Lectures on Plant Physiology

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Lectures on Plant Physiology

• Prepared by
• Prof Mohammed Naguib Abdel-Ghany Haseneen
• Professor of Plant physiology

For Pre-Dental Students
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Contents

• Plant Cell
• Plant Cell structure and function
• Different Bio-Physico-Chemical Phenomena
• Colloids
• Diffusion
• Osmosis
• Imbibitions
• The Enzymes
• Structure
• Mode of action
• Inhibitors
• Factors affecting enzymatic activity

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Cont.

• Metabolism
• Respiration
• Glycolysis, TAC, Fermentation
• Factors affecting rate of respiration
• Amino acid and protein metabolism
• Biotechnology
• -What is biotechnology?
• Biotechnology benefit

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1- Plant Cell (Structure and Function)

• Cells are the basic unit of life.
• Cells carryout all the necessary functions for
  life such as reproduction, taking in nutrients
  and excreting wastes.
• Cells are made up of chemicals and molecules.
  Human cells contain mostly water.

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The Cell

• Cells are classified as prokaryotic and
  eukaryotic.
• Prokaryotic cells lack a well-defined nucleus and
  many organelles. Bacteria are prokaryotic cells.
  
• Eukaryotic cells include the protists, fungi,
  plant and animal cells. We will study these
  cells during this lab.

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The Cell

• Animal Cells
• Have centrioles
• Store glucose as glycogen
• Do not have a cell wall
• Contain mitochondria

• Plant Cells
• Lack centrioles
• Store glucose as cellulose or starch
• Have a cell wall
• Have large vacuoles
• Contain chloroplasts as well as mitochondria

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The Cell

• Animal Cell
• Click on the cell to study it in more detail

• Plant Cell
• Click on the cell to study it in more detail

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Animal CellClick on each organelle to learn its
function. When you have finished click on the
arrow button to study the plant cell.
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Plant CellClick on each organelle to study its
function. When you have finished click here to
study the animal cell or here to continue this
lab.
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Cell is a unit or module of plant organization

• Supports cells plant- Controls cell growth
  shape

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Cell Wall

• Only found in plant cells
• Surrounds cell membrane
• Composed of lignin and cellulose
• Function to strengthen and protect plant cells.

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Cell Wall

• Structural functions
• Provides rigidity to plant
• Determines size and shape of cell
• Determines size and shape of plant
• Other functions
• Absorption
• Transport
• Secretion
• Cell-cell communication

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Structure of cell wall

• Cellulose is principal component
• Repeated monomers of glucose attached end to end
• Bundled into microfibrils
• Crystalline properties
• Cellulose matrix is embedded in matrix of
  noncellulosic molecules
• Provide cross-links between cellulose
  microfibrils
• Pectins hydophilic polysaccharides
• Glycoproteins- extensins

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Structure of cell wall continued

• Primary wall
• Formed first while cells growing and dividing
• Enriched in pectins and water (to allow
  expansion)
• Middle lamella
• Joins adjacent cells
• Mostly pectins

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Cell wall structure continued

• Secondary wall
• Not all cells form
• Deposited after cell has stopped growing
• Inside primary wall
• More cellulose
• Pectins lacking
• Rigid
• Formed by cells that provide strength or
  transport

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Cell walls (yellow) separated by middle lamella
(black)
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(No Transcript)
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Middle lamella (black) separates walls from 2
different cells
Cell membrane contacts inner part of wall
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Cellulose is polymer of glucose that aggregates
into threads (microfibrils)
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Cellulose threads are woven in cell wall