Plant Growth
Plant Growth
Trumpet vine
Patterns of Growth
1. Annual
Germinate, mature &
reproduce in one year
E.g. marigolds
petunias
Patterns of Growth
2. Biennial
Takes two years to germinate,
mature & reproduce
carrots
flax
Patterns of Growth
3. Perennial
– lives for
many
years
Maple tree
Chrysanthemum
Growth in Meristems
Meristems
The growing regions of
plants
Where cells continually
divide
Meristematic Tissue
Only type of plant tissue that
makes new cells by mitosis
Cells will change into the 3
types of plant cells shortly
after division
Location: roots & shoots
Meristem Locations
Types of Meristems
1. Apical
2. Intercalary
3. Lateral
4. Axillary
Apical Meristems
At tips of stems, branches,
& roots
Cause plant to grow taller,
roots to grow deeper
Intercalary Meristems
Location: above the bases
of leaves & stems
Allow grass leaves to
quickly re-grow after being
mowed or grazed
Lateral Meristems
Allow stems & roots to increase in
diameter (i.e. get thicker)
1. Vascular cambium – btwn. xylem &
phloem, makes vascular tissue
2. Cork cambium - outside phloem
- Produces cork (e.g. bark of trees)
(dead cells that replace epidermis in
woody stems & roots f(x) = protection)
-
Axillary Meristems
In the joints where leaves
attach to the stems
Coleus shoot tip
Leaf
Leaf primordia
Apical meristem
Axillary meristem
Types of Growth
1. Primary Growth
– elongation (stems & roots)
- in all plants
2. Secondary Growth
- makes the plant
thicker
- in all dicots,
but not in all monocots