BS 101 PLANT CELLS

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BS 101PLANT CELLS

• The Typical Plant Cell - ultrastructure
  differences between plant and animal cells
  vacuoles, plastids and plant cell walls.
• Plant Cell Growth and Development - apical
  meristems, cell division, expansion and
  differentiation.
• Plant Cell Culture - intro. to in vitro
  procedures and applications secondary metabolite
  production protoplast technology.

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Plant and animal cells
Chloroplast
Cell wall
Endoplasmic reticulum
Vacuole
Cytoplasm
Nucleus
Plasmalemma
Vacuole
Centriole/ centrosome
Peroxisomes
Golgi apparatus
Cytoskeleton
Mitochondrion (1 um long)
Secretory vesicles
Lysosomes
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Plant vs animal cells

• Plants have
• Vacuoles
• Plastids
• Cell walls

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Vacuoles

• Storage
• Turgidity
• Osmoregulation (water balance)

Tonoplast
Tonoplast membrane
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Plastids
Proplastids Original form in gametes and from
which all other plastids develop Leucoplasts Foo
d storage in non-photosynthetic
tissues Chromoplasts Store pigments (other than
photosynthetic ones)
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Chloroplasts

• Functions
• photosynthesis
• starch storage
• cytoplasmic inheritance

( 5 um long)
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Plant cell walls

• Functions
• strength
• rigidity
• protection

Plasmalemma
Cell wall (0.2 um thick)
Middle lamella
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Primary (undifferentiated) plant cell walls

• Cellulose (forms meshwork)
• Pectins (fill matrix)
• Hemicelluloses (fill matrix)
• Plasmodesmata (pores) - for cell-to-cell
  communication - grouped into primary pit fields

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Secondary (differentiated) plant cell walls

• Additional matrix substances
• Lignin
• Suberin
• Cutin
• Additional structure
• Pits (formed from primary pit fields)