lecture 16- plants Flashcards
characteristics of plants
non motile
terrestrial
multicellular
eukaryotic
have chloroplast and chlorophyll
cell wall made of cellulose
what are the ecological impacts of plants
reduce greenhouse gases and produce oxygen
provide cover for wildlife
are a food source (primary producers)
prevent soil erosion (hold water and soil while building soil)
how do plants prevent soil erosion
slows the fall of water down so it doesn’t hit ground as hard
roots act as nets to prevent soil movement
how does soil erosion lead to algae blooms
the water that washes drips through soil with wash away the nutrients, pesticides into water sources and can lead to algae blooms
what are the main groups of land plants
bryophytes (moss)
seedless vascular plants (ferns)
gymnosperms (conifers)
angiosperms (flowering plants)
characteristics of bryophytes
no true tissues or organs
no vascular system
small and compact
water fertilization (motile sperm)
live in moist environments
thickness of bryophytes
one cell layer thick because diffusion can’t get nutrients through thicker layers
what are the anchors of bryophytes
rhizoids (not quite roots)
what is the alternation of generation process of bryophytes
- water disperses the spores
- the spores germinate into plants (separate male and female plants)
- rain falls on male plant and picks up sperm
- water with sperm can encounter the female plant
- fertilization occurs = zygote
- the zygote grows in female plant which becomes a sporophyte then a sporangium
- sporangium releases spores
what is special about peat moss
its organic materials don’t decay fast
they release acidic secretions that prevent bacteria and fungi activity
what are some adaptations to life on land have plants gone through
waxy cuticle
stomata
tissues
seeds
what is a waxy cuticle
covers the epidermis
prevents dehydration
what are stomata
pores on the leafs surface to allow gas exchange
can open or close (partially or totally)
what are the types of vascular tissue
xylem and phloem
what does the xylem transport
water and inorganic nutrients (minerals)
what does the phloem carry
water and organic molecules
what are the uses of vascular tissue
transportation from roots to leaves and back
what are roots
anchors for the plants
characteristics of roots
used as storage
have root hairs for more surface area
take in nutrients and water
characteristics of stems
structural support for leaves
transport materials from roots to leaves
characteristics of leaves
photosynthesis site
flat thin leaves with waxy coat to reduce water loss
characteristics of seedless vascular plants
sperm is flagellated
have vascular tissue and plant organs
big plants
don’t have seeds, have spores
damp environments
alternation of generation for seedless vascular plants
- water disperses spores
- spores develop into gametophyte (plant that can produce gametes)
- gametophyte produces gametes
- sperm fertilizes egg
- egg becomes zygote
- zygote becomes sporophyte on top of gametophyte
- sporophyte produces sporangium which releases spores
characteristics of seeds
has multicellular embryo that has root stem and leaves already
has protective covering called seed coat
has stored food
