Plants 7 th grade

Types of Plants Common Traits:  Plants make their own food  Plant cells have cell walls outside of their cell membranes  Plants reproduce with a 2 part life cycle  produces spores – sporophyte  sex-cell producing phase – gametophyte

Types of Plants 2 main groups of plants 1. Nonvascular – have no vessels to transport materials through the plant (ex. mosses, liverworts) 2. Vascular – have vessels to transport materials through the plant

Vascular Plants Some do not produce seeds  ex. ferns, club moss  produce spores – small reproductive cell that can develop into adult without fusing to a cell

Vascular Plants plants that produce seeds  seeds, but not flowers – gymnosperms  reproduce seeds in flowers – angiosperms  annuals – plants that complete life cycle in 1 growing season and then die (corn, petunias)  biennials – plants that complete life cycle in 2 growing seasons  perennials - plants that live through many growing seasons and produce reproductive structures each year (trees)

Needs of Plants 1. Soil  Provides minerals and nutrients  Anchors the plant  Holds water around it  Contains humus – partially or totally decayed plants and animals  Best blend – sand, silt, clay and humus

Needs of Plants 2. Water  Necessary for photosynthesis  80% to 90% of plant’s weight 3. Sun  Helps manufacture food  Helps plants grow

Needs of Plants 4. Air  Clean air  Carbon dioxide in photosynthesis 5. Space to grow 6. Temperature

Nonvascular Plants  3 categories of nonvascular plants 1. mosses 2. liverworts 3. hornworts

Mosses and Liverworts  Lack sturdy stems  Small and grow close to the ground  Absorb water through diffusion and osmosis  Usually live in large groups  Parts:  Stem = Seta  Roots = Rhizoids  Leaves = Scales

Mosses and Liverworts Moss – has seta, reproduce sexually and asexually, contain no real roots  most familiar nonvascular plant  Fragmentation (asexual) – separation of a parent plant into parts that develop into whole new plants.

Ferns and their Allies Ferns:  leafy plant  grow in moist areas most of the year  need moisture to reproduce  have rhizomes – horizontal, underground stem  fronds – large divided leaves produced by rhizomes

Ferns and their Allies  Fiddleheads – young fronds that are tightly coiled and look like the end of a fiddle  Fern Allies – lack the stem and leaf structure of ferns but have life cycles of ferns. Ex. horsetails and club mosses  Epiphytes = plants that grow on other plants for support (club mosses)  All are helpful to the environment by forming soil and preventing soil erosion