Plant anatomy

Chapter 30

what does a vascular plant consist of

-a root system

—anchors the plants, absorbs water and minerals

-a shoot system

—supporting stems, photosynthetic leaves, reproductive structures

what are meristems?

-plant version of stem cells in animals

-clumps of small cells with dense cytoplasm and large nuclei

when meristem cells divide what does it produce?

-a permanent cell that can no longer divide

-a meristematic cell that can continue the process

what are apical meristems

-located at the tips of stems and roots

-give rise to three types of primary tissues and all resultant tissue types

-elongate the plant

-cause primary growth and branching

what are lateral meristems?

-increase thickness of plant

-add new vascular tissue (no ground tissue)

-cause secondary growth

—vascular and cork cambium

-only some angiosperms (dicots)

what are the three types of tissue systems in roots shoots and leaves

-dermal tissue

-ground tissue

-vascular tissue

what is dermal tissue

-for protection

-skin and bark

what is ground tissue

-for storage, photosynthesis and secretion

-provide little to no structural support

what is vascular tissue

-for conduction

-xylem: water and dissolved minerals

-phloem: nutrient containing solution

-MAY occur in vascular bundles

what are the four parts of a stem

-node

-internode

-axillary bud

-apical bud

what is a node

A point on a stem where leaves or branches originate; it is critical for plant growth and development.

what is an internode

The section of the stem between two consecutive nodes, where no leaves or buds arise.

what is the axillary bud

develops into branches with leaves or may form flowers

what is the apical bud

-extends the shoot system during the growing season

what cells are in ground tissue in the stems

-collenchyma cells

-sclerenchyma cells

what two types of sclerenchyma cells are there

-fibers

-sclereids

what are collenchyma cells

-provide flexible support for plant organs in stems

-uneven cell walls

what are sclerenchyma cells and what are the characteristics of the two general types

-sclerenchyma cells are usually dead at maturity, with thick secondary cell walls

—fibers: long, slender strands

—sclereids: variable shape, branchef

what are the three types of the dermal tissues found in stems

-epidermis

-stomata

-trichomes

what is the epidermis

-one layer in herbaceous plants

-bark in woody plants

what is the stomata

-(stoma=mouth)

-regulate CO2 and O2 uptake

-regulate water vapor loss

what is the trichome

-hairlike structures

-reduce water loss

-increase solar reflectance

-defend against predation

what are the two type of vascular tissues found in stems?

-xylem

-phloem

what is xylem

-water and mineral conducting tissue

-dead cells at maturity

what is the tracheid

-cells that taper and overlap

-found in xylem

what are vessels

-found in xylem

-continuous tubes of short/wide cylindrical cells

what is phloem

-main nutrient conducting tissue

what are sieve tube members

-found in phloem

-where stuff usually flows

what are companion cells

-found in phloem

-doing the living for sieve tube members

is the epidermis on the outside or the inside of stems

-outside

does ground tissue occurs throughout the stem?

-yes

what is pith

-inner tissue

what is the cortex

-outer tissue

what are vascular bundles

-usually have phloem on the outside and xylem more central

do woody plants have secondary growth?

-yes

do herbaceous plants have secondary growth

-yes, but very little

what are the two major lateral merisems?

-vascular cambium, cork cambium

what is the vascular cambium

-forms the secondary xylem and the phloem (leads to woody tissue)

-A XYLEM LAYER FORMS EACH YEAR AND RESULTS IN AN ANNUAL RING

what is cork cambium

-produces the periderm (type of epidermis) of bark and other tissues to protect stem/trunk

-produces lenticels (little holes in the bark) to allow in O2

what way does the rhizome grow underground

-horizontally

what are corms

-similar to rhizomes, except they are rounded and fleshy

what are tubers

-modified stems that may store starch

what do bulbs function as

-a underground storage unit

what do runners and stolons do

-they run almost parallel to the ground/ just below the surface and give rise to new plants

what are tendrils

-slender, twining strands that enable a plant to seek support by climbing on other surfaces

what are thorns

-modified branches appearing as sharp outgrowths that protect the plant

what are the two types of roots

-tap root system

-fibrous root system

what is the tap root system

-main root that grows down vertically and from which many smaller lateral roots arise

-primarily dicots

-can develop additional root fibers

what is the fibrous root system

-located closer to the soil surface, and forms a dense network of roots

-primarily gymnosperms and monocots

-also adventitious roots (arising from above ground stem)

what are the three types of root growth

-area of cell division

-area of elongation

-area of maturation

what is the area of cell division

-covered by root cap to protect dividing meristem cells

what is the area of elongation

-cells take in water and grow

what is the area of maturation

-cells mature into permanent cells (have all their tissues)

what are the three types of tissues in roots

-ground tissue

-vascular tissue

-dermal tissue

how is ground tissue arranged in roots

-arranged in cortex (outer) and pith (pith tends to be reduced)

how is vascular tissue arranged in monocot roots

-arranged in rings of xylem and phloem

how is vascular tissue arranged in dicot roots

-xylem in star shape

-phloem surrounds

how is dermal tissue arranged in roots

-epidermis has root hairs (like trichomes but below ground)

-higher SA more H2O

what is endodermis

-outside of vascular bundles

-waterproof waxy layer = casparian strip

what are the three parts of leaves

-lamina

-petiole

-venation

what is the lamina

-flattened blade of leaf

what is the petiole

-stalk of leaf

what is the venation

-pattern of vascular bundles in a leaf

what has parallel leaves

-monocots

what has reticulated leaves

-dicots

what has dichotomous leaves

-gymnosperms

what is a phyllotaxy

-arrangement of leaves on a stem

what are the three types of leaf arrangement

-alternate (most common)

-opposite

-whorled

what is a simple leaf

-undivided blade

-blade has other shapes

-lobes like an oak tree could be an example of a simple leaf

what are compound leaves

-completely divided blade

-forms leaflets

what are the two types of compound leaves

-palmety

-pinnately

what are palmately leaves

-(like palm of hand)

-leaflets that radiate outwards from one point

what are pinnately leaves

-(feather like)

-leaflets are arranged around the midrib

what are the three things epidermis can have

-cuticle

-stomata

-trichomes

the mesophyl is what kind of tissue between the upper and lowder epidermis?

-parenchyma

-(ground tissue in leaves)

how many types of mesophyll do monocot leaves have

-one type

how many types of mesophyll do dicots have

-two

what is the two types of mesophyll dicots have called

-palisade mesophyll

-spongy mesophyll

what is palisade mesophyll

-two rows of tightly packed cells

-closer to the top

what is spongy mesophyll

-loosely arranged cells with air spaces

-closer to the bottom