During which era did plants first appear on land?

cenozoic

mesozoic

paleozoic

precambrian

Listed in the item bank are some key terms and expressions associated with the categories seen in the venn diagram. to find out more information about items, some have more details available when you click on them. drag and drop each item onto the proper area of the diagram. if an item describes more than one category, be sure to place it in the overlapping space. viruses are tiny infectious pathogens that cause many different diseases, such as polio, and the flu. though they are similar to one celled organisms in some ways, in many ways they are very different. use the venn diagram below to show the similarities and differences between viruses and living organisms.

The human genome project is devoted to mapping the general dna sequence of our species. this could lead to the development of new medicines, as well as the possibility of using gene therapy to treat certain diseases. however, there are some ethical issues surrounding the mapping of individual genomes. one concern is a) that your genes may change over time, making the project useless. b) that insurance companies could discriminate based on genetic make-up. c) that since this has never been done before, we should probably not do it now. d) that sequencing our individual genomes is so expensive, it is a counter-productive strategy.

Most animal cells membranes have proteins that pump ions out of the cell and potassium ions into the cell