Week 2: Plant morphology Flashcards
3 types of roots
Taproot
fibrous roots
adventitious roots
taproot
large primary root that extends straight down and tapers gradually
Fibrous root
many roots extends down from the stem
adventitious roots
arise rom non root tissue ( usu from stem)
Stems
Framework of a plant that supports leaves, flowers, and other structures.
A conduit for exchange of water, nutrients, sap
Can act as a place for storage of fuel
Can be an area of photosynthesis in green stems.
internal features of plants
epidermis
cortex
vascular tissue
pith
epidermis
outer layer of wax rated cells
cortex
tissue between the epidermis and the phloem
vascular tissue of plants
-carry water, nutrients, and photosynthates through the plant
Xylem
Cambium
Phloem
Xylem
caries water and minerals from the roots upward through the plant
Cambium
a single-cell layer of dividing tissue that creates the xylem on one side and the phloem on the other
Phloem
carries sugar down through the plant
Pith
the center of the stem that can be woody and dense chambered or hollow
Dicotyledon stems
see slide images
external features of plants
terminal bub lateral bud bud scales naked bud leaf scar bundle scar terminal bud
Terminal bud
but at the tip of the stem
lateral bud
grow from leaf axis on the side of a stem
bud scales
modified leaves that protect the bud
naked bud
a bud w.o scales
leaf scar
mark left where least was attached
bundle scar
the mark left where the vascular bundles passed though
terminal bud scale scare
The area where the previous year’s terminal bud scales were attached. This shows the growth pattern from year to year.
Bulb
underground storage leaves attached at a base
corm
short, thickened underground stem with scales that form a tunic. Corms are solid rather than having rings like an onion or cloves like garlic.
crown
a compressed stem with leaves above and roots below
stolon
– horizontal, above-ground runner that sets down roots or generates a plantlet at its nodes.
Rhizome
– horizontally growing underground stems
not actually a root
twining stem
used for climbing, some twist clockwise, some counter clockwise
tuber
an enlarged rhizome containing stored food. These structures have “eyes,” or modified buds dotted around them.
tuberous stem
– a storage stem with buds only on the “up” side.
external features of leaves
blade
petiole
margin
stipule
blade
the flattened part of the leaf
petiole
stalk of the leaf
margin
may be lobed toothed smooth etc
stipule
leaf-life appendages at the base of the leaf
what are the possible arrangements of stems
opposite
alternate
whorl
rosette
opposite leaves
on opposite sides the stem at the same level
Alternate leaves
leaved at alternating levels on the stem ( staggered)
whorl leaves
3 or more leaves at the same level of the stem
Rosette leaves
a spiral pattern of attachments around the stem
leaf arrangement on petiole
- simple
- palmately compound
- pinnately compound
- double pinnately compound
Simple leaf
blade is on continuous unit
palmately compound
multiple leaflets radiation from a central point
pinnately compound
leaflets arranged on both sides of a common rachis ( stalk)
couple pinnately compound
common sub stalks and stalks
Flower parts
pistil stamen petal sepals receptacle pedicel
Pistil
female organ
Stigma – often sticky projection that receives pollen
Style – tissue between the stigma and the ovary
Ovary – contains ovules (unfertilized, immature seeds) and embryo sacs
stamen
male organ
Anther – pollen-producing organs
Filament – stalk supporting the anthers
Petals
collectively form the corolla
sepals
protective, leaf like covering for the flower bud collectively form the calyx
receptacle
base of the flower
pedicel
the stalk of an individual flower in an inflorescence
Inflorescence
arrangment of lowers on a stem
what are some inflorescence
solitary raceme spike umbels corymb
Cyme
a determinate inflorescence, inner flowers opening first
