Simple Tissues
a tissue made of one type of cell
Complex tissues
tissues made from two or more types of cells
Meristematic tissues
permanent regions of growth where cells actively divide
Ground tissues and Function
Includes al tissues that are neither dermal nor vascular
Function: metabolism, storage, and support
3 Components of Ground Tissues
Parenchyma
Collenchyma
Sclerenchyma
2 Components of Dermal Tissues and Function
Epidermis and Periderm
Function: protection and prevent desication
2 Components of Vascular Tissue
Xylem and Phloem
Simple Tissues produced by Meristems
Parenchyma
Collenchyma
Sclerenchyma
aka ground tissues
Complex Tissues produced by Meristems
Xylem
Phloem
Epidermis
Peridermis
Secretory Cells and Tissues
Parenchyma
A ground tissue composted of parenchyma cells that tend of have large vacuoles.
Parenchyma cells
Cells commonly present in the primary cell wall with a greater ability to divide for regeneration and wound healing.
Function: photosynthesis, movement of water and transport of food in plants, storage and secretion.
This is the most common cell type
Aerenchyma
Refers to parenchyma tissues with extensive connected air spaces mostly found in aquatic and wetland plants
Parenchyma cells
cells with spaces between them found in parenchyma or aerenchyma tissue
Collenchyma Cells
Thicker Cells with a living cytoplasm that remain alive for a long time that occur beneath the epidermis and provide a flexible support for leaves and floral parts
Chlorenchyma vs. Collenchyma
Chlorenchyma have chloroplasts containing parenchyma cells, a soft uniform thin cell wall, and can store as well as photosynthetic.
Collenchyma may or may not have chloroplats, hard uneven thickened cell walls, and mechanical function as well as photosynthetic.
Chlorenchyma
Parenchyma cells containing many chloroplasts. Chlorenchyma tissues mainly function for photosynthesis.
If they don’t have chloroplasts, they exist for food and water storage
Sclerenchyma Tissue
Consists of cells with thick, tough secondary walls that are normally impregnated with lignin
They are dead at maturity and function as support
Two types of Sclerenchyma
Sclereids and Fibers
Sclereids
A reduced form of sclerenchyma with highly thickened lignified walls that cause the grittiness of pears and the hardness of nut shells and drupes
Fibers
A form of sclerenchyma found in association with different tissues in roots, stems, leaves, and fruits with an important economic value for manufacturing textile goods, ropes, string, canvas, and more
Xylem consists of…
Parenchyma cells
Fibers
Vessels
Tracheids
Ray cells
Xylem Vessels
Vessel elements have thick secondary cell walls and are open at the ends. They are stacked end-on-end to form long tubes
Tracheids
A part of the xylem that’s dead at maturity, and have a relatively thick secondary cell walls.
They have pits that allow water to pass from cell to cell
Ray Cells
Long lived parenchyma cells produced in horizontal rows that function as food storage and found in the xylem
