According to Annenberg Learner, when the synthesis of certain growth factors is inhibited, cells stop dividing. Normal cells display contact inhibition as they respond to forms of contact from other cells by causing cell division to end.
Cells age, die and are then replaced by newer cells. Apoptosis is the programmed and normal death of a cell. Normal cells are able to divide approximately 50 times before they are replaced. This process is related to the replication of DNA, which is limited. Every time the chromosomes in the cell replicate, the telomeres shorten. In the growing of new cells, telomerase replaces the lost telomeres.Learn More
Animal cells are eukaryotic cells, or cells that contain a membrane-bound nucleus. The nucleus holds the DNA of the cell that provides the cell with instructions for life.Full Answer >
Clara cells are dome-shaped cells found in the bronchioles of the lungs that have short microvilli. Clara cells are also known as bronchiolar exocrine cells.Full Answer >
Stem cells are important to medicine for their potential as all-purpose tools for restoring health in patients who need organ or tissue repair. Stem cells are naturally used by adult bodies to grow fresh tissue at sites of infection or damage.Full Answer >
Cells were discovered in 1665 by Robert Hooke, whose findings were published in the book "Micrographia." The second scientist to observe cells was Anton van Leeuwenhoek. In his work, he discovered bacteria, as well as sperm and egg cells, which disproved the theory of spontaneous generation. Hooke later confirmed van Leeuwenhoek`s findings.Full Answer >