Download Unit 1 - Section 3.2 Plants

Grade 11 University Biology – Unit 1 Diversity of Life
Plant Kingdom
Section 3.2 (Pages 96-104)
Plants are organized by several characteristics.
Non-vascular Plants: Bryophytes
 Bryophyte – A small, non-vascular land plant (…non-vascular means
lacking xylem and phloem)
 Three phyla: (1) mosses, (2) liverworts and (3) hornworts
 See Table 3.1 on Page 96
 Transport of water and nutrients achieved by osmosis and diffusion,
respectively
 Typically, grow in mater of low, tangled mats of vegetation to hold water
(…able to survive dry and cold periods)
 Non-vascular and no roots; rather, root-like structures called rhizoids
 Usually no flowers
 Alternation of Germination life cycle (see Figure 3.9 on Page 97 and illustration “General Life
Cycle of a Moss”
opposite). Recall, the
sporophyte is 2n
diploid. After meiosis,
the gametes are
haploid n.
 The zygote is retained
in the female part of
the plant after
fertilization and grows
to become an embryo
 Since bryophytes lack
xylem and phloem,
some adaptations are
(1) one-cell thick leaflike structures and (2)
reside in wet areas
Seedless Vascular Plants
 Formed the first true forests on Earth about 350 MYA
 Vascular tissue allows plants to grow tall
 Sporophyte generation is longest part of life cycle. Sporophyes are also larger. Gametes are
short-lived, smaller and typically rely on water to transport haploid cells for sexual reproduction
 Four phylum: (1) whisk ferns, (2) club mosses, (3) horsetails and (4) ferns
 See Figure 3.10 “Fern Life Cycle” on Page 99
Seed-producing Vascular Plants (Gymnosperms and Angiosperms)
 First appeared 280 MYA
 Seeds reproduce sexually without water, provide protection from harsh conditions and survive for
long periods with no water
Gymnosperm
 Vascular plant with
non-enclosed seeds.
Includes cone-bearing
trees such as pines
and cedars, as well as
ginkgophytes. Most
are evergreen, and
thus, can
photosynthesis
whenever conditions
are suitable.
Reproduce sexually
by pollen grains.
Reproductive
structures are cones.
Male cones are small,
soft and short-lived;
whereas, female
cones are hard,
longer-lasting and
contain scales on which the eggs develop. Many pollen grains are produced and moved by wind
to land randomly on female cones.
Angiosperm
 Vascular plant with seeds enclosed in protective tissue
 First appeared 150 MYA
 About 90% of all plants
 Commonly referred to as flowering plants and includes such flowers as roses and trilliums, trees
such as maples and oaks, and grasses and weeds
 Reproduce using flowers. Flower is specialized. Flower usually
holds both female (pistil) and male (stamen) parts (see Figure 3.14
on Page 102). Male gamete is a pollen grain containing sperm
nuclei.
 Many ways to move pollen including wind and insect
 Fruit, a mature ovary of a flower that protects and disperses
dormant seeds. Many different dispersion adaptations including
animal ingestion, burrs and water.
 Two different groups bases on the structure of the seed leaf plus
other
features such
as monocots
with flowers
in multiples
of three
versus dicots have flowers in multiples of
four or five (see Table 3.3 Page 103) –
 Monocot – one cotyledon.
Example is corn
 Dicot – t wo cotyledons. Example
is maple tree
Questions
 Page 97, Questions 10-11
 Page 101, Questions 13-18
 Page 104, Questions 5, 8, 10, 12
Kingdom Plantae
Plant Kingdom
Non-vascular Plants
Vascular Plants
Seedless Plants
Plants with Seeds
Naked Seeds
Enclosed Seeds
Kingdom Plantae
Plant Kingdom
Eukaryotic, cell wall, cellulose, lack mobility,
autotrophic, seeds, sexual reproduction
Non-vascular Plants
Bryophytes – mosses
Moist environments (e.g., swamp)
Osmosis and diffusion to transport water and nutrients
Small (limited by no vascular tissue)
Rhizoids (root-like extensions)
Seedless Plants
Reproduce with spores (no seeds or flowers)
Four phylum (e.g., Pteridophyta – ferns)
Fronds
Naked Seeds
Gymnosperm
Evergreen (e.g., pine, spruce)
Needles (i.e., modified leaf)
Sexual Reproduction via pollen
Cones
Pollen distributed by wind
Vascular Plants
Tracheophytes
Support gained by vascular tissue (xylem and phloem)
Plants with Seeds
Spermatophytes
Roots, stems and leaves
Seeds with embryo
Enclosed Seeds
Angiosperms
Flowering Plants
Sexual Reproduction with flowers / seeds
Seed in fruit – Distributed by insect, wind, burr, etc.
Monocots and Dicots