Growth factors are local regulators that
a. Are produced by the anterior pituitary.
b. Are modified fatty acids that stimulate bone and cartilage growth.
c. Are found on the surface of cancer cells and stimulate abnormal cell division.
d. Bind to cell-surface receptors and stimulate growth and development of target cells.

Verified step by step guidance

1. Understand the role of growth factors: Growth factors are proteins that play a crucial role in regulating cellular processes such as growth, proliferation, and differentiation.
2. Analyze option a: Consider whether growth factors are produced by the anterior pituitary. The anterior pituitary produces hormones like growth hormone, but growth factors are typically produced by various cells throughout the body.
3. Analyze option b: Determine if growth factors are modified fatty acids. Growth factors are proteins, not fatty acids, so this option is incorrect.
4. Analyze option c: Evaluate if growth factors are found on the surface of cancer cells. While growth factors can influence cancer cell behavior, they are not located on the cell surface; rather, they bind to receptors on the cell surface.
5. Analyze option d: Consider if growth factors bind to cell-surface receptors. Growth factors typically bind to specific receptors on the surface of target cells, triggering signaling pathways that lead to growth and development, making this option the most accurate.

Key Concepts

Growth Factors

Growth factors are proteins or hormones that play a crucial role in regulating cellular processes such as growth, proliferation, and differentiation. They bind to specific receptors on the surface of target cells, triggering a cascade of intracellular signals that promote cell division and development. Understanding their function is essential for comprehending how cells communicate and respond to external stimuli.

Cell-Surface Receptors

Cell-surface receptors are specialized proteins located on the cell membrane that bind to external molecules like growth factors. This binding initiates signal transduction pathways, leading to various cellular responses. These receptors are vital for cells to perceive and react to their environment, influencing processes like growth, immune responses, and cellular communication.

Signal Transduction

Signal transduction is the process by which a cell converts an external signal into a functional response. It involves a series of molecular events, including receptor activation, secondary messenger release, and activation of specific genes. This mechanism is fundamental for understanding how growth factors influence cellular activities, ensuring proper growth and development.