Non-vascular plants

• Characteristics of Kingdom Plantae

  • Multicellular

  • Eukaryotic

  • Autotrophic by photosynthesis

  • Alternation of generations reproductive cycle

  • Cell wall made of cellulose

  • Store starch in chloroplasts

  • Most plants have stems and leaves with a waxy

  waterproof coating called a cuticle
• • Scientists believe that plants evolved from ancestral

  green algae

  • Why?

  • Chlorophyll in chloroplasts

  • Cellulose in cell walls

  • Store food in the form of starch (long chains of glucose)

  • Have alternation of generations
• • In the beginning, plants lived exclusively in water

  • Advantages of living in the water included…

  1. Prevents drying out.

  2. Gives structural support (less affected by gravity)

  3. Provides nutrients and gas

  exchange by diffusion.

  4. Helps to disperse spores

  and the meeting of gametes.
• 1. Haploid

  – one set of genetic information

  – Symbol: n

  – Example: egg cell is haploid, sperm cell is haploid
• 2. Diploid

  – Two sets of genetic information

  – Symbol: 2n

  – Example: zygote – fusion of egg and sperm cell
• 1. Gametophyte

  • This structure is haploid (n)

  • Produces gametes – egg and sperm

  • When egg and sperm fuses together it will form a diploid zygote that

  grows into a sporophyte.
• 2. Sporophyte

  • This structure is diploid (2n)

  • Produces spores (n)

  • The spores will grow into a gametophyte

  • All plants will alternate and produce these two structures throughout the

  course of their life.
• Sporophyte is the dominant structure in higher plants

  (diploid stage: 2n)
• Sporophyte is the dominant structure in higher plants

  (diploid stage: 2n)
• Nonvascular

  • 3 of the 12 phyla

  • Lack vascular tissue to transport H2O and nutrients

  • Include mosses, liverworts, and hornworts
• Vascular

  • 9 of the 12 phyla

  • possess water & nutrient transporting system:

  1. Xylem - water

  2. Phloem - solution of nutrients

  • include ferns, conifers, and flowering plants
• Nonvascular Plants

  • Primitive land plants

  • Are photosynthetic

  • Cell wall made of cellulose

  • Lack vascular tissue( ex: missing “xylem” and “phloem” )

  (analogous to arteries/veins...)

  • Do NOT have true leaves, stems and roots

  • Are small – lack structural support by vascular tissues

  • Require water for fertilization

  • Asexual and sexual reproduction

  • Alternation of generations

  • Gametophyte generation is dominant

  • Mainly exist as a haploid individual
• 1. Phylum Bryophyta

  Plant Example - Mosses

  • Regarded as transitional between aquatic plants like

  algae and higher land plants like trees.

  • Without roots or vascular tissue, these plants remain

  small and must live in moist environments.

  • Water and food flows slowly from cell to cell

  through diffusion
• • Sporophyte (diploid generation)

  – structure grows out of the

  gametophyte and is a skinny stalk with

  a capsule full of spores at the top.
• • Gametophyte (haploid generation)

  – structure is the common green fuzzy

  moss.

  – Carries out photosynthesis
• • Rhizoids are root-like structures that

  anchor the moss.
• • Calyptra

  – Protective hood that covers

  the capsule
• • Capsule

  – Contains the spores where the

  spores will be released when

  conditions are right
• • Seta or Stalk

  – Help raise the spores for more

  effective dispersal
• • Protonema

  – Thread-like filaments that

  eventually develop into a

  gametophyte
• • Gametophyte is photosynthetic

  • It supplies water and nutrients to the sporophyte
• Sperm-producing structure

  called the antheridium

  Egg-producing structure

  called the archegonium1
• • Mosses are pioneer plants like lichens, growing on bare

  rock and contributing to soil development.

  • They are the first to grow in areas where a forest

  burned out or volcanoes erupted.
• • In forest ecosystems they act like a sponge retaining

  and slowly releasing water

  • They provide habitat for other plants and small animals

  as well as microorganisms
• • Bogs contain sphagnum moss.

  • Sphagnum can absorb many times its own weight in

  water - a natural sponge.
• • Bogs are swamps where sphagnum moss grows

  naturally.

  • Bog water can be very acidic that little bacteria

  can grow.

  • Therefore, mosses don’t decompose quickly when they

  die.
• • The mosses pile up at the bottom in a thick mat call

  peat.

  • Peat is mined for fuel and garden soil additive.
• 2. Phylum Hepaticophyta

  Plant Example - Liverworts

  • Shaped like a liver! (sort of..)

  • Hepar means liver

  • Sexual reproduction similar to mosses

  • Gametangia -umbrella like structures that contain the

  gametes (sperm or eggs)

  • Gametangia grows out of the sporophyte.
• 3. Phylum Anthocerophyta

  Plant Example - Hornworts

  • Only about 100 species

  • Smallest division of nonvascular plants

  • “Horn” refers to the tall narrow sporophytes which are

  embedded in the top of the plant.

  • The sporophyte remains attached to its parent

  gametophyte throughout life.