79 terms

AP Biology Chapter 35: Plant Structure, Growth, Development

an organism's ability to alter itself in response to local environmental conditions
external form
a group of cells with a common function, structure, or both
several types of tissues that together carry out particular functions
root system
a system of roots
shoot system
consists of stems and leaves
an organ that anchors a vascular plant
taproot system
consists of one main vertical root that develops from an embryonic root
lateral roots
develop from the taproot
fibrous root system
a mat of generally thin roots spreading out below the soil surface, with no root standing out as the main one
any plant part that grows in an unusual location
root hair
an extension of a root epidermal cell
an organ consisting of an alternating system of nodes and internodes
the points at which leaves are attached
the stem segments between nodes
axillary bud
a structure that has the potential to form a lateral shoot, commonly called a branch
terminal bud
includes developing leaves and a compact series of nodes and internodes
apical dominance
inhibiting the growth of axillary buds
the main photosynthetic organ of most vascular plants, consisting of a flattened blade and petiole stalk
the vascular tissue of leaves
tissue system
consists of one or more tissues organized into a functional unit connecting the organs of a plant
dermal tissue system
the outer protective covering
a single layer of tightly packed cells
protective tissues that replace the epidermis in older regions of stems and roots
a waxy coating that helps prevent water loss
vascular tissue system
carries out long-distance transport of materials between roots and shoots
conveys water and dissolved minerals
transports organic nutrients such as sugars
the vascular tissue of a root or stem
vascular cylinder
the form of the stele of the root in angiosperms
vascular bundles
strands consisting of xylem and phloem
ground tissue system
tissues that are neither dermal nor vascular
ground tissue that is internal to the vascular tissue
ground tissue that is external to the vascular tissue
the cell contents exclusive of the cell wall
indeterminate growth
growth occurs throughout a plant's life
determinate growth
growth that ceases after reaching a certain size
plants that complete their life cycle in a single year or less
generally live two years
plants that live many years
perpetually embryonic tissues
apical meristems
provide additional cells that enable the plant to grow in length (primary growth)
herbaceous plants
nonwoody plants
lateral meristems
causes growth in thickness (secondary growth)
vascular cambium
lateral meristem that adds layers of vascular tissue called secondary xylem and secondary phloem
cork cambium
lateral meristem that replaces the epidermis with periderm, which is thicker and tougher
cells that remain as sources of new cells
cells that continue to divide until the cells they produce become specialized within developing tissues
primary plant body
the parts of the root and shoot systems produced by apical meristems
root cap
a root part that protects the apical meristem as the root pushes through the soil during primary growth
zone of cell division
includes the root apical meristem and its derivatives
zone of elongation
when root cells elongate
zone of maturation
when cells complete their differentiation and become functionally mature
the innermost layer of the cortex/a cylinder one cell thick that forms the boundary with the vascular cylinder
the outermost cell layer in the vascular cylinder, from which lateral roots arise
leaf primordia
finger-like projections along the flanks of the apical meristem, from which leaves arise
allow CO2 exchange between the surrounding air and the photosynthetic cells inside the leaf
guard cells
regulate the opening and closing of stomata
the region between the upper and lower epidermis/consists mainly of parenchyma cells
palisade mesophyll
consists of one or more layers of elongated cells on the upper part of the leaf
spongy mesophyll
below the palisade mesophyll
leaf traces
connections from vascular bundles in the stem
bundle sheath
a protective vein enclosing which consists of one or more layers of cells
secondary plant body
consists of the tissues produced by the vascular cambium and cork cambium
fusiform initials
produce elongated cells such as the tracheids, vessel elements, and fibers of the xylem
ray initials
initials which are shorter and oriented perpendicular to the stem or root axis, and produce vascular rays
older layers of secondary xylem
outer layers of xylem
small raised aresas of the periderm which enable living cells within a woody stem or root to exchange gases with the outside air
includes all tissues external to the vascular cambium
the development of body forma and organization
systems biology
An approach to studying biology that aims to model the dynamic behavior of whole biological systems.
asymmetrical cell division
one daughter cell receives more cytoplasm than the other during mitosis
pattern formation
the development of specific structures in specific locations
positional information
signals that continuously indicate to each cell its location within a developing structure
the condition of having structural differences at opposite ends of an organism
phase changes
the morphological changes that arise from transitions in shoot apical meristem activity
meristem identity genes
associated with the transition from vegetative growth to flowering
organ identity genes
genes that regulate the development of the characteristic floral pattern