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 flax carrots

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 Apical Intercalary Lateral 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) Vascular cambium – btwn. xylem & phloem, makes vascular tissue 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 primordia Leaf Apical meristem Axillary meristem

Types of Growth Primary Growth – elongation (stems & roots) - in all plants Secondary Growth - makes the plant thicker - in all dicots, but not in all monocots