Plants Flashcards
Two types of seed plants
Gymnosperms(conifers) and the Angiosperms(flow ring plants)
Angiosperms are divided into 2 groups:
Dicots and monocots
Dicots:
2 cotyledons,
In 4s,5s,
Netted and organized in a circle
Monocots
1 cotyledon,
Parallel,
3s
3 Types of Plant Tissue
Ground tissues
Dermal tissues
Vascular tissues
Ground tissues: Collenchyma
Cells which have thick but flexible cell walls, serve mechanical support functions.
Ground tissue: Parenchyma
Most common, has thin walls, storage, photosynthesis, and secretion.
Ground tissues: Sclerenchyma
Thicker walls than collencyma, also provide mechanical support functions.
Dermal tissue
*Cuticle
Covers and protects the plant. It includes the EPIDERMIS and modified cells like guard cells, root hairs, and cells that produce a waxy cuticle.
Vascular tissue: consists of 2 major kinds of tissues
*vascular bundles
Xylem and phloem. The two usually occur together to form VASCULAR BUNDLES.
Two types of Xylem cells
Tracheids and Vessel elements.
Xylem functions
- 2 types of cells:
- Pits
The conduction of water and minerals. They travel up.
Have 2 types of cells:tracheids and vessel elements
Sometimes Xylem cells has PITS, or places where the secondary cell wall is absent.
Xylem: tracheids
Tracheids, are long and tampered, water passes from one tracheid to another through pits on the overlapping tapered ends of cells.
Vessel members(vessel elements)
Are generally wider, shorter, thinner, walled, and less tapered than tracheids.
Most angiosperms have both tracheids and vessel members.
Xylem: Proferations
Literally holes between cells. Because of this, water movement through vessel members are more efficient than through tracheids.
Phloem
Transports sugars.
Phloem: companion cells
Companion cells are living parenchyma cells that lie adjacent to each sieve-tube member.
Phloem: plasmodesmata
Maintain physiological support to the nuclei-lacking sieve-tube members.
Phloem: Sieve-tube members(elements)
Living at maturity and lack nuclei/ribosomes.
The seed consists of…
An embryo, a seed coat, and some kind of storage material.
The seed: major storage material may be an:
Endosperm or cotyledons.
The seed:dormant
After a seed reaches maturity, it remains dormant until specific environmental cues(like water or temperature) are encountered.
The seed: Cotyledon
Seed leaf within the embryo of a seed.
The seed: the embryo consists of 5 parts
- epicotyl
- Pumule
- Hypocotyl
- Radicle
- Coleoptile
- epicotyl- top portion of the embryo
- Pumule- attached to the epicotyl(young leaf)
- Hypocotyl- below the epicotyl
- Radicle- develops below the hypocotyl. Develops into the root.
- Coleoptile(in monocot)-surrounds and protects the epicotyl
The seed: apical meristems
*Where are they found?
Responsible for vertical growth and found at root and shoot (apex) tips.
The seed: zone of maturation
Where cells mature into xylem,phloem, parenchyma, or epidermal cells.
The seed: root tip(root cap)
Protects the apical meristem behind it.
The seed: Zone of Elongation
Newly formed cells absorb water and elongate.
The Leaf: Guard Cells
What is the function?
Control the opening and closing of the STROMATA. Stromata are openings in the epidermis that allow gas exchange between the inside of the least and the external environment.
The Leaf: Guard Cells
-stromata
Control the opening and closing of the STROMATA. Stromata are openings in the epidermis that allow gas exchange between the inside of the least and the external environment.