The walls of the small intestine are folded by what?

The small intestine is the part of the gastrointestinal tract where the absorption of nutrients and minerals occurs. Because of that, surface of the small intestine needs to be increased. The inner wall (mucosa) is lined with epithelial tissue and covered with folds called plicae circulares. From the plicae circulares extend finger-like pieces of tissue called villi. The individual epithelial cells of mucosa also contain finger-like extensions-microvilli. Thus, plicae circulares, villi and microvilli are structures that improve absorption by increasing the surface of small intestine.

false because ozone (o3) depletion does not cause global warming, but both of these environmental problems have a common cause: human activities that release pollutants into the atmosphere altering it.

global warming is caused primarily by putting too much carbon dioxide into the atmosphere when coal, oil, and natural gas are burned to generate electricity or to run our cars.

explanation:

answer: a) a compound microscope has a greater magnification ability than a simple microscope.

explanation: