Plant Form Flashcards
A vascular plant consists of what 2 things?
root system and shoot system
What does a root system function in?
anchors plant, used to absorb water and ions
What does a shoot system function in?
consists in supporting stems, photosynthetic leaves, and reproductive flowers; iterative unit consists of internode, node, leaf, and axillary bud
What are meristems?
regions of plant that reman embryonic, divide throughout life of plant resulting in indeterminate growth
What activities do meristems participate in?
clumps of sm. cells with dense cytoplasm and large nuclei, act as stem cells do in animals (one cell divides and form 2 cells, one remains meristemic and other contributes to plant body), one cell divides producing a differentiating cell and another remains meristemic, extension of shoot and root produced by apical meristems
What do lateral meristems produce?
increase in shoot and root diameter
What is the location and function of the apical meristem?
Location: tips of stems and roots
Function: growth, increase length at tips
What is the location and function of the intercalary meristem?
Location: between tip and base of stems and leaves
Function: growth, increase length between nodes
What is the location and function of the lateral meristem?
Location: sides of stems and roots
Function: growth, increase diameter
What does the apical meristem give rise to?
primary tissues aka primary plant body
What does the root cap protect?
root apical meristem
What does the leaf primordial protect?
shoot apical meristem
What are intercalary meristems?
arise in stem internode, add to internode length
Where are lateral meristems found?
found in plants that exhibit secondary growth
What are secondary tissues called?
secondary plant body
Woody plants have 2 types of lateral meristems? What are they?
cork cambium and vascular cambium
What does cork cambium produce?
outer bark
What does vascular cambium produce?
secondary vascular tissue, secondary xylem is the main component of wood
Roots and shoots are composed of what 3 basic tissues?
dermal, ground, and vascular
What is the dermal tissue?
outer protective cover, once cell layer thick
What is the ground tissue?
function in storage, photosynthesis, and secretion
What is the vascular tissue?
conducts fluids and dissolved substances
How does the cell wall grow?
from inside to out
What special cells does the dermal tissue have?
guard cells, trichomes, and root hairs
What are guard cells?
paired sausage-shaped cells, flank a stoma-epidermal opening
What are trichomes?
cellular or multicelluar hairlike outgrowths of the epidermis; keep leaf surfaces cool and reduce evaporation by covering stomatal openings; some are glandular, secreting substances that deter herbivory
What are root hairs?
tubular extensions of individual epidermal cells, greatly increase root’s surface area and efficiency of absorption
What are the 3 cell types of ground tissue?
parenchyma, collenchyma, and sclerenchyma
What does parenchyma help with?
function in storage, photosynthesis, and secretion
What does collenchyma help with?
provides support and protection
What does sclerenchyma help with?
provides support and protection
What are some characteristics of parenchyma cells?
most common type of plant cell, living protoplasts, less specialized than other plant cells
What are some characteristics of collenchyma cells?
provide support for plant organs, allow bending without breaking, living protoplasts
What are some characteristics of sclerenchyma cells?
tough thick walls, usually lack protoplasts at maturity, secondary cell walls often contain lignin, 2 general types which both strengthen tissues (fibers and sclerids)
What is xylem?
principal water-conducting tissue, vessels, tracheids, vessel members tend to be shorter and wider than tracheids
What are tracheids?
dead cells that taper at the end and overlap one another