<span>Proliferation of lymphocytes occurs immediately after activation, as well as the encounter of antigen. First, these antigen are bound, after which activation begins. Activation immediately leads to proliferation, as well as differentiation. Proliferation is an increase in the number of something, in this case, in the number of lymphocytes, or white blood cells. </span>
Answer:
B. decreases salivation and increases blood pressure
Explanation:
The sympathetic nervous system is part of the autonomous nervous system which controls involuntary responses of the body such as salivation and blood pressure.
The sympathetic nervous system is majorly responsible for body actions that are produced when threat is perceived. It generates responses referred to as the “fight or flight” response. Examples of such responses include, increased breathing, increased high blood pressure, dilation, decreased salivation, etc.
Activation of the sympathetic nervous system would result in rise in the blood pressure as can be witnessed by someone whose body has perceived a threat or reacting to a stressful situation.
The control of salivary production by the sympathetic nervous system leads to the release of noradrenaline which acts on certain receptors that results in decrease in the production of saliva. This is evident in a person that is facing a threat also.
A. 12.5 m/s.
The average speed is defined as the relationship between the displacement made by a body and the total time it took to perform it.
The formula that will allow you to calculate the average speed is:
v = d/t, where d is the traveled distance and t the time it took to travel the distance.
We hace to convert 4 minutes to second:
(60 s/1 min)*(4 min) = 240 s
So, the average speed is:
v = 3000 m/240 s
v = 12.5 m/s
