35: Vascular Plant Growth & Development Flashcards
(33 cards)
Three tissue systems?
Dermal, vascular, ground tissue
What is the outer layer of plants and the waxy coating is called?
Epidermis; cuticle
What is the stele?
The stele is the tissue of the vascular system; in roots, it consists of a cylinder while in shoots it consists of bundles
What is the pith and cortex?
The pith is internal to the vascular tissue; the cortex is external to the vascular tissue.
Which plant cells lack secondary walls and retain the ability to differentiate?
Parenchyma cells; photosynthesis occurs here, some have amyloplasts
Which plant cell has a secondary wall, an uneven primary wall, is elongated at maturity, and functions in support?
Collenchyma cells; often found just below the epidermis of younger stems and petioles
Which plant cell is dead at functional maturity, is lignified, and has a thick secondary wall?
Scherenchyma cells
What are sclereids and fibers?
Sclereids and fibers are specialized entirely for support and strengthening. Sclereids are irregular in shape and have thick, lignified cell walls. Fibers are scherenchyma cells grouped in strands, and are long, tapered, and slender.
Tracheids and vessel elements function?
Tracheids and vessel elements are water-conducting cells of the xylem; tubular, elongated cells, dead and lignified at maturity
Tracheid vs vessel element? (found where, shape, etc)
Tracheids are found in all vascular plants; vessel elements are found in most angiosperms and some gymnosperms. Tracheids are long, thin cells with tapered ends; vessel elements are shorter, wider, and thinner. They are both hardened with lignin
What is a sieve-tube element? What is the function of the companion cell?
Sieve tube elements lack a nucleus, ribosomes, a vacuole, and cytoskeletal elements; the end walls between the elements, sieve tube plates, have pores that facilitate the transport of fluid from cell to cell
A companion cell is connected to the sieve-tube element via plasmodesmata
Where are apical meristems found?
Apical meristems are found at root and shoot tips, and enable primary growth, growth in length
Two types of lateral meristems? Function?
It enables secondary growth; the vascular cambium adds secondary xylem and phloem; the cork cambium replaces the epidermis with thicker periderm
Three types of tissues primary growth gives rise to?
Protoderm, ground meristem, procambium
Primary growth of roots? Three zones? Root cap?
Zone of cell division: includes stem cells of the root apical meristems
Zone of elongation: most growth occurs; root cells elongate
Zone of differentiation: the tissues of the root cells begin to differentiate into the protoderm, ground meristem, and the procambium
The protoderm gives rise to the
epidermis
What does the ground meristem consist of ?
It consists of mostly parenchyma cells in the cortex; the cortex stores sugars and transports water/salts
The endodermis is
The endodermis a single layer of cells found at the innermost layer of the cortex adjacent to the vascular cylinder
In roots, the procambium gives rise to
vascular cylinder
the pericycle
is a layer of cells in the roots that surrounds the vascular cylinder
In eudicots, the cross-section of the stele of the root looks like a ______; in monocots, the cross-section appears as a ______.
star; ring
apical dominance is
the closer an axillary bud is to an active apical bud, the more inhibited it is
In eudicots, the cross-section of the stele of the shoot looks like a ______; in monocots, the cross-section appears as a ______.
ring; scattered
What is leaf primordia?
Leaves develop from leaf primordia, projections shaped like cow’s horns that emerge along the sides of the shoot apical meristem
