What is the difference between xylem and phloem?

What has happened to the endosperm that formed in the embryo sac?

An example of a multicellular green alga is a. Ulva. c. Volvox. b. Chlamydomonas. d. Fucus.

A scientist started with a culture of 20 bacteria in a dish. the number of bacteria at the end of each successive hour increased exponentially, so that the number at the end of one day was 220.

The pH of water is because it contains an equal amount of H * and OH ions.

Which of the following is a main difference in cell structure between an onion cell and a human cheek cell?

Which of the following is a constructive process? deposition detachment transport plucking

Coal deposits were formed from? A. Plant life in ancient B. Ancient plankton and marine life C. Freshwater organisms from the last 100,000 years D. Modern plants and animals

According to the Hardy-Weinberg principals, which of the following can prohibit genetic equilibrium?

Rickettsia are obligate intracellular parasites that are transmitted by arthropods. In which of the following places would you most likely find the parasites living in the host organism during the course of infection? A.

How are viruses able to move between species?