PSYC 2000 Lecture Notes - Lecture 15: Ploidy, Nuclear Membrane, Mitosis
Document Summary
In mitosis, we do not divide haploid cells to create new haploid cells, however, this does happen in some living organisms. Can work due to the chromosomes lining up in the middle so that each new cell gets same amount of chromosomes. Triploid = 3n - 3 chromosomes ones. Longest chromosome = longest, chromosomes get shorter as they go up the number scale. Haploid = egg and sperm or gametes (sex cells) Mitosis - make new cells from preexisting cells. Starts with a diploid cell found in sex cells or testes and ovaries (sex organs) Receive signals from surrounding cells that tell them to divide twice. Diploid cells divide into two, those two diploid divide again to produce four haploid. Cells go through s phase in cell cycle to replicate dna. Both meiosis and mitosis require chromosomes to be duplicated for it to take place - doubling of genetic material.
