**multiple answers**
the body has many responses to injuries, diseases and other conditions that alter its normal function. select the statements that indicate the body's responses to an injury, such as a cut.
a) platelets join together to form a clot.
b) macrophages collect damaged cells and other foreign substances.
c) red blood cells transport pathogens to the injury site.
d) if the wound is infected, fever may occur to heighten the immune response.
e) cytokines alert the immune system to possible infection.
f) the central nervous system reduces signals from the area to decrease pain.

Juan and carol were studying invertebrates in biology. they knew that segmented or earth worms preferred a dark, moist habitat. during this lab, they would be investigating the responses of organisms called planaria or dugesia tigrina. these were simple flatworms that still had a one-way digestive system and a very simple nervous system. juan and carol placed the planaria in a petri dish containing cool, distilled water that was partially covered with black paper. they shined a light on the dish. next, they removed the paper and placed a small amount of chicken liver at one end of the dish. they added a few large salt crystals to the water. finally, they added drops of hot water to the cool water in the petri dish. their results can be seen in the data table. according to their experiment, all but one conclusion is valid.

What are antigens and antibodies? how are they involved in the body’s response to incompatible blood?

If the dimensions of a cube-shaped cell with a length, height, and width of 1 micrometer were to double, what would be the cell's new ratio of surface area to volume? a.3 to 1 b.4 to 3 c.1 to 2 d1 to 6