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Chapter 8-1
Plants
• General Characteristics
Eukaryotes, multicellular, autotrophs
• Most live on land and need to
- obtain water/other materials from the soil through roots
- retain water, for example by the cuticle (waxy waterproof covering of
the leaf) that reduces water loss into the air
- transport materials by the vascular tissue, tube-like structures through
which food and water go down and up inside the plant
- be supported by the vascular tissue
- reproduce sexually involving fertilization, the process of joining of the
sperm and egg forming a zygote (the fertilized egg); the sperm needs
water to swim towards the egg
• Other adaptations
- petals that trap the sun to keep the plant warm
- plants that are not in the soil get nutrients/water by leaves that hug the
bark of a tree
- needles of some pine trees survive long periods of drought by growing
slowly at high altitudes away from disease-causing organisms
- long stems under water and roots anchoring the plants in mud at the
bottom of the pond
- huge root systems to trap soil/sand on which Mangrove trees can grow
- bad odor attracts insects for pollination
- long, narrow leaves to reduce water loss
- when growing in soil poor in nitrogen, plants get nitrogen by digesting
trapped insects (Venus Fly-Trap)
• Life Cycle – study Figure 3 on page 253.
Chapter 8-2
Non-vascular Plants
• General Characteristics
- no vascular tissue; get nutrients/water from soil by osmosis and
support by the cell wall
- live close to the water and are low-growing
• Moss – most diverse group
- structure: page 257
- importance:
~ in agriculture and gardening
~ peat moss makes soil better and is used as fuel for cooking/heating
~ mosses are “pioneer plants”
• Liverworts live on moist rocks and soil near streams, grow flat on the
ground
• Hornworts are slender, curved, and grow in moist soil.
Chapter 8-3
Seedless Vascular Plants
• General
- have vascular tissue
- use spores to reproduce
- live in moist places; water needed for sperm to swim to the egg
• Ferns
- range in size
- have true roots, stems, and leaves
the stems are mostly underground
the developing leaves are coiled and called fiddleheads; the
mature leaves are not curled and are called fronds
- reproduction
on the underside of fronds, spores develop in spore cases; they
are then released; the wind/water carry them away; if they land
in a suitable place they will develop into the gametophyte stage
and into tiny new plants
- importance
~ used as house plants
~ used to grow other plants such as orchids
~ the nonpoisonous ones can be eaten
~ some have bacteria in their leaves which produce a natural
fertilizer to help rice plants grow
• Club Moss
- found in moist woodland and near streams
• Horsetail
- stems are jointed and contain silica which was the reason the
plants were used to scrub pots and pans
Chapter 8-4
Feeding the World
New “high-tech” farming practices are used to produce plants that
• are insect-resistant
• are drought-resistant
• are disease-resistant
• produce more food
Genetic Engineering
- genetic material is altered
- adv.: plants can grow in different environments; plants that are
insect-resistant
Precision Farming
- satellite images and computers are used to know amount of
water and fertilizer needed
- adv.: saves time and money; more crops; prevents algal bloom
Hydroponics
- grow plants in a solution of nutrients instead of soil
- adv.: can grow plants in places with poor soil but it is costly