Which is an external stimulus?

A. Thirst

B. Hunger

C. Pain

D. Heat

The walls of the alimentary canal share a common pattern from esophagus to anus. how many layers make up the wall?

Why can't a virus reproduce on its own? will give Brainliest

What are some things we can do to reduce the negative impact humans are causing?

Unlike incomplete metamorphosis, complete metamorphosis

A group of scientists wants to test the effects of increased salinity on a population of catfish in a river. what result from this experiment would confirm that natural selection is a process that can drive evolution?

Does one molecule of atp contain more energy than one molecule of glucose

Which types of organisms are most vulnerable to overfishing, and why? A. Small fish that live a short time and reproduce quickly, since their population numbers are always highest. B.

Which comes first: embryonic development or fetal development?

True or false: During meiosis, two rounds of DNA synthesis are required to form four gametes from one parent cell.

In 1665, Robert Hooke, an English scientist, published his book Micrographia, in which he described that pieces of cork viewed under a microscope presented small cavities, similar to pores and filled with air.