Apoptosis: Programmed Cell Death Overview

Visible signs include shriveling of the nucleus, broken bits of the membrane, and the formation of apoptotic bodies.

Caspases are a family of cysteine proteases that play crucial roles in the process of programmed cell death, or apoptosis.

Killer lymphocytes bind to death receptors on target cells, activating procaspase molecules and initiating a caspase cascade.

<p>The release of cytochrome c from mitochondria triggers the intrinsic pathway.</p> Signup and view all the answers

<p>Macrophages are signaled to engulf apoptotic cells, ensuring their clean removal.</p> Signup and view all the answers

<p>Apaf-1 binds to cytochrome c and aggregates procaspase-9 molecules, facilitating the caspase cascade.</p> Signup and view all the answers

<p>Apoptotic bodies are small vesicles formed as a result of cell membrane fragmentation during apoptosis.</p> Signup and view all the answers

<p>The extrinsic pathway is triggered by death ligands activating receptors, while the intrinsic pathway is initiated by signals from within the cell, involving mitochondria.</p> Signup and view all the answers

<p>Apoptosis is programmed cell death that involves a coordinated collapse of cells. It is essential for proper development, maintaining tissue homeostasis, and eliminating damaged or unnecessary cells.</p> Signup and view all the answers

<p>The resorption of the tadpole tail and the formation of fingers and toes in a developing fetus.</p> Signup and view all the answers

<p>Cells may undergo apoptosis due to DNA damage or viral infection.</p> Signup and view all the answers

<p>Caspases are enzymes that initiate the apoptotic process by breaking apart the cell's internal structure and activating other enzymes that dismantle DNA.</p> Signup and view all the answers

<p>In apoptosis, cells condense and remain intact before phagocytosis, while necrotic cells swell, lyse, and trigger an inflammatory response.</p> Signup and view all the answers

<p>Apoptosis can be induced by the withdrawal of positive signals, such as growth factors, or by receiving negative signals like DNA damage or oxidative stress.</p> Signup and view all the answers

<p>ATP is required for the execution of apoptosis, whereas its depletion is characteristic of necrosis.</p> Signup and view all the answers

<p>In apoptosis, DNA fragmentation occurs in a ladder-like pattern, which is distinctive from the random fragmentation seen in necrosis.</p> Signup and view all the answers

A tightly controlled process of cell death involving a series of biochemical events that lead to the dismantling of the cell.

A cell's internal process, triggered by specific signals, that leads to its own dismantling.

Apoptosis's key role in shaping developing organisms by eliminating unnecessary or faulty cells. It ensures properly formed structures.

Apoptosis's role in maintaining a healthy immune system by getting rid of harmful cells like those infected with viruses.

Factors like growth factors and cytokines that signal a cell to survive and grow.

Factors like DNA damage, oxidants, and death activators that trigger a cell's apoptosis pathway.

Uncontrolled cell death often caused by external factors like injury or toxins, characterized by swelling and bursting.

Apoptosis differs from necrosis in that it's controlled, doesn't cause inflammation, and involves DNA fragmentation.

A family of cysteine proteases that play a crucial role in programmed cell death (apoptosis).

Enzymes that break down proteins by cleaving peptide bonds.

A pathway of apoptosis triggered by external signals. Death ligands (like Fas ligand) bind to death receptors on the target cell's surface, activating a cascade of caspase activation. This ultimately leads to cell death.

A pathway of apoptosis initiated internally by signals within the cell. Release of cytochrome c from mitochondria triggers the formation of the apoptosome complex, which then activates caspases, resulting in cell death.

A protein that facilitates the release of cytochrome c from mitochondria, leading to caspase activation and apoptosis.

A multi-protein complex formed during the intrinsic apoptotic pathway. It is composed of cytochrome c, Apaf-1, and procaspase-9. The apoptosome complex activates caspase-9, initiating the caspase cascade.

Apoptosis is a controlled process of cell death that doesn't trigger inflammation. It involves a cascade of enzymatic reactions, primarily mediated by caspases, leading to the dismantling of the cell. This process is crucial for normal development and eliminating damaged cells.

Apoptosis is a natural process of cell death that is crucial for normal development and removing damaged or unwanted cells. Unlike necrosis, apoptosis doesn't trigger an inflammatory response. This regulated process involves the activation of caspase enzymes which dismantle the cell's internal machinery.