BIOC40H3 Lecture Notes - Lecture 3: Middle Lamella, Dicotyledon, Lignin
Document Summary
As we discussed in the last lecture on water and plants, there is an inherent conflict between a plant"s need to take in co2 for photosynthesis and to conserve water. This is because both co2 and water must use the same pathway through stomates, with co2 going in, and water being lost out of the pores. We discussed the special properties of water last lecture, (most of them, dependent on the extensive hydrogen bonding in water molecules) Now we will look at many of the ways that plants have evolved adaptations to move water with in the plant, control water loss from leaves and to replace the water that is lost. Water potential ( ) of soils can be divided into three components: osmotic pressure ( , hydrostatic pressure ( , gravitational potential ( ) Since solute concentration in soil tends to be very low, the osmotic pressure ) is generally negligible.