Transcript Land Plants vs. Aquatic Plants

Land Plants vs. Aquatic Plants
Land Plants
• Vascular
– They have “veins” that transport nutrients
between leaves, roots, stems
– The veins are actually vascular tissue called
xylem and phloem
Veins that carry
water/nutrients
• Xylem: carries water from roots to other
parts of the plant
• Phloem: carries sugar and nutrients from
leaves to the rest of the plant
– Why would sugar come from leaves?
• Photosynthesis takes place mostly in leaves
• (Photosynthesis uses sun and CO2 to make sugar
and O2)
carbon dioxide
water
sugar
oxygen
Parts of a Plant
leaf
fruit
flower
seed
stem
roots
Leaves
• Main photosynthetic organ (why?)
– Collects the most sunlight
cuticle
upper epidermis
palisade cells
lignin
xylem
phloem
lower epidermis
spongy cells
guard cell
stoma
Flowers/Fruits/Seeds
• reproductive organs
• flower petals are modified leaves that
attract pollinators
• hold seeds
• dispersed to help the plant grow in new
places
Stem/Roots
• the stem holds up
and support the
plant; it also has
vascular bundles of
xylem and phloem
• roots anchor the
plant in the ground
and absorb water
and nutrients from
the ground
• What is the most
important thing for a
plant? light
• Where would be the
best place in the ocean
for plants and other
photosynthetic
organisms to be?
near the surface
Zones
• Because light is so
important to life, the
ocean is separated in
zones based on the
amount of light that
penetrates to that
depth
• photic means light
• eu means good
• dis means poor
• a means no
Aquatic Plants
• What do you think are some advantages
and disadvantages to living in or near
freshwater and saltwater?
Seagrasses
• evolved from land plants
• horizontal stems called
rhizomes
• very small flowers because…
• they don’t need to
attract pollinators
• why not?
Salt Marsh
• A salt marsh is an area that is partially
flooded at high tide
Salt-Marsh Plants
• Cordgrasses (halophytes- salt tolerant plants)
– actually in grass family unlike seagrasses
– not marine; just tolerant of salt
– help protect
areas from
erosion
– provide habitat
and breeding
grounds
– only get covered
by salt water at
high tides
– salt glands in
leaves excrete salt
salt excreting from leaves
Mangroves
• trees and shrubs that live on shores
• land plants tolerant of salt
• create mangrove forests
• thick leaves to reduce water loss; also
excrete salt
•seeds
grow for a
little while
on parent
then drop
into the
sediment
below
Pneumatophores
• specialized root extensions to help mangroves get extra
oxygen because the mud they grow in doesn’t have
enough
• mangrove roots beneath water provide
shelter for many types of organisms