Which of the following scenarios can be classified as a positive feedback loop? 1.increase in blood pressure to reduce the heart rate
2.increase in red blood cell production due to low oxygen levels
3.sweating to cool down skin cells
4.increased platelet production to help blood clotting

D

Explanation:

In order to prevent blood loss, the body needs a mechanism that amplifies the action that leads to clotting in a short period of time. This cascade or enhancement of a process is a positive feedback mechanism.

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation:

this protocol provides a detailed procedure for co-immunoprecipitation (co-ip) to identify protein–protein interactions.