"If blood temperature rises too high<span>, this is sensed by specialized neurons in the hypothalamus of the brain. ... As these blood vessels dilate, more blood flows close to the </span>body<span> surface and excess heat radiates from the </span>body<span>."</span>
A semipermeable membrane is a membrane that allows certain substances to pass through it. The most accurate definition is the third choice, "It is a barrier with tiny openings that let some, but not all, materials pass through." hope this helps:)
This is called passive immunity. Passive in such a way that the vaccine came from another human blood plasma which contains antibodies that temporarily combats disease-causing virus/bacteria. Vaccination with gamma globulin transiently boosts patient's immunity against illnesses or diseases.