Answer:
b.the influence of humans on a natural system can have unpredictable negative impacts
Explanation:
The situation described best illustrated the fact that the disturbance of natural ecosystem by humans can have unpredictable negative impacts.
<em>Option c is incorrect because human alteration of the ecosystem needs to be continuously studied to avoid ecological disasters.</em>
<em>Option d is incorrect because alteration of the ecosystem does not always end up in the pollution of the ecosystem and loss of finite resources.</em>
<u>While human alteration of the natural ecosystem often have long term negative impacts, many of these impacts can not be predicted until they happen. This makes option b to be more complete than option a.</u>
The correct option is b.
According to the history and physical examination of the patient, the patient may have a upper gastrointestinal bleed most probably from a bleeding peptic ulcer. A bleeding peptic ulcer can cause abdominal pain and vomiting described as coffee ground vomit because of the reaction of the blood with the stomach acids. The patient's vital signs signify that the patient is in the state of hypovolemic shock. The emergency medicine consultant should use an oxygen mask with caution because additional vomiting episodes may recur and if the patient is wearing an oxygen mask, the vomit cannot be cleared thoroughly and may even cause aspiration.
Invasive exotic species are species that interfiere with the natural food chain and are usually foreign
Role of decomposer in fooe chain/food web
Decomposers are organisms which convert complex organic molecules into their simple forms.
Example
bacteria, fungi etc.
Explanation
food chain stary from autotrophs and end at decomposers. these organisms are present in soil, rely on dead bodies of plants and animals for their nutrient requirements. These organisms possess strong enzymatic system, which scavenge comples molecules from dead bodies during respiration and convert them into simple nutrients which return back to atmosphere.