University of Santo Tomas
Faculty of Pharmacy, BS Pharmacy Batch 2027
PHA611: Pharmaceutical Botany with Taxonomy (Laboratory)
Exercise 5: Plant Cell Division • Gene (portion of genome/DNA; polymer of nucleotides)
replication
CELL CYCLE
• Chromatin synthesis
Cell cycle: stages of initiation, growth, and death
• Endoreduplication: repeated cycles of DNA replication
• Young embryonic plant: all cells divide
causes nucleus to enlarge
• Root tips and shoots: center of cell division
o Occurs in 80% of maturing plant cells
o Occurs in cells with rapid intense metabolism (e.g.
Factors affecting cell cycle
hair, glandular cells)
• Cell type
• Gene replication: endoreduplication but only for
• Plant type
specific genes
• Health
• Age G2 (second gap/gap 2) phase
• Term • Growth and preparation for mitosis
• Begins after chromatid replication; 3–5 hours
CELL CYCLE ARREST • Production of alpha and beta tubulins for microtubules
Cell cycle arrest: cells stop diving and enter an extended period o Spindle microtubules aid in moving organelles
of growth during cell division
• E.g. leaf cells grow as leaf expands; cortex cells o Production of proteins for chromosome processing
(stem/root) stop dividing before organ matures and nuclear membrane breakdown
CELL GROWTH
• Alma Howard and S.R. Pelc determined DNA synthesis
occurrence in interphase and designated G1, S, and G2
phases
Interphase
• Resting phase
• Not part of mitotic process
• Slowest phase
• Chromatin is undifferentiated
G1 (first gap/gap 1) phase
• Growth and rapid biosynthesis
• Longest part of cell cycle CELL DIVISION
• Start of production of nucleotides Karyokinesis: nuclear division
• Arrested cellular activities during mitosis are
reactivated Mitosis
• Cell enlarges • Occurs in all multicellular plants and animals to permit
• Organelles multiply growth of the organism
• Mitochondrion DNA and plastids increase • 2N, diploid, somatic cells
• Not applicable for sex cells/gametes
S (synthesis) phase • Duplication division
• Growth and DNA replication/synthesis
1|P a g e
LIANRPh
Faculty of Pharmacy, BS Pharmacy Batch 2027
PHA611: Pharmaceutical Botany with Taxonomy (Laboratory)
Exercise 5: Plant Cell Division • Gene (portion of genome/DNA; polymer of nucleotides)
replication
CELL CYCLE
• Chromatin synthesis
Cell cycle: stages of initiation, growth, and death
• Endoreduplication: repeated cycles of DNA replication
• Young embryonic plant: all cells divide
causes nucleus to enlarge
• Root tips and shoots: center of cell division
o Occurs in 80% of maturing plant cells
o Occurs in cells with rapid intense metabolism (e.g.
Factors affecting cell cycle
hair, glandular cells)
• Cell type
• Gene replication: endoreduplication but only for
• Plant type
specific genes
• Health
• Age G2 (second gap/gap 2) phase
• Term • Growth and preparation for mitosis
• Begins after chromatid replication; 3–5 hours
CELL CYCLE ARREST • Production of alpha and beta tubulins for microtubules
Cell cycle arrest: cells stop diving and enter an extended period o Spindle microtubules aid in moving organelles
of growth during cell division
• E.g. leaf cells grow as leaf expands; cortex cells o Production of proteins for chromosome processing
(stem/root) stop dividing before organ matures and nuclear membrane breakdown
CELL GROWTH
• Alma Howard and S.R. Pelc determined DNA synthesis
occurrence in interphase and designated G1, S, and G2
phases
Interphase
• Resting phase
• Not part of mitotic process
• Slowest phase
• Chromatin is undifferentiated
G1 (first gap/gap 1) phase
• Growth and rapid biosynthesis
• Longest part of cell cycle CELL DIVISION
• Start of production of nucleotides Karyokinesis: nuclear division
• Arrested cellular activities during mitosis are
reactivated Mitosis
• Cell enlarges • Occurs in all multicellular plants and animals to permit
• Organelles multiply growth of the organism
• Mitochondrion DNA and plastids increase • 2N, diploid, somatic cells
• Not applicable for sex cells/gametes
S (synthesis) phase • Duplication division
• Growth and DNA replication/synthesis
1|P a g e
LIANRPh
