Study Set Content:
The water conducting cells of flowering plants.
perforation plate
they are dead at maturity and have relatively thick secondary cell walls, tapered at each end, the ends overlapping with those of the other (answer). They have no openings like vessels but are usually pairs of pits.
Tracheids
The chief water-conducting cells in gymnosperms and seedless vascular plants such as ferns
Tracheids
Thickened region in bordered pits
Torus
also function in food storage are long-lived parenchyma cells that are produced in horizontal rows.
Ray cells
A complex vascular tissue that conducts foods (carbohydrates) throughout the plant botany.
Phloem
What is phloem mostly composed of
2 types of cells without secondary walls
: large, more or less cylindrical, narrower more tapered companion cells closely associated with them
Sieve tube members
sieve tube members are made up of
ray cells, parenchyma, fiber
End walls have no large openings; the walls are full of small pores through which cytoplasm extend from cell to cell.
Sieve tube
Porous region of the sieve tube members. It is located at the cell walls end.
Sieve plates
what doe sieve tube members lack at maturity
Nuclei
cytoplasm is very active at conduction of food materials in solution throughout the plant
Sieve tube members
polymer contained in sieve tube members that stay in the solution as long as the cell contents are under pressure.
Callose
plug that prevents leaking if the sieve tube contents.
Callus
found in ferns and cone-bearing trees are like sieve tube member but tends to overlap at their ends rather than form continuous tubes. No nuclei and no adjacent companion cells.
Sieve cells
equivalent to companion cells and apparently function in the same manner.
ADJACENT ALBUMINOUS CELLS:
assists in the functioning of teh sieve tube element. It is a living cell with nucleus.
Companion cells
Two way flow
Phloem
Thick walls stiffened with lignin
Xylem
