Download Transpiration - Don`t Trust Atoms

Starter
How are the following tissues adapted for their
function?
Tissue
Epidermal
Palisade Mesophyll
Spongy Mesophyll
Function
Adaptation
Transportation In Plants
• The roots, stem, and leaves form a plant
organ system for the transport of substances
around the plant.
Vascular Tissues: Phloem and Xylem
Read pg. 85 and make a note of the similarities
and differences between xylem and phloem.
Phloem
Type of Cell
Between Cells
(Type of End Walls)
Materials Transported
Direction of Transport
Name of transport
process
Diagram
Xylem
Phloem
Xylem
Type of Cell
Elongated living cells
Between Cells
(Type of End Walls)
End walls with small
pores
Dead cells
strengthened with
lignin
No end walls
Materials Transported
Dissolved food
substances (sugars)
Both directions
Water and minerals
translocation
Transpiration stream
Direction of Transport
Name of transport
process
Diagram
Upwards (root to
stem and leaves)
Transpiration
• Transpiration = loss of water from a plant
• Transpiration stream = movement of water
from the roots to the leaves
• Why does this happen?
Like sucking liquid
through a straw!
Water evaporates and diffuses out
(mainly through stomata)
Creates a shortage of water, more
water is drawn up through the xylem
More water is drawn up through the
roots creating a constant stream
Roots
• Function: absorption
of water (by osmosis)
and mineral ions (by
active transport).
• Adaptations: contain
root hair cells that
create a larger surface
area and speeds up
osmosis and active
transport.
Factors Affecting Transpiration
• Explain how each of these factors affect the
rate (speed) of transpiration. (pg. 87)
– Light intensity
– Temperature
– Air flow
– Humidity
Role of Stomata
(Review)
stoma
• Stomata allow gases
to diffuse into (and
out) of the leaf.
• Guard cells control
the size of the
stomata and control
water loss (through
evaporation and
diffusion).
guard
cells
Investigating Transpiration Rate
• A potometer can be used to measure the rate
of transpiration.
Calculating Rate of Transpiration
Rate of transpiration =
𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑎𝑖𝑟 𝑏𝑢𝑏𝑏𝑙𝑒 𝑚𝑜𝑣𝑒𝑑
𝑡𝑖𝑚𝑒
Homework
• Answer the exam style questions on pg. 93-94.