Stems Flashcards
Give the 3 functions and uses of stem
- framework for leaves, flowers and seeds
- carry water and minerals from the soil throughout the plant
- source of wood, food and medicinal compounds
Swollen part where leaves, branches and buds are attached
Nodes
Distance between two successive nodes
Internode
Small, raised dots or ridges for gaseous exchange
Lenticels
Angle between the leaf and stem
Axil
Underdeveloped shoot
Bud
Marks below the axillary bud after a leaf has fallen
Leaf scar or scar
Cut ends of vascular bundle seen within each leaf scar
Bundle scar
What are the parts of the internal structure of a young dicot stem? (arrange)
Epidermis - Cortex (parenchyma and collenchyma cells) - Pith (middle) - vascular bundle (xylem and phloem) - Interfascicular cambium
What type of arrangement is present in a dicot stem?
Circular arrrangement
True or False: A dicot stem is an open type.
True
What type of arrangement is present in a monocot stem?
Scattered arrangement
True or False: A monocot stem is a closed type.
True
What are the three categories under apical meristem?
- Protoderm
- Ground meristem
- Procambium
What is the primary tissue under protoderm?
Epidermis
What is the primary tissue under ground meristem?
Ground tissues: pith and cortex
What is the primary tissue under procambium?
Primary xylem and primary phloem
True or false: The ground tissue will eventually become the cork cambium.
True
What are the two categories under cork cambium?
Cork and phelloderm
Produces the radial transport system and gives rise to parenchyma
Ray initials
Produces the axial transport system and gives rise to sieve-tube, companion cells, tracheids, vessel elements,, and fibers
Fusiform initials
True or false: Early wood = Summer wood
False, spring wood
True or false: Late wood = Spring wood
False, summer wood
Which of the two types of wood produce band rapidly and thicker?
Spring wood
Which of the two types of wood has darker growth rings and narrow layer of wood?
Summer wood
True or false: In tropical climates, growth rings are more even and hard to distinguish.
True
The science of age of trees
Dendrochronology
Inner circle in the wood
Heartwood
Outer circle in the wood
Sapwood
Give reasons as to why the heartwood darkens
- Breakage of water columns
- Fungal attack
- Formation of tylosis
- Metabolic changes
It is the upper-side of the stem which produces special gelatinous fibers whose walls are rich in cellulose
Angiosperms: Tension wood
It is the under-side of the branch which produces fibers whose walls are rich in lignin
Gymnosperms: Compression wood
The inner bark is also known as the ___?
Secondary phloem
The outer bark is also known as the ___?
Periderm layer
True or false: Pine stems have resin ducts
True
Yes or no: Formation of cambia around the vessels is an example of anomalous form of growth.
Yes
Yes or no: Formation of fibers in monocots is an example of anomalous form of growth.
Yes
Yes or no: When a type of secondary phloem is located between two bands of xylem, it is a type of anomalous form of growth.
Yes
Specialized stem: Green photosynthetic stems for reproduction and storage
Cladodes
Specialized stem: For storage and reproduction (ex. ginger, turmeric and wasabi)
Rhizome
Specialized stem: Short stem covered with fleshy blades (storage and reproduction)
Bulb
Specialized stem: For storage and reproduction (ex. gabi or taro)
Corm
Specialized stem: Swollen outgrowths of stolon for storage and reproduction (ex. potato)
Tubers
Specialized stem: Horizontal above the ground stem for reproduction (ex. strawberry)
Stolons or runners
Specialized stem: Mainly used for protection itself
Hooks, spines, and thorns
Specialized stem: Climbing . twining stem support
Twiner
Distributes sugar and minerals
Phloem
Conducts water and minerals
Xylem