05-10-2012, 05:01 PM
Parts of the plant and their functions
plant parts.ppt (Size: 177 KB / Downloads: 68)
Importance of plants
Without plants life on earth would not exist
Plants:
Primary source of food for people and animals
Produce oxygen
help to keep us cool
renew the air
slow wind speed
provide a home for wildlife
beautify surroundings
perfume the air
furnish building materials and fuel
Parts of a plant
Four basic parts
leaves
stems
roots
flowers
Leaves
the food factory of the plant
produce the food used by the plant or stored for later use
Leaf arrangement
alternate
opposite
whorled
arranged in a circle around the stem
External leaf structure
petiole - leaf stalk
leaf blade (leaf)
has veins
forms structural framework of the leaf
Internal leaf structure
allow the plant to breathe and transpire
give off moisture
Photosynthesis
process by which CO2 and H2O in the presence of light are converted to sugar and oxygen
food
manufactured in the leaves moves downward through the stem to the roots
used by the plant
stored in stem or root and leaf in the form of sugar, starch or protein.
Respiration
plants respire 24 hours a day
consume O2 and give off CO2
plants produce more O2 through ps. Than they consume during respiration and growth.
Internal Stem Structure
phloem- bark, carries manufactured foods down.
Xylem- wood, carries water and minerals up.
Cambium- separates the 2 and produces all new cells.
Characteristic of dicots