The invasion of unwelcome species can be stopped at all of the following points except

(a.) before reproduction

(b.) after they are found

(c) before the introduction

(d) after they are established

Select all the correct answers. lactobacillus is a bacteria that live inside humans. these bacteria live on the nutrients from our bodies. they to keep our gut clean and healthy. s. typhi is a bacteria that enter our bodies through contaminated food. this bacteria causes infections in the body. based on this information, which two statements about the association between these bacteria and humans are true? a. lactobacillus shares a parasitic relationship with humans. b. s .typhi shares a parasitic relationship with humans. c. both lactobacillus and s. typhi share a parasitic relationship with humans. d. both lactobacillus and s. typhi share a mutualistic relationship with humans. e. lactobacillus shares a mutualistic relationship with humans, and s. typhi shares a parasitic relationship multiply chrse

On a recent expedition to a remote region of northern canada, scientists uncovered skeletal remains from about 100,000 years ago. surprisingly, all the skeletal remains, which included many species from differing biological families and spanned about two thousand years, showed evidence of experiencing temperatures in excess of 1000 degrees fahrenheit (or 538 degrees celsius). which of the following, if true, best explains the apparent paradox between the cold environment and the evidence of the bones experiencing hot temperatures? (a) chemical changes that naturally occur during the process of decay in only one north canadian species produce the same evidence of the species' skeletons being exposed to hot temperatures as the expedition scientists found. (b) a little over 103,000 years ago, a large fire is known to have occurred in northern canada. (c) strong evidence exists that as early as 70,000 years ago, homo sapiens around the world relied heavily on fire to cook animals. (d) in the same expedition and in roughly the same layer of excavation, scientists found rudimentary wood cutting and hunting tools used by early humans.

Ascientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas which group of statements best describes all of the materials he is using in the investigation?