Answer:
C. Platelet adhesion
Explanation:
Platelet adhesion comes first in the process of hemostasis.
The process of hemostasis has got three phases:
- Vascular spasm
- Platelet plug formation
- Blood coagulation
The process occurs in the body in the event of a bleeding injury.
In the first phase, damaged blood vessels constrict to prevent more bleeding.
In the second phase, platelets adhere to damaged endothelium to form platelet plug.
In the third phase, fibrinogen is converted to fibrin to form a clot.
Antigens are found on the surface of viruses
Answer:
This hormonal control of blood glucose levels is an examples of negative feedback response.
Explanation:
The blood glucose concentration maintain their concentration through negative feedback mechanisms.Alpha and beta cell present in pancreas. Alpha and beta cell produced insulin and glucagon which act as a antagonistic hormones and control blood glucose level.
Insulin is secreted by beta cell.Beta cell secreted insulin when glucose level increased in the blood.Insulin helps to stimulate liver to absorb glucose.Liver convert glucose to glycogen and adipose cells convert the glucose to the fat.In response, glucose concentration decreases in the blood, and insulin secretion discontinues (through negative feedback from declining levels of glucose)
Glucagon is secreted by alpha cells. when the concentration of blood glucose level drops then alpha cells secrete glucagon into the blood.Glucagon stimulates the liver for release of glucose. When blood glucose levels return to normal then glucagon secretion stopped.Its a negative feedback response.