Midterms Flashcards
- artificially uniting stems or parts of stems different but related varieties of plants has been practiced by humans for hundreds of years.
Grafting
Meristems at tips increases their length and other meristems increase their girth of hundred or thousand of years.
Intermediate growth
- leaves that are in whorls (groups of three or more).
Whorled
leaves attached are in pairs arranged
Opposite or oppositely arranged
leaves attached to the twig alternately or in spiral around the stem
Alternate or alternately arranged
- stem region between nodes
Internode
the area or the region of a stem where a leaf or leaves are attached.
Node
a twig by a stalk. A slender stem that supports the blade of the foliage leaf.
Petiole
flat expanded part of a leaf as distinguished from the
petiole. The leaf of an herb or grass.
Blade
this is where axil (angle between a petiole and stem containing a bud) are situated.
Axillary Bud
the area or the region of a stem where a leaf or leaves are attached.
Node
base of the petiole that are paired, often somewhat leaf-like, appendages that remain throughout the life of the leaf.
Stipules
loose aggregation of cells which penetrates the surface of a woody plant and through which gases are exchanged between the gases in the atmosphere and its tissues.
Lenticels
located at the tip of each twig. It resembles an axillary bud but is often larger. Produces tissues that make the twig grow larger.
Terminal Bud
There is an ________ at the tip of each stem that contributes to an increase in the length of the stem.
apical meristem
They are dormant before the growing season begins.
Apical meristems
(singular: primordium
Leaf primordia
- develop from a bud that begins to expand or seed germinates, the cells of the apical meristems undergo mitosis
Primary meristems
- tiny embryonic leaves that will develop into mature leaves after the bud scales drop off and growth begins.
Leaf primordia (singular: primordium)
the outermost part of the primary meristems that give rise to the epidermis.
Protoderm
cylinder of strands that is the interior of the periderm. It produces water-conducting primary xylem cells and primary phloem cells that have variety of functions like conduction of food.
Procambium
the parenchyma tissue in the center of the stem. Very large, and may break down shortly after they are formed, leaving a hollow, cylindrical area.
Pith
produces two tissues composed of parenchyma cells.
Ground Meristems
produced by the ground meristem may become more extensive but in woody plants, it, too, eventually will be crushed and replaced by new tissues produced from within.
Cortex
All the five tissues produced by this apical meristem complex (epidermis, primary xylem, primary phloem, pith and cortex arise while the stem is increasing in length and are called ______
primary tissues
What are the five tissues produced by this apical meristem complex arise while the stem is increasing in length and are called primary tissues
epidermis, primary xylem, primary phloem, pith and cortex
What develop into mature leaves and buds.
Leaf primordia and bud primordia
strand of xylem and phloem.
Trace
strand of xylem and phloem.
Trace
Narrow band of cells between the primary xylem and the primary phloem may retain its meristematic nature and become the
vascular cambium.
Each trace leaves gap filled with parenchyma in cylinder of vascular tissue, forming a
leaf gap or bud gap.
conducts water and soluble nutrients.
Secondary Xylem
conducts insoluble form, food
manufactured by photosynthesis throughout the plant.
Secondary Phloem
Secondary cambium arises in the cortex or some instances in the epidermis or phloem.
Cork cambium or phellogen
produces box-like cork cells which become impregnated with suberin (a waxy substance impervious to moisture). They are produced annually.
The cork cambium
In young stems, gas exchange takes place through
the stomata, located in the epidermis.
As woody stems age,what develop beneath the stomata.
lenticels
central cylinder that is composed of primary xylem, primary phloem and pith in most younger and a few older stems and roots.
Steles
simplest form consists of solid core of conducting tissues in which the phloem usually surrounds the xylem. Common in primitive seed plants that are now extinct and are also found in whisk ferns, club mosses and other relatives of fern.
Protostele
Three types of Protostele are:
Haplostele
Actinostele
Plectostele
tubular with pith in the center are common in ferns.
Siphonosteles
Three types pf Siphonostele:
Solenostele
Dictyostele
Eustele
seed that have one or two seed leaves.
Cotyledons-
flowering plants develop from seed having
two cotyledons
Dicotyledon
common in present day flowering plants and conifers. Primary xylem and primary phloem are in discrete vascular bundles.
Eusteles-
- develops from seeds with single cotyledon.
Monocotyledon
- plants that die after going from seed to maturity within one growing season, have green herbaceous stem. Most monocots are annuals.
Annuals
These have discrete vascular bundles composed of patches of xylem and phloem.
Herbaceous dicot stems
They are arranged in cylinder that separates the cortex from the pith.
Vascular bundles
relatively large vessel elements of secondary xylem that is produced when the vascular cambium of a typical broadleaf tree first becomes active in the spring.
Spring Wood
xylem that is produced after the spring wood, and which has smaller or fewer vessel elements and large number of tracheids
Summer Wood
One year’s growth of xylem is called an ______
annual ring
It may contain many layers of xylem cells and it is all the layers produced in one growing season that constitute an annual ring-not just the dark layers.
annual ring.
produces more secondary xylem than it does phloem.
Vascular cambium
They have stronger, more rigid walls and less subject to collapse from tension.
Xylem cells
It does not only indicate the age of the wood, but they can also tell something of the climate and other conditions that occurred during the tree’s lifetime.
Annual rings
fairly obvious lighter streaks or lines radiating out from the center across the annual rings when a tree trunk is examined in transverse, or cross section.
Vascular rays
Their function is for the lateral conduction of nutrients and water from stele through the xylem and phloem, to the cortex, with some cells storing food.
Vascular rays
part of ray within the xylem.
Xylem Ray
Consists of parenchyma cells that may remain alive for 10 or more years.
Vascular Rays
extension through the phloem.
Phloem Ray
protrusions due to the expansion of the protoplasm that leads to the cavity of the vessel or tracheids that prevent further conduction of water and dissolved substances-resins, gums, and tannins begin to accumulate, along with pigments that darken the color of the wood.
Tyloses
lighter, still-functioning xylem closest to the cambium.
Sapwood
Forms at roughly the same rate as heartwood develops.
Sapwood
older, darker wood at the center
Heartwood
older, darker wood at the center
Heartwood
True or false:
Pines and other cone-bearing trees have xylem that consists primarily of tracheids; no fibers or vessel elements are produced.
True
Woods are softer than that of trees with them and is commonly referred to as
softwood
True or false:
Pines and other cone-bearing trees have xylem that consists primarily of tracheids; with fibers or vessel elements are produced.
False
True or false:
Pines and other cone-bearing trees have xylem that consists primarily of tracheids; no fibers or vessel elements are not produced.
False - produced
the wood of woody dicot trees is called
hardwood
applied to all tissues outside the cambium including the phloem.
Bark
consisting of primary and secondary phloem.
Inner bark
consisting of cork tissue and cork
cambium.
Outer bark (periderm)
specialized cells or ducts that are found in about 20 families of herbaceous and woody flowering plants. Common in the phloem but occur throughout all parts of the plant.
Lactifiers
a thick fluid that is white, yellow, orange or red in color and consists of gum, proteins, sugars, oils, salts. alkaloidal drugs. enzymes and other substances.
Latex
They resemble vessels, from extensive branched networks of latex-secreting cells originating from rows of merismatic cells. Their cells remain living and have many nuclei.
Lactifiers
They resemble vessels, from extensive branched networks of latex-secreting cells originating from rows of merismatic cells. Their cells remain living and have many nuclei.
Lactifiers
Its function in the plant is not clear although some believe that it aids in closing wounds.
Latex
most important form of latex with commercial value, Amazon Indians utilized rubber for making balls and containers hundreds of years before Para rubber trees were cultivated for their latex.
Rubber
The concentration of bundles, combined with the band of sclerenchyma cells beneath the epidermis and the thicker-walled parenchyma cells, all contribute to giving the stem the capacity to withstand stresses resulting from summer storms and the weight of the leaves and the ears of corn as they mature
Monocotyledonous stems
wheat, rice, barley, oats, rye and other grasses have this that is at the base of each internode. It contributes to increasing stem length.
Intercalary meristem
True or False:
Palm trees which differ from most monocots in that they often grow quite large, do so primarily as a result of their parenchyma cells continuing to divide and enlarge without a true cambium developing.
True
True or false:
Monocot fibers are as strong or as durable as most dicot fibers.
True
Most higher plants have an __________, many species have specialized stems that are modified for various functions.
erect shoot system
All specialized stems have _______, _________,_________ which makes them different from roots and leaves.
nodes, internodes and axillary bud
True or false:
The leaves at the nodes of these specialized stems are often small and scalelike. They are seldom green, but full-sized.
True
Horizontal stems that grow below ground, often near the surface of the soil.
Rhizomes
Adventitious roots are produced all along the rhizome, mainly on the lower surface.
Rhizomes
In strawberries, these are usually produced after the first flowers of the season have appeared.
runners
May radiate out from the parent plant and within a
few weeks may grow 1 meter or more long.
Runners and stolons
They superficially resemble roots, but close examination will reveal scale -like leaves and axillary buds at each node, at least some stage of development, with short to long internodes in between.
Rhizomes
Similar to runners but are produced beneath the surface of the ground and tend to grow in different directions (not horizontally).
Stolons
May be relatively thick, fleshy, food-storage organ, as in irises, may be quite slender, as in many perennial grasses or some ferns.
Rhizomes
In ____________, tubers are produced at the tip of the stolons.
Irish potato plants
In Irish or white potato plants, several internodes at the tips of stolons become tubers as they swell from accumulation of food.
Tubers
True or false:
In Irish potato plants, tubers are produced at the tip of the stolons.
True
They becomes isolated after the stolon to which it was attached dies.
mature tuber
The “eyes’’ of the potato are actually _________ formed in a spiral around the thickened stem. Each eye consists of an axillary bud in the axil of a scalelike leaf.
nodes
The “eyes’’ of the potato are actually nodes formed in a spiral around the thickened stem. Each eye consists of an __________ in the axil of a scalelike leaf.
axillary bud
Large buds surrounded by numerous leshy leaves, with a small stem at the lower end.
Bulbs
Resemble bulbs but differ from them in being composed almost entirely of stem tissue, except for a few papery, scalelike leaves.
Corns
Adventitious roots grow from the bottom of the stem, but fleshy leaves comprise the bulk of the bulb tissue which stores food.
● Onions, lilies, hyacinths and tulips.
Bulbs
Adventitious roots are produced at the base, and corms, like bulbs, store food
Corns
Flattened and appear leaflike.
Cladophylls (Cladodes or Phylloclades)
The feathery appearance of asparagus is due to
numerous small _____
cladophylls.
honey locust, whose branched thorns may be more than 3 decimeters, but all thornlike objects are not necessarily modified stems.
Thorns
base of the petiole of most leaves of the black locust
Spines
Occur in greenbriers, certain orchids, prickly pear
cacti and other less-known plants.
Cladophylls (Cladodes or Phylloclades)
simply rest on the tops of other plants.
Ramblers
e.g. grape and Boston ivy (specialized
stems), peas and cucumbers (modified leaf or leaf parts)
Tendrils
In a living tree, up to 50% of the weight of the wood is from the _________.
water content.
True or false:
In a living tree, up to 75% of the weight of the wood is from the water content.
False- 50%
Before the wood can be used, seasoning reduces the moisture content 10 10% or less, either by air-drying it in ventilated piles or stacks by dying it in special ovens known as ________.
kilns
The dry part of wood is composed of: cellulose
lignin
60%-75% cellulose
15-25%- lignin
a group of cells performing similar functions.
Tissues
True or False:
A plant organ may compose of several different tissues; each tissue is classified according to its structure, origin and function.
True
Three basic tissue that occur in roots and stems:
- Woody dicots
- Herbaceous dicots
- Monocots
Composed of cells whose primary function is the formation of new cells.
Merismatic tissues
Have thin walls and easy to divide.
Merismatic tissues
