Question

Which interaction BEST illustrates the concept of mutualism?

A) Jaguars feeding on wild pigs.
B) Squirrels playing with other squirrels.
C) Malaria protozoans living on the blood of a host.
D) Nitrogen-fixing bacteria in root nodules of legumes.

Answer 1

Nitrogen-fixing bacteria in root nodules of legumes. This is an illustration of a relationship that both organisms need

Answer 2

D) Nitrogen-fixing bacteria in root nodules of legumes.

Step-by-step explanation:

Mutualism is when organisms of two different species interact benefiting both in some way. This can involve the exchange of resources, such as shelter, food or nutrients, or the exchange of services, such as protection, transportations, and healthcare. Mutualism is very important in ecology.

In this case, the nitrogen-fixing bacteria invade the root hairs of host plants, multiplying and stimulating the formation of root nodules, enlargements of plant cells and bacteria in intimate association. In the nodules, the bacteria transform free nitrogen to ammonia, wich the host plant uses for developing.