Answer:
Sympathetic nervous system
Explanation:
The sympathetic nervous system of the autonomic division prepares the body for stress or emergency conditions by generating the “fight-or-flight” responses. The sympathetic nervous system triggers the release of stress hormones from the adrenal medulla to generate the set of physiological responses.
There is dilation of the pupil, and an increased rate of heartbeat and increased blood pressure. Other responses include dilation of airways and dilation of blood vessels that supply blood to skeletal muscles, heart muscles, liver, etc. Under the given emergency condition, the sympathetic nervous system of Meghan was activated to generate the fight or flight response.
Think it’s answer D but it maybe B
hope this helps!!
sorry if it’s wrong
<span>The answer is A.
Invasive species are species that thrive unregulated
in an introduced environment/ habitat and
affect the biodiversity of the environment.
They boom unchecked mostly due to lack of a natural predator. Therefore, introducing
a predator will limit their growth. </span>
DDT stands for dichloro-diphenyl-trichloroethane. The first kind of synthetic/artificial insecticides came into use in the 1940s. The earlier usage of DDT include: a) Killing of malarial vectors, b) Combatting Typhus and other insect borne human diseases, c) As a pest control in crops d) as a pest control in garden, live stock production and even at homes.
The negative impact of DDT could be felt for the first time when the pests that were earlier killed by use of DDT have now become pesticides resistant. In the 1950s in USA, the regulatory measures were adopted to reduce the usage of DDTs as its effects as a pesticides were no more long significant and also it was creating detrimental physical and psychological impacts on the human and environment.
It was in 1972 that the U.S. Environmental Protection Agency cancelled the order for banning the usage of DDT based on the adverse impact it produced on the environment, human and other life forms. Since then continuous studies are being conducted to analyse the impact of DDTs. In some later years it was established that DDT is the cause of producing tumors in liver.
Some of the common negative impacts produced by DDT as per the U.S. Department of Agriculture :
a) The non destructive nature – DDT can not be destroyed and thus it remains persistent in the atmosphere
b) It attacks the tissues of living organisms especially the animals and humans ( fatty tissue)
c) It can penetrate the atmosphere to deeper extent.
Now as per the current stuation, The use of DDT is controlled and other alternatives of pest control organisms is being deduced. As per the treaty of Stockholm Convention on POPs (Persistent organic pollutants) , usage of DDT for malarial control is justified but it puts a restrictive use of DDT as pesticides in other areas.
