Which of the following best describes a symbiotic relationship? responses striped bass and bluefish eat the same variety of mackerel. striped bass and bluefish eat the same variety of mackerel. intestinal bacteria inhabit the gut of humans. intestinal bacteria inhabit the gut of humans. mountain lions feed on white-tailed deer. mountain lions feed on white-tailed deer. marsupial animals carry their young in a pouch.
The Correct Answer and Explanation is :
The correct answer is: intestinal bacteria inhabit the gut of humans.
Explanation:
A symbiotic relationship refers to a close, long-term interaction between two different species that can be beneficial, neutral, or harmful to one or both species involved. There are three primary types of symbiosis: mutualism, commensalism, and parasitism.
- Mutualism is a type of symbiosis where both species benefit from the relationship.
- Commensalism is when one species benefits and the other is neither helped nor harmed.
- Parasitism occurs when one species benefits at the expense of the other, causing harm.
In the case of intestinal bacteria inhabiting the gut of humans, this is a mutualistic relationship. The bacteria in the human digestive system help break down food and synthesize certain vitamins (like vitamin K and some B vitamins), which are beneficial to the human host. In return, the bacteria receive a stable environment and nutrients from the human body. This relationship benefits both species: humans gain nutritional benefits, and the bacteria obtain a habitat and food source.
Now let’s look at the other examples:
- Striped bass and bluefish eating the same variety of mackerel is an example of competition, not symbiosis. Both species are vying for the same food source, which could harm one or both if resources are scarce.
- Mountain lions feeding on white-tailed deer is an example of predation, not symbiosis. The mountain lion benefits by eating the deer, while the deer are harmed by being killed for food.
- Marsupial animals carrying their young in a pouch is a biological feature, not a form of symbiosis. This is related to reproduction and does not describe an interaction between two different species.
Thus, the relationship between intestinal bacteria and humans is the only one that fits the definition of symbiosis, specifically mutualism.