Stems I Primary Structure of Stems Dermal Epidermis
- Slides: 28
Stems - I
Primary Structure of Stems • Dermal – Epidermis • Ground Tissue – Cortex – Pith – Other • Vascular Tissue – vascular bundles – Collateral VB – Bicollateral VB – Concentric VB
Acorus stem with endodermis
Amphivasal VB
Morphological concepts used to explain primary anatomy • Stelar Theory • Leaf Trace Theory
Types of steles Protosteles -------> Siphonosteles------->
Protosteles have a central core of vascular tissue surrounded by cortex (not shown) Xylem Phloem
Haplostele in Psilotum rhizome
Haplostele in Selaginella root
Actinostele in Psilotum stem
Actinostele in Ranunculus root
Plectosteles in Lycopodium stems
Siphonosteles have a central pith surrounded by a cylinder of vascular tissue Ectophloic Siphonostele Amphiphloic siphonostele Dictyostele
Ectophloic siphonstele in fern rhizome with a ring of xylem surrounded by a ring of phloem
Amphiphloic siphonostele in a fern rhizome with two rings of phloem on each side of xylem
Leaf traces and leaf gaps
Siphonostele with a leaf gap and leaf trace
Dictyosteles are considered amphiphloic siphonosteles with overlapping leaf gaps
Modified siphonosteles
Eustele Dicots and gymnosperms Monocots
Evolution of stelar types
Flattened protostele in Selaginella stem Flattened haplostele? OR Actinostele with two arms?
Actinostele with irregular shape Or a plectostele with connections between xylem areas?
Stele in stem Asteroxylon (fossil member of Division Lycophyta)
Leaf traces originate at the apical meristem
Leaf traces
Anatomy of nodes Unilacunar with 2 traces Trilacunar with 3 traces Unilacunar with 1 trace Multilacunar with many gaps and many traces
- Dermis microscope
- Uneven junction of the dermis with the epidermis
- Functions of stem
- Tissue meaning in biology
- Example of dermal tissue
- Dermal papillae
- What is dermal nitrate test
- Lateral growth in plants
- Puncture equipment
- Tejidos vasculares de la planta
- Sea urchin diagram
- Dermal ossicles
- Echinoderms characteristics
- Fistulectomy
- Dermal zones of jaundice
- Factors affecting dermal penetration of drugs
- Dermal or epidermal tissue system
- Glassy membrane hair
- Functions of stems
- Fascia
- Hair root plexus
- Derinin ekleri
- Likotis
- Upper vs lower epidermis
- Epidermis layers
- Penampang tumbuhan
- Tricladida
- The integumentary system facts
- Hipodermis funcion