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• People get food, raw materials, and medicines from plants
• Asexual reproduction


  Requires only one parent, produces new individuals without the fusion of gametes, genetically identical to the parent plants and each other, except when mutations occur
• Natural vegetative reproduction in plants


  • Stem (runners/stolons, rhizomes, tubers, bulbs, corms)
  • Leaves
  • Suckers or sprouts
  • Root fragments
• Artificial plant propagation


  Reproduction with a little help from humans
• Artificial plant propagation methods


  • Cutting
  • Grafting
  • Tissue culture
• Sexual reproduction


  Requires two parents, produces offspring by the fusion of gametes, offspring is genetically different from the parent or parents
• Flowers are the specialized reproductive structures of angiosperms, develop at the tips of reproductive shoots
• Parts of a flower


  • Calyx (sepals)
  • Corolla (petals)
  • Stamens (male reproductive part)
  • Carpels/Pistil (female reproductive part)

  
• Pollination


  The arrival of pollen on a receptive stigma
• Pollination vector


  Environmental agent that transfers pollen grains from one plant to another
• Pollinator


  Animal pollination vectors such as insects or birds
• Nectar


  Sweet fluid that rewards pollinators
• Sporophyte


  Diploid, spore-producing plant body, dominating the life cycle
• Gametophyte


  Haploid, gamete-producing structure
• Megaspore


  Haploid spore that gives rise to an egg-producing gametophyte
• Microspore


  Haploid spore that gives rise to a pollen grain
• Double fertilization


  One sperm cell fuses with the egg and forms diploid zygote, second sperm cell fuses with endosperm mother cell and forms a triploid cell which gives rise to endosperm (nutritive tissue in seeds of flowering plants)
• Seed


  A mature ovule that consists of an embryo sporophyte, its food reserves, and a seed coat (protective covering)
• Fruit


  Mature ovary of a flowering plant, often with accessory parts; encloses a seed or seeds
• Classification of fruits


  • Tissue composition (true fruit, accessory fruit)
  • Fruit origin (simple fruit, aggregate fruit, multiple fruit)
  • Dry or fleshy (dehiscent, indehiscent, drupe, berry, pepo, hesperidium, pome)
• Asexual reproduction of animals


  • Budding
  • Fragmentation
  • Binary fission
  • Parthenogenesis
• Hermaphrodites


  Sexually reproducing animals that can make both eggs and sperm

  
• Sequential hermaphroditism


  Some fishes switch from one sex to another over the course of a lifetime
• External fertilization


  Occurs in aquatic invertebrates, bony fishes, and amphibians, eggs and sperm released into the water, where fertilization occurs
• Internal fertilization


  Sperm fertilize an egg inside the female's body, occurs in cartilaginous fishes and most land animals

  
• Reproductive strategies with internal fertilization


  • Oviparous (egg-laying)
  • Ovoviviparous (eggs retained and embryo develops within mother's body)
  • Viviparous (young develop within mother's body and get nourishment directly from mother's blood)

  
• Embryo nourishment


  Embryos of most animals nourished by yolk, placental mammals produce yolkless eggs and nourish embryos through a placenta
• Gonads


  Specialized reproductive organs where gametes develop, eggs produced in ovaries, sperm produced in testes

  
• Oogenesis


  Process of egg formation
• Spermatogenesis


  Process of sperm formation

  
• Female reproductive system


  • Ovary
  • Oviduct/Fallopian tube
  • Uterus
  • Vagina
  • Vulva
• Egg production and release


  All production of oocytes occurs before birth, human females born with about 2 million oocytes, a human female ovary will release about 400 eggs in her lifetime, oocytes begin maturing at puberty, one at a time, in a 28-day cycle
• Menstrual cycle


  Hormones governing the cycle (GnRH, FSH, LH), once eggs have been fertilized, it prevents menstruation from occurring
• Premenstrual syndrome (PMS)


  Recurrence of symptoms caused by cycle-associated hormonal changes
• Menopause


  Occurs when all follicles in ovaries have been released or have disintegrated as a result of aging, follicles are depleted, menstrual cycles cease
• Male reproductive system


  Penis, seminiferous tubules (where sperm cells are produced)
• Luteinizing hormone (LH)


  Triggers the ovulation, stimulates formation of the corpus luteum
• Corpus luteum


  Prevents menstruation from occurring once the eggs have been fertilized
• PMS symptoms


  • Irritability
  • Depression
  • Headaches
  • Anxiety
  • Insomnia
• Menopause


  • Occurs when all follicles in ovaries have been released or have disintegrated as a result of aging
  • Follicles are depleted
  • Menstrual cycles cease
  • Occurs only in humans and two species of whales