Syllabus Fall 2009

Plant Physiology BOT 4503 (3 cr).  Fulfills the Upper Division Section C requirement (Physiology/Biochemistry). Prerequisites: Organic Chemistry (2210) and General Biology I and II.  Web site: www.fiu.edu/~oberbaue/plantphysiology2009.htm.  Instructor: Steve Oberbauer HLS 218A PH:x2580 oberbaue@fiu.edu. Office Hours W 9-12 AM.

Text: Plant Physiology, Taiz and Zeigler, 4th Edition 2006

Time: MW 5-6:15  PC (Charles Perry) 447.

Month

Date

Topic

Readings

August

24

Course overview

Ch 1

26Enzymes and energeticsCh 2


31

Water and cells

Ch 3

 September

2

Plant water relations

Ch 4

7Labor day holiday, no classes

 

9

Water uptake and transport

Ch 4

 

14

Mineral nutrition

Ch 5

 

16

Solute transport, assimilation of minerals (see outlines at end)

Ch 6, 12

 

21

Respiration (see outlines at end of this web page)

Ch 11

 

23

Respiration continued (see outlines at end of this web page)

Ch 11

 

28

Photosynthesis (EXAM One  has been delayed until Wednesday)

Ch 7


30

Exam I 

 October

5

Photosynthesis

Ch 7, 8

 

7

Photosynthesis

Ch 8

 

12

Whole plant aspects of Ps

Ch 9

 

14

Phloem transport

Ch 10

 

19

Gene expression (http://4e.plantphys.net/)

Ch 14 (on web)

 

21

Growth and development

Ch 16

 

26

Phytochrome

Ch 17

 

28

Blue light responses

Ch 18

November

2

Exam II


 

4

Growth regulators (auxins)

Ch 19, 15

 

9

Growth regulators (gibberellins) 

Ch 20

11Veteran's day holiday, no classes

 

16

Growth regulators (cytokinins)

Ch 21

 

18

Growth regulators (ethylene) 

Ch 22

 

23

Growth regulators (abscissic acid, brassinosteroids)

 Ch 23,24

 

25

Written report work day

 

 

30

Control of Flowering (critiq

Ch 25

December

2

Seed germination

Ch 23

 

13

Final exam  (time slot not yet assigned)

 

Course Structure - Grading is based on two midterm exams and a final (short answer, brief essay, matching), and writing assignments (see below). The exams and final count for the majority of your grade (100 pts each) with each critique worth 15 pts (3 x 15 = 45) and proposed experiment worth 50 pts. This syllabus is subject to change without notice. Grading will generally be based on traditional 90, 80, 70, 60 percentage scale of total points. The course policy is that NO MAKE UP EXAMS WILL BE GIVEN. You are expected to be on time to exams. No student will be allowed to start taking the exam after any students have finished and left the room.

Leaning outcomes Students finishing this course will have fundamental understanding of plant photosynthesis, respiration, plant hormone control of growth and physiology, plant mineral nutrition, control of flowering and secondary compounds.

Important Academic Calendar dates:

August 29th Last day to drop courses or withdraw from the University without incurring a financial liability.

Aug 31. Last day to add a course, last day to change grading option,

Sept 18. Last day to withdraw with a 25% refund of tuition.

October 16th Last day to drop with a DR grade, last day to withdraw with a WI grade.

Course Policies - You are expected to be on time to class, and to stay the full period. You are expected to maintain high standards of academic honesty. Any student found in violation of these standards will earn an automatic F and be reported to the Deans Office, no exceptions made. In accordance with FIU's policy on academic honesty, as set forth in Section 2.44 of the Academic Affairs Policies and Procedures Manual (http://academic.fiu.edu/docs/aapolicies.htm), it is expected that students in Bot-4503 will not submit the academic work of another as their own. Additional discussion of academic honesty and integrity may be found in the Manual. 

Writing assignments
Objectives. The objectives of the writing assignments are to: 1) give you an opportunity to improve your grade if you do not do well on the exams, and 2) give you some writing practice and 3) get you into the primary plant physiological literature.

What you need to do.

1)  Choose a topic from the list provided or any other plant physiological topic.  Email your chosen topic to me.   I will provide you feedback as to the suitability of the topic.  It definitely needs to be plant physiological.  For example, if you wonder why certain bromeliads grow only on certain tree species, you would need to consider the physiological basis for germination on various substrates or inhibition of root growth etc.

2)  Find THREE recent research papers on the SAME topic (recent meaning in the last 5 years, nothing from before 2004, and from the research literature, not the newspaper or some other popular article).  On the next page I have provided a list of journals that typically carry plant physiological articles. 

3) Write a 1-page critique of each article (we will do this once for an article as a class to provide guidance and I will provide a series of questions that you will answer about the article to guide your critique).  Include the article with your critique.

4)  In a 3 page document of your own original writing, design an experiment to further advance the science of your chosen topic.  You may think that you do not know enough or are not creative enough to design a cutting edge experiment, but you WILL know enough after reading these papers and you are definitely creative enough.  Many undergraduates are designing, conducting, and publishing research throughout the U.S.  It sounds hard, but many papers often propose the direction for future research in their Discussion.  The 3 page experimental description should include: the background context, what your hypothesis is, what methods you will use, and what you expect to find.  You will need to cite research references for your chosen methods and the general context that will go on a separate page after the three pages of your description of what you are proposing to do.

Critique documents should be single-spaced typed (12 point Times Roman font) plus a cover sheet with your name and the full citation of the paper.

The experiment document should be a total of 5 pages, a cover sheet with your name and title of what you propose, 3 pages of the experiment as described above (single-spaced typed 12 point Times Roman font) and 1 of references (more if necessary).

In total, I am looking at 3 one-page critiques, and one 3 page experiment description with their cover sheets.  (More is ok, less would require seriously clear and concise writing on your part).  I will need the documents in both paper and electronic format

Important dates:


1) October 14th – your topic should be chosen
2) Oct 21st Critique 1 due
3) Oct 28th Critique 2 due
4) Nov 4th Critique 3 due
2) Final report due Nov 30th, 5 PM.

If you need help /guidance I will be happy to help with the design and look over drafts of your materials, but only if I see them at least one week before the due date.

** I have to put this in**.

Finally, all students have agreed to abide by the University Honor code, which prohibits copying text from other sources including the Web and claiming it as their own.  Also know that software specifically exists that is designed to find such plagiarized text for teachers.  Students caught plagiarizing will be subject to strong measures that may result in failure of the class or more serious consequences.

Example topics for experiments
control of fermentation pathways.
effects of low temperature on stomatal conductance
effects of severe water stress on CAM plants
effects of water stress on photosynthesis- direct or indirect?
Functional role(s) of the alternate oxidase
importance of hydraulic conductivity (stem resistance) on water transport
mechanism of water splitting in photosynthesis
mechanism of water uptake in plants ?
Mitochondrial activity during the daytime
photorespiration in C4 plants- how much if any?
physiology of C3-C4 intermediates
physiology of guard cells- do they carry out all of photosynthetic pathways?
the z scheme, is it dead?


Journals
Plant Physiology
International Journal of Plant Science
Journal of Experimental Botany
Physiologia Plantarum (electronic)
Planta
Tree Physiology
Functional Plant Biology (formerly Australian Journal of Plant Physiology)
American Journal of Botany
There are quite a few more and many journals publish a few articles each issue but only in special sections (such as does American Journal of Botany).


Lecture Outlines

Enzymes and energetics

Enzymes - biological catalysts

Gibbs Free energy

Activation energies of reactions

Factors affecting rates of reactions

How to make endergonic reactions proceed

names of enzymes

Reversible reactions

Enzyme function

Cofactors, prosthetic groups and metal ion activators

Isozymes

regulation of enzyme activity

external factors that affect enzyme activity

enyzme kinetics

Michaelis Menton

Lineweaver burke

Vmax, km

Inhibitors

Allosteric interactions - feedback and activating

Water and plant cells

Importance of water for plant cells and water's roles in plant function

properties of water

water availability and plant and ecosystem production

the big picture

Water potential and free energy

Components of water potential

water movement

bulk flow

diffusion

osmotic potential

turgor or pressure potential

gravitational potential

 

Plant water relations

water movement in model systems


Hofler diagrams. how plants adjust turgor in response to changes in water content

Matrix potential - a mythical component

How to measure water potential

How does water move in plants

Water uptake and transport

The tension cohesion theory
    driving force
    adhesion
    cohesion

plants are just a resistor in between soil and atmosphere

Cavitation

diurnal patterns of Psi and transpiration

Water uptake from roots

Root pressure

guttation

soil properties
    texture
    structure

soil water holding capacity

soil water potential

Transpiration

adaptations to minimize water loss

stomata as ultimate regulators of transpiration

Mechanism of stomatal opening

Mineral nutrition

Foliar absorption

mycorrhizae sources of nutrient inputs

Hoaglands macro and micronutrients

roles that nutrients fulfill

Fertilizers

how to test for nutrient requirements

Chelating agents to insure availability

Mineral content of the soil

cations

anions

pH effects on ion availability

accumulators

Ion uptake

 

Mineral nutrition II

Solute transport (ion transport in roots)

Nitrogen

forms of nitrogen for plant use

nitrate reductase

sources of nitrogen

the nitrogen cycle

nitrogen fixation

sources of biologically fixed N

The legume Rhizobium symbiosis

cyanobacteria

Analyzing nitrogen fixation

Elements and their major uses, mobility

Phosphorus

Potassium

Sulfur

Magnesium

Calcium

Iron

Copper

Manganese

Zinc

Molybdenum

Chlorine

Sodium

Respiration

RESPIRATION

Growth and maintenance respiration

Three main pathways of respiration

Localization of the pathways

Glycolysis

What you need to know about respiration

Fermentation

Energy yield of glycolysis

Oxidation of pyruvate

 

KREBS CYCLE

High energy compounds produced NADH, ATP, FADH2

Electron transport system

Membranes and pathways

Membrane fluidity

Four main complexes of Electron transport

Oxidation of NADH

Chemiosmosis

Coupling factors and ATP ase

Uncouplers

Energy yield

Cyanide resistant respiration

Function of cyanide resistant respiration

Hexose monophosphate shunt (Pentose shunt)

 

Photosynthesis

Overall reaction

water splitting versus splitting CO2

Light reactions and light independent reactions

Hill Reaction - photosynthetic reducing power of chloroplasts

Chloroplast structure and localization of reactions

Properties of light

Electron excitation

Deexcitation

Photosynthetic pigments

Light reactions

Two photosystems

Light harvesting complexes

Z scheme

Water splitting

Photophosphorylation

Quantum yield

Cyclic phosphorylation

Inhibitors of photosynthetic light harvesting

Localization of photosystems

Carbon fixation

Calvin Benson cycle

Regulation of Calvin cycle

Thioredoxin activation

Warburg effect

Photorespiration

Function of photorespiration

Bicarbonate pumps

C4 pathway

 

Whole plant aspects of photosynthesis

guiding principles

Plants have high photosynthesis in high resource environments

Plants can acclimate

Factors affecting photosynthesis

light

 

nutrients

 

CO2 concentration

 

plant water status

 

temperature

 

sink strength

 

Phloem Translocation

Sources and sinks

Phloem

Components of xylem and phloem sap

Mechanism of movement in phloem

Munch mass flow

Problems with mass flow

Multidirectional flow
differential rates of transport

P proteins

                                                      Gene Expression and Signal Transduction

Central dogma of molecular biology
DNA ---> mRNA ------> protein

plants have post-translational modification of mRNA

How to approach study of particular gene or genes activated in response to some treatment or condition

Example auxin stimulation of new protein synthesis

Making cDNA

Inserting DNA into bacteria & cloning it

Selecting the genes in clones
1) antibodies - Western blot
2) DNA hydridization - using probe if sequence is known
3) probes based on similar genes from other species
4) transposons

What can you do with gene once identified
a) transfer to another species
b) analyze when and where genes are expressed

How to transfer to other species
1) Agrobacterium tumefaciens
2) virus
3) naked DNA
4) microprojectile

How do you know your plant has the gene
1) add selectable gene
2) reporter genes

Expression of insert gene
inserted promoters

examples in plants:
luciferase
herbicides
antisense RNA

 

#Growth and development

Growth can mean different things

cell expansion, cell division, cell differentiation

How do plants grow - at meristematic tissues

types of plant growth - determinant, indeterminant

phases of growth - vegetative and reproductive

juvenility - heteroblastic development

differentiation

Totipotency

plant growth and development is controlled by plant growth substances (hormones)

plant growth regulators

5 classes of widely recognized plant growth substances

1) auxins

2) gibberelins

3) cytokinins

4) abscisic acid

5) ethylene

6) others - brassinosteroids

Approaches to analyze the mechanism of action of a plant growth substances

 

 

#LIGHT EFFECTS ON PLANTS-PHOTOMORPHOGENESIS

promotion of leaf expansion and leaf rolling

inhibits stem elongation

promotes root development

promotes branching and tillering

sets timing of sleep movements

promotes chlorophyll synthesis and accessory pigments

promotes seed germination -Light response is red/farred response

controlled by phytochrome - a tetrapyrole chromophore

phytochrome effect may have temperature and moisture interactions

Why a red light requirement
1) photosynthesis
2) spread out timing of germination
3) canopy sensing mechanism

phytochrome responses
very low fluence responses
low fluence responses
High irradiance responses

phytochrome forms and genetics

 

Blue Light responses

action spectrum has characteristic 3 finger structure

blue
inhibition of stem elongation

phototropism

stimulation of stomatal opening

blue light receptors (cryptochrome)

flavin?

carotenoid?

zeaxanthin?

signal transduction

 

Auxins

modes of auxin action


Darwin coleoptile experiments

isolation of auxin

chemistry of auxin

auxin induced cell elongation

Acid growth hypothesis

Auxin and root production

Auxin and apical dominance

auxin sensitivities of different tissues

Auxin transport

Auxin balance within the plant

mechanism of action

 

Gibberellins

discovery

isolation

physiological effects of gibberellins

elongation

juvenility

flowering in rosette plants

fruit set

seed dormancy

barley aleurone system

synthesis

transport

Cytokinins

division factor

bioassays

physiological effects

 

cell division

senescence

bud development

cell expansion

chloroplast development

auxin to cytokinin ratio

synthesis –

transport

Abscisic acid

abscisin and dormin

physiological effects

senescence

chlorophyll loss

dormancy

gibberellin interaction

desiccation tolerance

seed storage proteins

stomatal closure

inhibition of cell wall growth

hydraulic conductivity

synthesis

transport

mechanism of action

Ethylene

it’s a gas

fruit ripening and respiration rate

commercial uses

effects on seedling development

effect on cell expansion

interaction with auxin

ethylene transport

site of synthesis

ethylene synthesis

 

Brassinosteroids

Identified in 1970’s only recently widely accepted as a broad class of hormones

bioassays- bean stem, rice leaf bending

multiple active forms in plants

synthesized throughout plants

moves in xylem when externally applied

effects

         tissue differentiation

         cell expansion

         lateral root production

         xylem differentiation

         pollen tube growth

         seed germination

 

Control of Flowering

photoperiodism

Garner and Allard using Maryland Mammoth identified photoperiod control of flowering

photoperiod is phytochrome effect

short day plants
long day plants
day neutral plants

intermediates
longday-short day
short day long day

ecotypic variation in photoperiod

Time required to trigger response

Nature of the daylength response- the period of uninterrupted darkness is what counts.

Detecting the signal

signal transport

Florigen concept

Other factors important for flowering

1) age of plant

2) temperature

3) vernalization

4) water, carbon nutrient status

 

Seed germination

Seed properties

How long seeds retain viability

seed germination process

Conditions required for seed germination

1) temperature- heat and cold treatment

2) scarification

3) removal of inhibitors

4) light