• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Unit 22 Plant Lifecycles
 

Unit 22 Plant Lifecycles

on

  • 2,479 views

 

Statistics

Views

Total Views
2,479
Views on SlideShare
2,477
Embed Views
2

Actions

Likes
2
Downloads
116
Comments
1

2 Embeds 2

http://olympushighschool.blogspot.com 1
http://www.slideshare.net 1

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel

11 of 1 previous next

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
  • THANKS A LOT
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Unit 22 Plant Lifecycles Unit 22 Plant Lifecycles Presentation Transcript

    • KEY CONCEPTAll plants alternate between two phases in their life cycles.
    • SPOROPHYTE
      PHASE
      fertilization
      meiosis
      GAMETOPHYTE
      PHASE
      Plant life cycles alternate between producing spores and gametes.
      A two-phase life cycle is called alternation of generations.
      haploid phase
      diploid phase
      alternates betweenthe two
    • The spore-producing plant is the mature sporophyte.
      sporophyte phase is diploid
      begins with fertilized egg
      spores produced through meiosis
      The gamete-producing plant is the mature gametophyte.
      • gametophyte phase is haploid
      • begins with spore
      • gametes produced through mitosis
    • sporophyte (2n)
      capsule
      spores (1n)
      gametophyte (1n)
      Life cycle phases look different among various plant groups.
      Nonvascular plants have a dominant gametophyte phase.
      moss gametophytes look like green carpet
      moss sporophytes shoot up as stalklike structures
    • sporophyte (2n)
      sori
      The sporophyte is the dominant phase for seedless vascular plants.
      • Fern spores form in sacs, sori, on underside of mature sporophytes (fronds).
    • A fern gametophyte, or prothallus, produces sperm and eggs.
      gametophyte (1n))
      rhizoid
      • A zygote forms on the prothallus, growing into the sporophyte.
    • The sporophyte is the dominant phase for seed plants.
      pine trees are typical seed plant sporophytes
      female spores produced in female cones
      male spores produced in male cones
      male spores develop into pollen grains, the male gametophytes
      female spores develop into female gametophytes that produce eggs
      sperm from pollen travel down pollen tube toward egg
      fertilized egg develops into embryo
      ovule develops into protective pine seed
    • The sporophyte is the dominant phase for seed plants.
    • sepal
      Flowers contain reproductive organs protected by specialized leaves.
      Sepals and petals are modified leaves.
      Sepals are outermostlayer that protectsdeveloping flower
    • petal
      Petals can help to attract animal pollinators
    • stamen
      filament
      anther
      A stamen is the male structure of the flower.
      • anther produces pollen grains
      • filament supports the anther
    • stigma
      style
      carpel
      ovary
      The innermost layer of a flower is the female carpel.
      • stigma is sticky tip
      • style is tube leading from stigma to ovary
      • ovary produces female gametophyte
    • Flowering plants can be pollinated by wind or animals.
      Flowering plants pollinated when pollen grains land on stigma.
      Wind pollinated flowers have small flowers and large amounts of pollen.
      • Animal pollinated flowers have larger flowers and less pollen.
      many flowering plants pollinated by animal pollinators
      pollen grains
      • pollination occurs as animal feeds from flower to flower
      • animal pollination more efficient than wind pollination
    • Fertilization takes place within the flower.
      • Male gametophytes, or pollen grains, are produced in the anthers.
      • male spores produced inanthers by meiosis
      • each spore divides bymitosis to form twohaploid cells
      • two cells form asingle pollen grain
      pollen grain
      • One female gametophyte can form in each ovule of a flower’s ovary.
      four female spores produced in ovule by meiosis
      one spore develops into female gametophyte
      female gametophyte contains seven cells
      one cell has two nuclei, or polar nuclei
      one cell will develop into an egg
    • pollen tube
      sperm
      stigma
      Pollination occurs when a pollen grain lands on a stigma.
      • one cell from pollen grain forms pollen tube
      • other cell forms two sperm that travel down tube
    • female
      gametophyte
      egg
      sperm
      polar nuclei
      ovule
      Flowering plants go through the process of double fertilization.
    • endosperm
      seed coat
      embryo
      • Flowering plants go through the process of double fertilization.
      • one sperm fertilizes the egg
      • other sperm unites with polar nuclei, forming endosperm
      • endosperm provides food supply for embryo
    • Each ovule becomes a seed.
      • The surrounding ovary grows into a fruit.
    • Animals, wind, and water can spread seeds.
      • Seeds dispersed by animals can have nutritious fruits or fruits that cling.
    • Cypselae
      Double samaras
      • Seeds dispersed by wind can have wing- or parachute-like fruits.
    • Seeds begin to grow when environmental conditions are favorable.
      Seed dormancy is a state in which the embryo has stopped growing.
      • Dormancy may end when conditions are favorable.
      • While dormant, embryo can withstand extreme conditions.
    • Germination begins the growth of an embryo into a seedling.
      • water causes seed to swell and crack coat
      • embryonic root, radicle, is first to emerge
      • water activates enzymes that help send sugars to embryo
    • Germination begins the growth of an embryo into a seedling.
      water causes seed to swell and crack coat
      embryonic root, radicle, is first to emerge
      water activates enzymes that help send sugars to embryo
      • embryonic shoot, plumule, emerges next
    • Germination begins the growth of an embryo into a seedling.
      water causes seed to swell and crack coat
      embryonic root, radicle, is first to emerge
      water activates enzymes that help send sugars to embryo
      embryonic shoot, plumule, emerges next
      • leaves emerge last
    • Once photosynthesis begins, the plant is called a seedling.
    • Plants can reproduce asexually with stems, leaves, or roots.
      Asexual reproduction allows a plant to make copies of itself.
      Regeneration is one type of asexual reproduction.
      plants grow a new individual from fragment of parent
      occurs when piece of a stem, leaf, or root falls off parent plant
      • Vegetative reproduction is another type of asexual reproduction.
      stems, leaves, or roots attached to parent plant produce new individuals
      specific adaptations include stolons, rhizomes, and tubers
    • Humans can produce plants with desirable traits using vegetative structures.
      Vegetative propagation takes advantage of plants’ ability to reproduce asexually.
      Humans use one plant with desirable traits to produce many individuals.
      • cutting of leavesor stems may grow new roots
      • grafting joins the parts of two plants together to form a hybrid plant