What is the main difference between primary and secondary succession? A. Primary succession involves plant populations, and secondary succession involves animal populations. B. Primary succession occurs on land, and secondary succession occurs in aquatic environments. C. Primary succession occurs on barren land, and secondary succession occurs where soil is present. D. Primary succession occurs overnight, and secondary succession occurs over hundreds of years.

What is an endocrine function? (apex) a.esophageal glands release mucus into the esophagus b.salivary glands release saliva into mouth c.swear glands release sweat to the skin d.the pineal gland releases melatonin into the bloodstream

Ineed to get this test done which of the following statements is correct in hour our immune system responds to a potential pathogen? a.) the skin will be the first line of defense, and then the many phagocytes in the bloodstream will attempt to consume the possible pathogen. b.) b cells will start reading the antigen code immediately and call t cells to assist in destroying the pathogen. c.) the adapted immune system will call on the innate immune system to destroy the pathogen. d.) the t-cells in the adapted immune systems are the first to recognize the pathogen

Natural resources are any materials that humans obtain from the earth to meet our wants and needs.