The Cell Cycle — Mitosis, Cytokinesis, and Cancer Explained | Chapter 12 of Campbell Biology

The Cell Cycle — Mitosis, Cytokinesis, and Cancer Explained | Chapter 12 of Campbell Biology

Book cover

Welcome to Last Minute Lecture! This post unpacks the cell cycle—the process by which cells grow, replicate DNA, and divide to produce genetically identical daughter cells—as described in Chapter 12 of Campbell Biology. Learn the steps of mitosis and cytokinesis, cell cycle regulation, and how errors in these processes can lead to cancer. Watch the full video summary below and subscribe for more concise, chapter-by-chapter science learning!

Introduction: Why the Cell Cycle Matters

The cell cycle is fundamental for growth, development, repair, and reproduction. Chapter 12 details how eukaryotic and prokaryotic cells divide, how chromosomes are distributed, and what happens when regulation fails—leading to cancer.

The Cell Cycle and Its Phases

  • Interphase (90% of the cycle):
    • G1 Phase: Cell grows and carries out normal functions.
    • S Phase: DNA is replicated for equal genetic distribution.
    • G2 Phase: Cell grows further and prepares for division.
  • Mitotic (M) Phase:
    • Mitosis: Division of the nucleus and chromosomes.
    • Cytokinesis: Division of the cytoplasm, resulting in two daughter cells.

Mitosis: The Five Stages of Nuclear Division

  • Prophase: Chromatin condenses, spindle forms, nucleolus disappears.
  • Prometaphase: Nuclear envelope dissolves, spindle fibers attach to kinetochores.
  • Metaphase: Chromosomes align at the metaphase plate, spindle fibers connect to kinetochores.
  • Anaphase: Sister chromatids separate, moving to opposite poles.
  • Telophase: Nuclear envelopes reform, chromosomes de-condense.

Cytokinesis: Completing Cell Division

  • Animal Cells: Cleavage furrow pinches the cell into two.
  • Plant Cells: Cell plate forms, becoming a new cell wall between daughter cells.

Binary Fission in Prokaryotes

Prokaryotic cells (bacteria and archaea) divide by binary fission—a simpler process where DNA is replicated, and the cell splits into two. This is considered evolutionarily linked to mitosis in eukaryotes.

Cell Cycle Regulation and Checkpoints

  • G1 Checkpoint: Decides if the cell will divide or enter G0 (a non-dividing state).
  • G2 Checkpoint: Ensures DNA replication is complete before mitosis.
  • M Checkpoint: Ensures chromosomes are attached to the spindle before anaphase.
  • Cyclins & Cdks: Regulatory proteins that drive the cell cycle.
  • MPF (Maturation Promoting Factor): Triggers the cell’s passage from G2 into M phase.

Cancer: Uncontrolled Cell Division

  • Cancer cells ignore cell cycle controls, dividing continuously.
  • They lose density-dependent inhibition and anchorage dependence, allowing tumor formation and spread (metastasis).
  • Benign tumors remain localized; malignant tumors invade tissues and may metastasize.
  • Treatments include surgery, radiation, chemotherapy, and targeted therapies.

Key Terms and Glossary

  • Anaphase: Mitosis stage where chromatids separate.
  • Binary Fission: Prokaryotic asexual reproduction.
  • Cancer: Uncontrolled cell division and tumor growth.
  • Cell Cycle: Sequence of events in a cell’s life.
  • Checkpoints: Regulatory control points in the cell cycle.
  • Cyclin: Regulatory protein controlling cell cycle.
  • Cytokinesis: Cytoplasm division after mitosis.
  • G0 Phase: Non-dividing, resting phase.
  • Metaphase Plate: Imaginary cell center where chromosomes align.
  • Mitotic Spindle: Structure that moves chromosomes during mitosis.
  • MPF: Protein complex triggering mitosis.
  • Telophase: Final mitosis stage with nuclear envelope reformation.

Conclusion: The Cell Cycle’s Central Role in Life

Chapter 12 of Campbell Biology reveals how tightly regulated cell division is essential for growth, repair, and genetic continuity—and how failures in regulation can cause cancer. For a detailed breakdown, watch our full video summary and subscribe to Last Minute Lecture for more clear, science-focused chapter guides.

If this summary clarified the cell cycle and mitosis, watch the video above and subscribe to our channel for ongoing biology support and more chapter breakdowns.

If you found this breakdown helpful, be sure to subscribe to Last Minute Lecture for more chapter-by-chapter textbook summaries and academic study guides.

Comments

Post a Comment

Popular posts from this blog

Behavior Therapies & Evidence-Based Practice — Chapter 9 Summary from Systems of Psychotherapy

Image
Behavior Therapies & Evidence-Based Practice — Chapter 9 Summary from Systems of Psychotherapy Chapter 9 of Systems of Psychotherapy: A Transtheoretical Analysis explores the robust field of behavior therapies, which focus on changing maladaptive behaviors through practical, empirical methods. These approaches, grounded in learning theory and continuous assessment, have become foundational in treating a range of psychological conditions. This expanded summary, based on our podcast-style breakdown of Chapter 9 , highlights the key techniques, theoretical foundations, and clinical applications of behavior therapy. Want a concise video guide? Watch the chapter summary above and subscribe to Last Minute Lecture for more psychology study resources! The Foundations of Behavior Therapy Behavior therapy focuses on observable, measurable changes in behavior rather than probing unconscious processes. Using empirical methods, therapists continuously assess and adjust treatmen...
Read more

Cognitive & Rational-Emotive Therapies — Chapter 10 Summary from Systems of Psychotherapy

Image
Cognitive & Rational-Emotive Therapies — Chapter 10 Summary from Systems of Psychotherapy Chapter 10 of Systems of Psychotherapy: A Transtheoretical Analysis explores the evolution and techniques of Cognitive Therapy (CT) and Rational-Emotive Behavior Therapy (REBT). Developed by Aaron Beck and Albert Ellis, these therapies target the root of emotional distress by challenging and changing maladaptive thought patterns. This in-depth summary, based on our podcast breakdown of Chapter 10 , explains the major concepts, therapeutic techniques, and clinical impact of these cognitive-based approaches. Watch the chapter summary above and subscribe to Last Minute Lecture for expert textbook guides and psychology study resources! The Foundations of Cognitive Therapy & REBT Cognitive therapies emerged in response to limitations of psychoanalysis and behaviorism, emphasizing the role of thoughts in shaping emotions and behaviors. Aaron Beck’s Cognitive Therapy and Albert E...
Read more

Materials Failure: Fracture, Fatigue, and Creep — Chapter 8 Summary from Callister’s Materials Science and Engineering

Image
Materials Failure: Fracture, Fatigue, and Creep — Chapter 8 Summary from Callister’s Materials Science and Engineering Chapter 8 of Materials Science and Engineering: An Introduction by William D. Callister, Jr. and David G. Rethwisch explores the primary failure modes in engineering materials: fracture, fatigue, and creep. This chapter is essential for anyone interested in the reliability, durability, and safety of materials used in engineering structures and components. By understanding these mechanisms, engineers can design safer, longer-lasting products and infrastructure. Watch the full podcast-style summary below, and subscribe to Last Minute Lecture for more clear, chapter-by-chapter breakdowns of foundational STEM topics! Fracture: Ductile vs. Brittle Failure Ductile fracture involves significant plastic deformation and energy absorption prior to failure. It usually provides visual warning signs, making it the preferred mode in most engineering applications. I...
Read more