3.2 PLANT MORPHOLOGY

Bryophytes

* non-vascular plants


* no fluid conducting tissues
* cannot afford to be big
* example: moss

Ferns

* seedless


* propagates via spores
* vascular
* non-flowering plants

Gymnosperms

\- naked seed plants

* not contained within flowering plants
* ex: pine trees, conifers

Angiosperms

\- true flowering plants

Cotyledon

* contains the seed embryo
* a type of thickened leaf that is part of the developing plant inside a seed
* either stores food or grows from the seed to produce food

single cotyledon

Monocots Seed

parallel veins

Monocots Leaves

multiples of three

Monocots Flowers

scattered vascular bundle

Monocots Stems

fibrous

Monocots Roots

corn/maize kernels

Monocots examples

two cotyledon

Eudicot Seed

branches veins

Eudicot Leaves

multiples of four or five

Eudicot Flowers

bundles arranged in a ring

Eudicot Stems

taproot

Eudicot Roots

sitaw

Eudicot Example

Flowers

* made up of specialized leaf like structures


* germinative cells

Root system

* anchors and provides nutrients for the shoot system


* responsible for uptake of vitamins and minerals

Radicle

first root that comes from a plant

1\. absorption of water and inorganic nutrients

2\. anchoring of the plants body to the ground and support

3\. storage of food and nutrients

4\. vegetative reproduction and competition with other plants

Function of roots

Prop roots

* provides extra support
* props the plants above the substrate
* for greater aeration especially during flooding
* for plants that are occasionally, we submerged in water

Storage roots

nutrients and carbohydrates are stored for the plant

Buttress roots

* provides support for trees that are heavy while gathering ingredients in the atmosphere
* found in shallowly rooted trees and in nutrient poor soils

Aerial roots

* function as anchors, affixes plant to a structure


* capable of absorbing moisture

Pneumatophore

* lateral roots
* extended from the plants in the
* distance - grows distances away and then upward
* function for oxygen intake
* found in mangroves, mudflats

Shoot system

* consists of stem and leaves


* where photosynthesis takes place

1) Support for and the elevation of leaves, flowers and fruits. The stems keep the leaves in the light and provide a place for the plant to keep its flowers and fruits.

2) Transport of fluids between the roots and the shoots in the xylem and phloem

3) Storage of nutrients

4) Production of new living tissue.

Functions of stems

Rhizome

* horizontal underground plant
* storage function: scratches, proteins
* for unfavorable conditions

Rhizome

Ginger

Tubers

* modified type of rhizome
* also has a storage function; a food reserve
* thicker and rounded
* capable of creating buds
* for replanting or duplication

Tuber

potato

Stolons

* grow along the ground
* grows roods at certain nodes

Stolons

strawberries

Bulb

stems with layers

Bulb

onion

Corm

does not have storage leaves

* solid texture vs. separate storages in bulbs

Corm

taro

Leaves

\- main photosynthetic organ

petiole

a stalk that connects the blade with the leaf base

Simple leaf

one whole leaf

Compound leaf

leaf that has leaflets

Doubly compound leaf

* leaflets have leaflets


* ex: malunggay

Spines

protective, defensive leaves

Storage leaves

example is succulents

Plantlets

* capable of being separated to grow into another plant


* for reproduction

Tendrils

for support

Bracts

attractants for pollinators

dermal

vascular

ground

Three types of tissue system

Dermal (protoderm)

outer covering

Vascular (procambium)

conducts water and solutes

xylem

transports water from roots to stems and leaves

tracheids, vessel members

composition of vascular tissues

tracheids

spindle shaped

vessels

cylindrical shape

phloem

* translocates sap (carbohydrates and other nutrients)


* the food conducting tissue

sieve cell

elongated, spindle shape that is phosphorus

sieve tube element

also has spores

* non-living, no nucleus
* similar function as tracheids

sieve plate

also is phosphorus

companion cell

* small parenchyma cells beside the sieve tube elements


* has nucleus
* maintains sieve tube elements

Ground (ground meristem)

carries out photosynthesis, photosynthetic product, and helps support the plant

Parenchyma

ground meristem that have **thin** walls

Parenchyma

ground meristem that have large central vacuoles

Collenchyma

ground meristem primarily for supporting cells with primary walls

Collenchyma

ground meristem with corners that are thick

Collenchyma

ground meristem able to **store nutrients**: starch, lipids

chlorenchyma

ground meristem capable of photosynthesis

Sclerenchyma

ground meristem that has thickened secondary cell wall

Sclerenchyma

ground meristem that provide **rigid support**

Sclerenchyma

many are functional when dead

fibrous

* type of sclerenchyma
* elongated fibers
* cross-section
* usually in woody plant parts/bark of trees"

sclereids

* type of sclerenchyma
* have various shapes and may pack together densely


* nut shell or seed coats
* stone cells : found in pears
\*rough texture"

Plant Cells

\- contain chloroplasts or other plastics and vacuoles, and possess cellulose-containing cell walls

* cell walls often corresponds to the special functions of the cell.

Dermal layer

Found in the upper and bottom part of the cross-section

Stoma

pores for water transpiration

Guard cells

cells that surround the stomata

Sclerenchyma

* found under the dermal layer


* part of the mesophyll portion

Mesophyll

sandwiched bet. upper and lower epidermis

Palisade

* found just below the cuticle/upper epidermis


* more concentrated

Spongy

* found above the **lower epidermis**
* less concentrated

Vein

represents the vascular tissues (xylem, phloem)

Apical

refers to the apex

Apical meristem

* responsible for primary growth
* increase in height or length

Meristematic

* Highly mitotic


* **active cell division**

Lateral meristem

* responsible for secondary growth


* expansion of plant body (width, girth, or diameter)

Shoot apical meristem

* upward growth


* darkly colored because it is very dense and concentrated

Leaf primordia

* young leaves associated with the apex part


* provides some protection for the shoot apical meristem

Root apical meristem

downward growth

**Root cap**

* a covering


* some daughter cells become part of the root cap


* constantly being eroded

Division

zone where there is increase in the number of cells

Elongation

zone where there are cells that are becoming longer

Maturation

zone where there presence of root hairs

Quiescent center

* portion wherein **cell division is not really active**


* fully surrounded by other cells of the zone

Monocot root

circumferential vascular bundle

pith

surrounded by a ring of xylem and phloem

Dicot root

scattered vascular bundle

Pericycle

* layer surrounding the vascular tissue of the root


* where the lateral root emerges

Vascular tissue

* xylem is internal to the phloem


* organized

Vascular cambium

situated in between xylem and phloem

Lateral root

* deeper base


* will develop its own vascular tissues
* originates from the pericycle