plant cells
CHAPTER 36
PLANT CELLS
The first barrier to form between daughter cells is the middle lamella.
Daughter cells expand to their final size and make polysaccharides for a primary wall.
After expansion stops waterproofing materials are added for a secondary wall.
Water and dissolved materials move from cell to cell by way of pit pairs. A pit is a thin spot in the primary wall where the secondary wall is absent or separated from the primary wall by a space.
Strands of cytoplasm called plasmodesmata pass through pit pairs and the middle lamella to allow substances to move from cell to cell
Parenchyma cells- they store substances in their cytoplasm. Starch is stored in leucoplasts, lipids in oil droplets, and photopigments in chloroplasts.
Sclerenchyma cells- they are for support. There are two types of sclerenchyma cells:
1. Fibers- they are in bundles and give rigid support to wood and bark
2. Sclereids- they form shells for nuts and coats for seeds by being packed tighly.
Collenchyma cells- they lack a secondary wall and give support to petioles, nonwoody shoots and growing organs of the plant.
Tracheary elements- cells found in the xylem of tracheophytes that die before they transport water and dissolved minerals.
Tracheids- the tracheary elements of gymnosperms.
Vessel elements- the tracheary elements of angiosperms.
Sieve tube member- living cells of the phloem in flowering plants that transport foods from their sources to the tissues.
PLANT TISSUES
Tissue- an organized group of cells working together as a functional unit
Simple tissue- tissue made of one type of cell (parenchyma cells, parenchyma tissue)
Complex tissue- tissue made of more than one type of cell (parenchyma cells and sclerenchyma cells in the same tissue)
Plant tissues are organized into three tissue systems that extend throughout the plant:
1. vascular tissue system- conducts materials from one part of the body to another
2. dermal tissue
PLANT CELLS
The first barrier to form between daughter cells is the middle lamella.
Daughter cells expand to their final size and make polysaccharides for a primary wall.
After expansion stops waterproofing materials are added for a secondary wall.
Water and dissolved materials move from cell to cell by way of pit pairs. A pit is a thin spot in the primary wall where the secondary wall is absent or separated from the primary wall by a space.
Strands of cytoplasm called plasmodesmata pass through pit pairs and the middle lamella to allow substances to move from cell to cell
Parenchyma cells- they store substances in their cytoplasm. Starch is stored in leucoplasts, lipids in oil droplets, and photopigments in chloroplasts.
Sclerenchyma cells- they are for support. There are two types of sclerenchyma cells:
1. Fibers- they are in bundles and give rigid support to wood and bark
2. Sclereids- they form shells for nuts and coats for seeds by being packed tighly.
Collenchyma cells- they lack a secondary wall and give support to petioles, nonwoody shoots and growing organs of the plant.
Tracheary elements- cells found in the xylem of tracheophytes that die before they transport water and dissolved minerals.
Tracheids- the tracheary elements of gymnosperms.
Vessel elements- the tracheary elements of angiosperms.
Sieve tube member- living cells of the phloem in flowering plants that transport foods from their sources to the tissues.
PLANT TISSUES
Tissue- an organized group of cells working together as a functional unit
Simple tissue- tissue made of one type of cell (parenchyma cells, parenchyma tissue)
Complex tissue- tissue made of more than one type of cell (parenchyma cells and sclerenchyma cells in the same tissue)
Plant tissues are organized into three tissue systems that extend throughout the plant:
1. vascular tissue system- conducts materials from one part of the body to another
2. dermal tissue