feedback

Answer explanation

Positive feedback amplifies responses in biological systems, enhancing processes like childbirth and blood clotting, making it the correct choice. In contrast, negative feedback reduces changes, maintaining homeostasis.

Front

Which of the following is NOT a stage of the cell cycle? interphase, cytokinesis, mitosis, apoptosis

Back

apoptosis

Answer explanation

Apoptosis is not a stage of the cell cycle; it refers to programmed cell death. The cell cycle includes interphase, mitosis, and cytokinesis, which are essential for cell division and growth.

Front

Which stage is where the cell no longer divides? Options: G₀, G₁, G₂, S

Back

G₀

Answer explanation

G0 is the stage where cells exit the cell cycle and enter a quiescent state, meaning they no longer divide. In contrast, G1, G2, and S are all stages of the cell cycle where the cell prepares for or undergoes division.

Front

Order of steps in mitosis?

Back

prophase, metaphase, anaphase, telophase

Answer explanation

Mitosis occurs in a specific order: prophase (chromosomes condense), metaphase (chromosomes align), anaphase (sister chromatids separate), and telophase (nuclear membranes reform). Thus, the correct sequence is prophase, metaphase, anaphase, telophase.