You are here: Urology Textbook > Index > Apoptosis
Apoptosis: Programmed Cell Death
Definition of Apoptosis
Apoptosis is cell death, controlled by gene expression, which includes, in contrast to necrosis, the avoidance of cytokine release or inflammation triggering.
Mechanisms of Apoptosis
- signal transduction (external or internal stimuli)
- Shrinkage of the cell
- Bubble-like protrusions at the cell surface
- Condensation and degradation of DNA
- Degradation of mitochondria
- Fragmentation of the cell into small membrane-bound fragments (apoptotic bodies)
- Exposure of the phospholipid phosphatidylserine on the surface of apoptotic bodies
- Phagocytosis of apoptotic bodies by macrophages
Significance of Apoptosis
Apoptosis (controlled cell death) is essential for normal development and body functions:
- Control of growth and size of tissues
- Control of embryogenesis
- Elimination of potentially harmful cells
- Selection of genetically intact germ cells
- Selection and reduction of unnecessary or potentially harmful cells of the immune system
- Disorders of apoptosis can lead to cancer or autoimmune diseases
Go Back |
If you have deactivated JavaScript, please use the Back button of your browser.
Index: 1–9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
References
Deutsche Version: Apoptose
Urology-Textbook.com – Choose the Ad-Free, Professional Resource
This website is designed for physicians and medical professionals. It presents diseases of the genital organs through detailed text and images. Some content may not be suitable for children or sensitive readers. Many illustrations are available exclusively to Steady members. Are you a physician and interested in supporting this project? Join Steady to unlock full access to all images and enjoy an ad-free experience. Try it free for 7 days—no obligation.