Plant Growth and development Flashcards
What are plants composed of?
composed of cells, tissues and organs
tissue
is a group of cells, consisting of one or more cell types, that together perform a specialized function.
organ
consists of several types of tissues that together carry out particular functions
What are the 2 organ system?
Shoot system
Root system
Root system
below ground organs of the plant
All of a plant’s roots, which anchor it in the soil, absorb and transport minerals and water, and store food.
shoot system
(above ground organs of the plant)
The aerial portion of a plant body, consisting of stems, leaves, and (in angiosperms) flowers.
photosynthates
the sugars and other carbohydrates produced during photosynthesis, are imported from the shoot system.
What does the shoot system depend on? Root system?
are almost never photosynthetic; the sugars and other carbohydrates produced during photosynthesis, are imported from the shoot system
the shoot system depends on the water and minerals that roots absorb from the soil
What does the shoot system consist of?
stems
leaves
What do stems consist of?
Nodes
Internodes
Shoot apical meristem (SAM)/Apical buds
Axillary buds
What do leaves consist of?
Blades
Petioles
Veins -
Nodes
leaf attachment points
Internodes
stem between leaves
Shoot apical meristem (SAM)/Apical buds
grows up (aka terminal bud)
Axillary buds
can form lateral branches, thorns
Blades
flattened part of the leaf for photosynthesis
Petioles
joins the blade to the stem
Veins
vascular tissues
What does the root system consist of?
Taproots (eudicots)
Lateral roots
• Root hairs
Root apical meristem (RAM)
Taproots
(eudicots) -> main vertical root
energetically expensive to make, allows the plant to be taller, giving it access to more favourable light conditions and, in some cases, providing an advantage for pollen and seed dispersal
Lateral roots
sides roots
have root hairs
Root hairs
extensions of epidermal hairs for increased absorption
Root apical meristem (RAM)
increases root length
root
is an organ that anchors a vascular plant in the soil, absorbs minerals and water, and often stores carbohydrates and other reserves
primary root
originating in the embryo, is the first root (and the first organ) to emerge from a germinating seed
fibrous root system
a thick mat of slender roots spreading out below the soil surface
most monocots, the primary root dies early on and does not form a taproot.
prop roots
suport super tall trees
storage roots
store food and H20
pneumatophores
air roots on aquatic plants to obtain oxygen
green roots
photosynthetic roots in aerial plants
strangling aerial roots
anchor the plant in branches to the ground
Modified stems
horizontal stem- rhizomes
stolon- asexual runners
tubers- enlarged ends of rhizomes of stolons for food storage
modified leaves
spines- protection
storage leaves
reproduction leaves- cloning/ asexual reproduction
tendrils- climbing
stem
is an organ that raises and separates leaves, exposing them to sunlight
What are the types of tissue systems?
Dermal tissue system
Vascular tissue system
Ground tissue system (
Dermal tissue system
protective tissue layer
Epidermis
The dermal tissue system of nonwoody plants, usually consisting of a single layer of tightly packed cells.
Cuticle
waxy, protective layer on stems and leaves
Periderm
The protective coat that replaces the epidermis in woody plants during secondary growth, formed of the cork and cork cambium.
Guard cells
specialized epidermal cells for gas exchange
Trichomes
hairlike cells that reduce water loss, reflect excess light, defense
Vascular tissue system
transport tissue layer
What does the dermal system include?
Epidermis -> outermost cell layer
Cuticle -> waxy, protective layer on stems and leaves
Periderm->layer in woody plants that replaces the epidermis during secondary growth
Guard cells->gas exchange
Trichomes -> hairlike cells that reduce water loss, reflect excess light, defense
What are the different types of vascular system tissue?
Xylem -> water conducting tissue
Phloem -> transports photosynthates
Stele -> xylem + phloem
xylem
Vascular plant tissue consisting mainly of tubular dead cells that conduct most of the water and minerals upward from the roots to the rest of the plant.
phloem
Vascular plant tissue consisting of living cells arranged into elongated tubes that transport sugar and other organic nutrients throughout the plant.