Life Processes In Plants 🪴 And Animals 🦍 Flashcards
- Functions of stem
Supports Ariel parts of plant.
- Functions of stem
Allows water to move from roots to leaves.
- Functions of stem
- Allows manufactured food from leaves to move to all parts of the plants.
Arrangement of Vascular Tissue in Dicot
Epidermis consists of :
- Outer ring
- Cuticle
- Woody stems
Outer ring
Covered by a transparent waxy cuticle.
Cuticle
Prevents water loss via transpiration.
Woody stems
Epidermis consists of many layers of cells that form the bark.
Hypodermis
Sclerenchyma or collenchyma present.
Provides support
Arrangement of Vascular tissue in dicot stem:
Epidermis
Hypodermis
Sclerenchyma cap
Vascular bundle
Xylem
Cambium
Phloem
Pith
Cortex
Sclerenchyma Cap
Provides support
Vascular bundle consists of:
Sclerenchyma
Phloem
Cambium
Xylem
Sclerenchyma cap in vascular bundle
Provides support
Phloem
Transports food
Cambium
Between phloem and xylem
Xylem
Transports water and mineral salts
Pith
- Thin walled parenchyma cells.
- Found towards centre of stem.
- Stores starch.
Cortex consists of
Thin walled parenchyma cells.
Dicotyledonous.
Scelerenchyma
Thin walled parenchyma cells
Provide support stem when they are turgid.
Dicotyledonous
Outer cortex form hypodermis which is made up of collenchyma and scelerenchyma cells.
Collenchyma
Walls thickened at corners
Sclerenchyma
Evenly thickened wall.
Secondary growth in dicotyledonous stems
Refers to increase in the thickness ( girth ) of a plant as it gets older.
- Secondary xylem and Secondary phloem.
Secondary thickening in a dicotyledonous stem results from the development of a Circular layer of cambium cells that forms between xylem and phloem.
- Secondary xylem and Secondary phloem.
Between vascular bundles in line with the vascular Cambium, found in parenchyma cells. Cells become meristematic and undergo repeated mitosis.
- Secondary xylem and Secondary phloem
Ring of cambium cells produce Secondary xylem.
Annual rings
Each year a new ring of secondary xylem forms which is referred to as annual ring.
Woody stems
Annual rings are visible when a tree trunk is cut .
- Annual rings
Each ring represents one year
Thick annual ring
Indicates the water was plentiful.
Thin annual ring
Indicates that the plant experienced a relatively dry year.
Cork formation
Cork cells develop towards the outer surface of a dicotyledonous stem.
Cork cells replace?
Replace cortex and epidermis with bark which protects vascutissue of stem.
Suberin
Oily substance that prevents water loss from stem.
Lenticels
Tiny openings in stems surface allow for exchange of gases between stem and atmosphere.
Plants absorb?
Plants absorb water and mineral salts from soil via roots.
Xylem tissue
Transports water and mineral salts through the roots , stems and leaves.
Manufactured food during photosynthesis
Transported to all parts of the plant via the phloem tissue.
Xylem tissue ..
- Xylem Vessels
- Xylem trachieds
- Function of xylem tissue
Transports absorbed water and mineral salts from roots to stems and leaves.
- Function if xylem tissue
Gives plants strength
Lignin
Strengthens xylem tissue
