Cell growth

Definition

Cell growth refers to the process by which a cell increases in size and mass, preparing for division and contributing to the overall growth of an organism. This process is critical as it involves the synthesis of new cellular components, enabling cells to replicate accurately during the cell cycle. Cell growth is tightly regulated and occurs during specific phases of the cycle, particularly during interphase when the cell prepares for mitosis.

5 Must Know Facts For Your Next Test

1. Cell growth is primarily influenced by various external factors such as nutrients, growth factors, and environmental conditions.
2. During interphase, especially in the G1 phase, cells focus on increasing their size and synthesizing proteins necessary for DNA replication.
3. Once cells reach a certain size and have duplicated their DNA, they will enter the S phase where DNA synthesis occurs.
4. The regulation of cell growth is crucial because uncontrolled growth can lead to conditions such as cancer.
5. Cell growth must be carefully coordinated with cell division to ensure that each daughter cell receives the correct amount of cellular components.

Review Questions

• How does cell growth during interphase prepare a cell for division?
  • During interphase, particularly in the G1 phase, a cell undergoes significant growth by synthesizing proteins and duplicating organelles. This preparation ensures that when the cell enters mitosis, it has all the necessary components to divide successfully into two functional daughter cells. Proper growth during interphase is crucial because it sets the stage for accurate DNA replication in the S phase and ensures that each new cell will function correctly after division.
• Discuss the role of cyclins in regulating cell growth and progression through the cell cycle.
  • Cyclins are essential proteins that control the progression of cells through the different stages of the cell cycle by activating cyclin-dependent kinases (CDKs). As cells grow and prepare to divide, specific cyclins accumulate and bind to their corresponding CDKs, leading to phosphorylation events that drive key transitions in the cycle. This regulation is vital because it ensures that cells do not progress to mitosis until they are adequately prepared, preventing errors that could lead to uncontrolled growth or cancer.
• Evaluate how external factors influence cell growth and what implications this has for understanding diseases like cancer.
  • External factors such as nutrient availability, growth signals from other cells, and environmental conditions play a significant role in regulating cell growth. For instance, inadequate nutrients can halt growth, while excess growth factors can lead to uncontrolled proliferation. Understanding how these external influences affect cell growth is crucial in cancer research, as many cancers arise from mutations that disrupt normal growth regulation pathways. By targeting these pathways or restoring proper regulatory mechanisms, new treatments can be developed to control abnormal cell growth associated with cancer.

Related terms

interphase: The phase of the cell cycle where the cell grows, duplicates its DNA, and prepares for mitosis.

mitosis: The process of cell division where a single cell divides into two identical daughter cells.

cyclins: Proteins that regulate the cell cycle by activating cyclin-dependent kinases (CDKs), crucial for controlling the progression through different stages of the cycle.