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Parthenogenesis

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Parthenogenesis

  1. 1. Honeybees have haplodiploid sex determination. In humans, an X chromosome and a Y chromosome means that you’ll be a male (typically). Two X chromosomes will be a female. But bees do things differently; the queen bee will lay a ton of eggs, and these unfertilized eggs will each have one sex chromosome. If a male worker bee fertilizes an egg, it will develop into a female bee. Otherwise, the unfertilized eggs develop into males. Thus female bees have two sets of sex chromosomes (we term them ‘diploids’) and male bees only have one set of sex chromosomes (haploids). What is Parthenogenesis? The word parthenogenesis originates from the Greek language meaning virgin birth. Parthenogenesis is a form of reproduction where the unfertilized egg will develop into a DRONE BEE. This asexual reproduction occurs in various species in nature. How Parthenogenesis was discovered? J. A. Janis wrote that a new QUEEN BEE will hatch from an ordinary fertilized egg. He also claimed that an unmated QUEEN BEE will lay eggs from which will only be born DRONE BEES. Important Research Task and Experiment J. A. Janis performed an experiment and discovered that in late beekeeping season a selected hive with the young BEE LARVAE and WORKER BEES and without the QUEEN BEE produced a new QUEEN BEE that could not mate at all. Janis wrote about this with excitement particularly when this QUEEN BEE laid eggs into the WORKER BEE cells from which hatched only small DRONE BEES. Also J. A. Janis denounced A. G. Schirach's thought that from any egg will be born a WORKER BEE. Fertilized or Unfertilized Eggs of Bees Fertilized eggs will develop into a QUEEN BEE or WORKER BEE but this depends on the size and type of the cells and on the composition of food fed to the BEE LARVAE by the WORKER BEES. The QUEEN BEE cells are the largest built by WORKER BEES on the honeycombs. The DRONE BEES are always born from unfertilized eggs. The drone bee cells are 15 percent larger than the worker bee cells. Kinship and Bees The QUEEN BEE mates with numerous DRONE BEES high in the air. The polyandry in honey bees and the phenomenon of parthenogenesis creates a superorganism in a beehive colony. The WORKER BEES who share the same father (DRONE BEE) are called SUPER SISTERS because they are more closely related to each other than their SISTERS who have different fathers (DRONE BEES). Types of Honey Bees (Apis mellifera) in a Hive 1. The QUEEN BEE is the only mated female in a hive. 2. The WORKER BEES cannot mate with the DRONE BEES.
  2. 2. 3. The DRONE BEES are male bees and mate with a virgin QUEEN BEE high in the air outside her hive. Age of Worker Bee is Important Newborn WORKER BEES clean out the honeycombs two days after their birth. During the next three weeks these bees perform various duties that run to a precise timetable. Afterwards they fly out to collect pollen or nectar or water and propolis which they will eat or use or store in their hive. Complicated Flowers and Bees What came first on Earth? Was it a bee or a flower? Complicated flower structures require bees with the exact body sizes and tongue lengths to pollinate them. The Echium vulgare is an example: it bears purple tubular flowers which allow only the bee (Apis mellifera) to reach their nectaries. This is an example of an excellent interaction between honey bees and flowers. Without honey bees there would be no flowers and without flowers there would be no honey bees. Pollination and Honey Bees Any beekeeper is very valuable for keeping honey bees by his or her contribution to pollination. It is not easy to place a money value on it. This pollination is very important that even farms that raise cows depend on honey bees to help grow quality Alfalfa for them. Alfalfa plants pollinated by insects other than honey bees will produce a yield of 125 lbs. (57.7 kg) of seeds from the 2.5 acres (1.11 hectare) compared with a yield of 441 lbs. (200 kg) when alfalfa plants will be pollinated by the honey bees.

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