<span>C. Gametes are the sex cells, and each (sperm and ovum) contain half of the parent's genetic material. These cells will fuse to produce a zygote, which will usually contain the full number of genes required by an organism to live. If there is a chromosomal abnormality, such as a gamete with an extra chromosome, the offspring can either die in development or sometimes be born with physiological and/or developmental difficulties. An example of this phenomenon is trisomy 21, also known as Down Syndrome, in which the 21st chromosome bears 3 copies instead of the regular 2.</span>
<span>Chromated copper arsenate, or CCA, is a pesticide that has been used for years in
pressure-treating lumber to prevent destruction from rot and insects. Arsenic, a toxic
chemical, can leach from this treated wood, leaving residues on the wood’s surface and in
nearby soil. Young children who play on or near decks or playscapes made from CCA-
treated wood can get arsenic on their skin and into their bodies, especially if they eat or
drink without washing their hands.
Because of the health risks of long-term exposure to arsenic, the Environmental
Protection Agency (EPA) has announced that as of December 31, 2003, arsenic Currently the EPA does not recommend that people remove existing structures made with CCA-treated wood or the soil surrounding those structures. However, they do recommend that people reduce their potential exposure to arsenic.</span>
Virus: an infective agent that typically consists of a nucleic acid molecule in a protein coat, is too small to be seen by light microscopy, and is able to multiply only within the living cells of a host.
Bacteria: a member of a large group of unicellular microorganisms which have cell walls but lack organelles and an organized nucleus, including some which can cause disease.
Fungi/fungus: any of a group of spore-producing organisms feeding on organic matter, including molds, yeast, mushrooms, and toadstools.
Protozoa: a phylum or group of phyla that comprises the single-celled microscopic animals, which include amoebas, flagellates, ciliates, sporozoans, and many other forms. They are now usually treated as a number of phyla belonging to the kingdom Protista.
DNA needs to replicate before cells divide to give the complete set of genetic instructions to its daughter cells, (or ensures that each new cell inherits all of the genetic traits of the parent cell).
Hope this helps! :D
~PutarPotato
