What is the function of thrombocytes?
A.
Defined against infection.
B.
Play a role blood clotting.
C.
Transport respiratory gases.
D.
Form connective tissue.
The Correct answer and Explanation is:
The correct answer is B. Play a role in blood clotting.
Thrombocytes, commonly known as platelets, are crucial components of the blood that play a vital role in the clotting process, which is essential for stopping bleeding and maintaining vascular integrity.
Function of Thrombocytes
- Platelet Formation and Structure:
- Thrombocytes are small, disc-shaped cell fragments derived from larger cells called megakaryocytes in the bone marrow. They lack a nucleus but contain various granules and organelles necessary for their function.
- Role in Hemostasis:
- Primary Hemostasis: When a blood vessel is injured, platelets are the first responders. They adhere to the exposed collagen and other components of the damaged vessel wall. This adherence is mediated by specific surface receptors and is crucial for the initial platelet plug formation.
- Platelet Activation: Once adhered, platelets become activated and release various chemical signals, such as adenosine diphosphate (ADP), thromboxane A2, and serotonin, which further recruit and activate additional platelets to the site of injury.
- Platelet Aggregation: Activated platelets stick to each other, forming a temporary plug that covers the breach in the vessel wall. This process is facilitated by fibrinogen, which binds platelets together through specific receptors on their surface.
- Secondary Hemostasis:
- In addition to forming a plug, platelets also play a role in stabilizing the clot. They provide a surface for the activation of clotting factors, which are proteins in the blood that work together to form a more stable and durable fibrin clot. This clot prevents further bleeding and allows time for tissue repair.
- Clot Retraction and Healing:
- Once the clot is formed, platelets help in clot retraction, a process that tightens and compresses the clot, facilitating the healing of the vessel. This retraction also helps to approximate the edges of the wound, aiding in tissue repair.
In summary, thrombocytes are integral to hemostasis, ensuring that blood loss is minimized after vascular injury and supporting the repair process of damaged tissues. Without proper platelet function, individuals would be at risk of excessive bleeding and difficulty in wound healing.