Exam 1 Flashcards
Vascular tissue system
Function: conduction of water, nutrients, sugars, and hormones throughout the plant.
Tissues: xylem- conducts water and nutrients up roots, stems and leaves.
Phloem- conducts water, sugars, hormones, etc. down and up roots, stems and leaves; moves from where produced (called sources) to where needed (called sinks).
Dermal tissue system
Function: protection from the environment
Tissues: epidermis- single layer of cells on primary (herbaceous) plant parts.
Periderm or bark - corky tissue that replaces epidermis on secondary (woody) plant parts
Ground or fundamental tissue system
Function: storage. Support. Filler tissue and site of photosynthesis
Tissues: cortex- outer region of stems and roots
Pith- center of stems
Mesophyll- middle of leaves and flower pedals
What are the three basic cell types that compromise most of the tissue of plants?
Parenchyma
Collenchyma
Sclerenchyma
What is the parenchyma?
- thin non-lignified primary cell walls
- filler. Storage, protection, photosynthesis
- ex: flesh of potato, lettuce leaf.
- isodiametric
What is the collenchyma?
- unevenly thickened, non-lignified primary cell walls
- support in growing tissues
- ex: strings in celery stalks
- longer than wide
What are the two types of sclerenchyma?
Fiber(bamboo cane): Long slender and pointed on ends
Sclereid(seed coat) or stone wall(pear fruit): multi shaped or columnar.
What is sclerenchyma?
Evenly thickened , lignified (tough), secondary cell walls. Dead at maturity.
What is the cell wall?
Primary: herbaceous tissue,
Secondary: lignified tissue
What is a polysaccharide?
A polymer or chain of sugars
What are the three polysaccharides?
Cellulose: forms a matrix of microfibrils( chains of beta-1, 4-linked glucose)
Hemicellulose: filler between cellulose microfibrils (chain of misc. sugars)
Pectin: cementing agent or filler; high middle lamella and fruit;(chains of gala turnip acid)
What is lignin?
Tough polymer of phenolic compounds; high in secondary cell wall
What is protein?
Mainly structural (most commonly hydroxyproline) A polymer or chain of amino acids
What are the components of a cell wall?
Polysaccharide
Lignin
Protein
What is plasmalemma or plasma membrane?
The membrane that surrounds the cytoplasm; composed of a bilayer of phospholipids and proteins; its selectively permeable and regulates absorption into cells and leakage from cells.
What is plasmodesmata?
Tubular plasma membrane extensions through cell walls; connect adjacent cells
What is cytoplasm?
Cytosol plus organelles; most metabolism occurs in the cytosol or the organelles
What are the two components of cytoplasm?
Cytosol
Organelles
What is cytosol ?
Fluid portion of the cytoplasm ; a solution of dissolved/suspended compounds
What are organelles?
Specialized structures in cytoplasm, each with specific functions