vegetative parts. the main vegetative organs of plants that we will be talking about are roots stems...
TRANSCRIPT
Crown (leaf area)Captures sunlight and carbon dioxide (for photosynthesis) , regulates water loss (transpiration), has reproduction organs and produces seeds.
Respiration is the burning of nutrients for energy by the cells
Note: sugar.
All parts of plant carry on respiration
Epidermis
• Protects the leaf surface
• It is the “skin” of the leaf
• Holds in moisture also
• Upper and lower
Mesophyll
• Cells with chloroplasts filled with chlorophyll that carry out photosynthesis– Palisade cells are long, upright, erect, and
packed like sardines. Most photosynthesis takes place here.
– Spongy cells are rounded and irregular and loosely packed with a lot of air spaces for movement of gases. Less photosynthesis here because there are fewer chloroplasts.
Veins
• Bundles of vascular tissue– Xylem carrying water and nutrients to leaf
cells– Phloem carrying food to storage sinks– Sheathing cells to enclose and protect the
vascular tissue
Trunk, (stem)Transports water, food and other essential elements, stores energy, elevates and displays leaves to sun
(monocot)
Woody
(Dicot)
Herbaceous
In woody stems, the vascular cambium produces phloem on the outside (next to the bark) and xylem on the inside. Old xylem is the “wood” and exhibits the annual rings of growth
Roots1. 95% of roots in top foot of soil.
2. Biggest limiting factor to root growth is oxygen.
3. Roots often extend three times the distance of the branches.
Water is absorbed by diffusion into the root hairs then to the xylem of the root. It is then moved by cohesion of water molecules and capillary action up the stem xylem
Ideal SoilA) mineral material 45%
B) air 25%
C) water 25%
D) organic material 5%
note:
air + water = pore space
or
25% + 25% = 50% pore space
StressStress occurs often occurs when a plant won't get enough of what it needs. . .
Sunlight, water, essential elements, oxygen to roots etc.