Summary Plant Physiology - NWI-BB069B-2024-KW2-V 2024/2025
Plant physiology
This course is part of the Biology bachelor program at the Radboud University, Nijmegen, the
Netherlands and was followed in 2024-2025.
Course coordinator: Ivo Rieu
Lecturers: Eric Visser, Ivo Rieu
Departments in Plant and animal biology: system biology (modelling), stress biology (high
temperature e.g.), crop biotechnology
All information was gathered from the lecture slides (available on Brightspace) or from the book by
Taiz, L., Moller, I. M., Murphy, A., & Zeiger, E. (2018). Plant Physiology and Development (6
ed.), Oxford University Press, unless stated otherwise.
Table of content
Day 1 Water and transport ...................................................................................................................... 3
Water is essential for most plant functions ......................................................................................... 3
Transport ............................................................................................................................................. 3
Day 2 Nutrients ...................................................................................................................................... 12
Macronutrients .................................................................................................................................. 12
Micronutrients................................................................................................................................... 16
Cycles ................................................................................................................................................. 16
Culturing plants ................................................................................................................................. 17
Mobility ......................................................................................................................................... 17
pH .................................................................................................................................................. 17
Uptake in root ................................................................................................................................ 19
Transport towards cell ................................................................................................................... 19
Day 3 Photosynthesis............................................................................................................................. 21
Big level – Chloroplasts ...................................................................................................................... 21
Overview............................................................................................................................................ 21
Light ................................................................................................................................................... 22
Z-scheme ........................................................................................................................................... 23
Energy transfer .................................................................................................................................. 23
Excitation of photon .......................................................................................................................... 24
Oxygen evolving complex .................................................................................................................. 25
Proteins in between photosystem II and photosystem I ................................................................... 25
Damage due to excess of light ........................................................................................................... 27
1
,Summary Plant Physiology - NWI-BB069B-2024-KW2-V 2024/2025
Dark reaction – learn by heart! ......................................................................................................... 28
Starch and sucrose production .......................................................................................................... 29
Cell walls and growth ........................................................................................................................ 31
Day 4 - How does a plant get its shape?................................................................................................ 33
Patterning .......................................................................................................................................... 33
Auxin as a morphogen ....................................................................................................................... 34
Auxin signal transduction .................................................................................................................. 36
Auxin has two types of effects....................................................................................................... 37
Intermezzo: How to describe a signalling pathway? ......................................................................... 37
Questions in question hour ............................................................................................................... 38
Day 5: How does a plant grow? ............................................................................................................. 38
Meristematic growth – shoot apical meristem ................................................................................. 38
Balancing root and shoot growth ...................................................................................................... 40
Growth and auxin .............................................................................................................................. 41
Growth and gibberellin...................................................................................................................... 43
Day 6: How does a plant adapt its shape and growth to its environment? .......................................... 46
Light as a signal for development ...................................................................................................... 46
Photo- and gravitropism .................................................................................................................... 48
Stress inhibits growth - Salt in soil..................................................................................................... 49
Adaptation to flooding ...................................................................................................................... 50
2
,Summary Plant Physiology - NWI-BB069B-2024-KW2-V 2024/2025
Day 1 Water and transport
Water is essential for most plant functions
- Strength (turgor) and growth
- Solvent for substances, transport in xylem (water and nutrients) and phloem (carbohydrates)
and inside and between cells
- High consumption caused by loss of water during CO2 uptake
- Small decreases in water content lead to high stress level
-
Higher water availability = higher primary production
- (also depending on temperature)
- How? Water needed for stomata opening, needed for gas exchange
-
Transport
Why is water so suitable as a solvent and a transport medium?
3
, Summary Plant Physiology - NWI-BB069B-2024-KW2-V 2024/2025
- Physical properties of water are of key importance here
- High polarity:
o Ions and polar molecules dissolve easily
o H-bridges: adhesion and cohesion → transport
How is water transported in a plant?
- Water potential: potential energy of water, or its ability to perform mechanical work
-
- Water potential = osmotic potential + hydrostatic pressure + gravitational potential
- Water goes from high potential to lower
potential (or negative to more negative)
- In equilibrium, the total water potential
of a cell in a solution is equal to the
total water potential of the solution
without cell (Ψp = 0, and Ψs = -0.1 MPa,
so Ψ = -0.1MPa), so Ψ(cell in solution in
equilibrium) = -0.1MPa
- Ψs Osmotic potential: pressure
resulting from characteristics of water
to move from hypotonic to hypertonic
solutions: inside plant always Ψs <0, in
pure water =0. Depending on
o amount of dissolved particles n (higher = Ψs higher), 2x if salt!
o Volume of solution
o Temperature
o T in K, so little influence of 20 -
> 30C change
o Only Ψs changes, not Ψp and Ψg
4
Plant physiology
This course is part of the Biology bachelor program at the Radboud University, Nijmegen, the
Netherlands and was followed in 2024-2025.
Course coordinator: Ivo Rieu
Lecturers: Eric Visser, Ivo Rieu
Departments in Plant and animal biology: system biology (modelling), stress biology (high
temperature e.g.), crop biotechnology
All information was gathered from the lecture slides (available on Brightspace) or from the book by
Taiz, L., Moller, I. M., Murphy, A., & Zeiger, E. (2018). Plant Physiology and Development (6
ed.), Oxford University Press, unless stated otherwise.
Table of content
Day 1 Water and transport ...................................................................................................................... 3
Water is essential for most plant functions ......................................................................................... 3
Transport ............................................................................................................................................. 3
Day 2 Nutrients ...................................................................................................................................... 12
Macronutrients .................................................................................................................................. 12
Micronutrients................................................................................................................................... 16
Cycles ................................................................................................................................................. 16
Culturing plants ................................................................................................................................. 17
Mobility ......................................................................................................................................... 17
pH .................................................................................................................................................. 17
Uptake in root ................................................................................................................................ 19
Transport towards cell ................................................................................................................... 19
Day 3 Photosynthesis............................................................................................................................. 21
Big level – Chloroplasts ...................................................................................................................... 21
Overview............................................................................................................................................ 21
Light ................................................................................................................................................... 22
Z-scheme ........................................................................................................................................... 23
Energy transfer .................................................................................................................................. 23
Excitation of photon .......................................................................................................................... 24
Oxygen evolving complex .................................................................................................................. 25
Proteins in between photosystem II and photosystem I ................................................................... 25
Damage due to excess of light ........................................................................................................... 27
1
,Summary Plant Physiology - NWI-BB069B-2024-KW2-V 2024/2025
Dark reaction – learn by heart! ......................................................................................................... 28
Starch and sucrose production .......................................................................................................... 29
Cell walls and growth ........................................................................................................................ 31
Day 4 - How does a plant get its shape?................................................................................................ 33
Patterning .......................................................................................................................................... 33
Auxin as a morphogen ....................................................................................................................... 34
Auxin signal transduction .................................................................................................................. 36
Auxin has two types of effects....................................................................................................... 37
Intermezzo: How to describe a signalling pathway? ......................................................................... 37
Questions in question hour ............................................................................................................... 38
Day 5: How does a plant grow? ............................................................................................................. 38
Meristematic growth – shoot apical meristem ................................................................................. 38
Balancing root and shoot growth ...................................................................................................... 40
Growth and auxin .............................................................................................................................. 41
Growth and gibberellin...................................................................................................................... 43
Day 6: How does a plant adapt its shape and growth to its environment? .......................................... 46
Light as a signal for development ...................................................................................................... 46
Photo- and gravitropism .................................................................................................................... 48
Stress inhibits growth - Salt in soil..................................................................................................... 49
Adaptation to flooding ...................................................................................................................... 50
2
,Summary Plant Physiology - NWI-BB069B-2024-KW2-V 2024/2025
Day 1 Water and transport
Water is essential for most plant functions
- Strength (turgor) and growth
- Solvent for substances, transport in xylem (water and nutrients) and phloem (carbohydrates)
and inside and between cells
- High consumption caused by loss of water during CO2 uptake
- Small decreases in water content lead to high stress level
-
Higher water availability = higher primary production
- (also depending on temperature)
- How? Water needed for stomata opening, needed for gas exchange
-
Transport
Why is water so suitable as a solvent and a transport medium?
3
, Summary Plant Physiology - NWI-BB069B-2024-KW2-V 2024/2025
- Physical properties of water are of key importance here
- High polarity:
o Ions and polar molecules dissolve easily
o H-bridges: adhesion and cohesion → transport
How is water transported in a plant?
- Water potential: potential energy of water, or its ability to perform mechanical work
-
- Water potential = osmotic potential + hydrostatic pressure + gravitational potential
- Water goes from high potential to lower
potential (or negative to more negative)
- In equilibrium, the total water potential
of a cell in a solution is equal to the
total water potential of the solution
without cell (Ψp = 0, and Ψs = -0.1 MPa,
so Ψ = -0.1MPa), so Ψ(cell in solution in
equilibrium) = -0.1MPa
- Ψs Osmotic potential: pressure
resulting from characteristics of water
to move from hypotonic to hypertonic
solutions: inside plant always Ψs <0, in
pure water =0. Depending on
o amount of dissolved particles n (higher = Ψs higher), 2x if salt!
o Volume of solution
o Temperature
o T in K, so little influence of 20 -
> 30C change
o Only Ψs changes, not Ψp and Ψg
4
