Gen bio 2

• Binary Fission


  The separation of a parent into two or more individuals of approximately equal size
• Budding


  New individuals arise from outgrowths of existing ones; the offspring may either
• Fragmentation


  The breaking of the body into several pieces, some or all of which develop into complete adults
• Regeneration


  The regrowth of lost body parts; usually accompanied with fragmentation
• Internal Reproduction


  The male generally delivers sperm cells directly into the body of the female. Her moist tissues provide the watery medium required for movement of sperm
• External Reproduction


  Mating partners usually release eggs and sperms into the water simultaneously
• Metagenesis


  Also known as 'transformation development', refers to an alternation of asexual and sexual generations
• Parthenogenesis


  Also known as 'virgin development', an unfertilized egg develops into an adult animal. This occurs for several generations, after which males develop, produce sperm, and mate with females to fertilize their eggs
• Hermaphroditism


  Means that a single organism produces both eggs and sperm. Although this form of reproduction is still classified as sexual, it is an exception to the important generalization that sexual reproduction involves two different individuals
• Vasocongestion


  The filling of a tissue with blood caused by increased blood flow through the arteries of that tissue
• Myotonia


  Increased muscle tension of both skeletal and smooth muscles
• Excitement Phase


  1. Preparation of penis and vagina for coitus (sexual intercourse)

  2. Vasocongestion is particularly evident in erection of the penis and clitoris; enlargement of the testes, labia, and breasts; and vaginal lubrication

  3. Myotonia may occur, resulting in nipple erection or tension of the arms and legs
• Plateau Phase


  1. Responses in excitement phase continue

  2. In females, the outer third of the vagina becomes vasocongested, while the inner two-thirds slightly expands

  3. This change, coupled with the elevation of the uterus, forms a depression that receives sperm at the back of the vagina
• Orgasm Phase


  1. Characterized by rhythmic, involuntary contractions of the reproductive structures in both sexes

  2. Male Orgasm: Emission-Explusion-Ejaculation

  3. Female Orgasm: The uterus and outer vagina contract, but the inner two-thirds of the vagina do not
• Resolution Phase


  Completes the cycle and reverses the responses of the earlier stages