How do endocrine glands differ from other body glands, such as sweat glands?

The energy needs of a human population are not affected by

Some birds look for food near cattle and other livestock. the movement of the cattle churns up the ground, making insects available to the birds. the cattle appear to be unaffected by the presence of the birds. what kind of relationship exists between the birds and the cattle? o a. parasitism o b. commensalism o c. predation o d. mutualism

What type of plant is good for a bioassay and where can i buy it? i only have a month.