Biology Questions and Answers
- What are vascular
bundles? How does the
configuration of the vascular
bundles within the stem
differentiate monocots from
dicots?
Vascular bundles are segments of xylem
and associated plongitudinally within thhloem that re stem. Iun (^) n dicots
the vascular bundles are organized side-
by-side monocotsforming concentric the vascular bundles are rings. In
scattered and do not form rings.
- What are the main plant
tissues that form the rings
observed on stem sections of
some trees?
The rings observed on a stem crosssection of dicot trees are made of
conductive tissues: xylem and phloem.
- How can the age of a tree
be estimated from the
analysis of the rings present
on a cross section of its stem?
For the growth of the tree it is
necessary to havvessels within the stem, a taske formation of new
performed by the vascular cambium.
The vascularhot seasons (summ cambium is morer and spring)e active in
generating a lighter band made of largecalibered vessels. During winter and fall (^)
the vascular cambium produces the
opposite, so smalla darker band appears outsid calibered vessels ande the
previous lighter band. Therefore two
ring bands are made yearly, oand the other darker. By a direct countne lighter
of these band pairs one can estimate
the age of the tree.
- What are the plant tissues
that constitute the functional
structures of the leaf veins?
Leaf veins are made of vascular tissues.
They are constituted by phloem that respectively conxylem aduct waternd (^)
and mineral n(phloem). utrients (xylem) and sugar
- Which are the plant
tissues specialized in
covering?
The coverinof the plants are the epidermis (thatg tissues, or dermal tissues,
covers the leaves and the young stems
and shoots) and the periderm (a tissuethat substitutes the epidermis in stems, (^)
shoots and roots). The periderm is
made of phelloderm, psuber (cork). hellogen and
- Which are the plant
tissues that cover the stem
and the leaves?
The stem may b(having stomata,e covered by epidermis cuticle and
photosynthalternatively,etic cells) as in monocots or, the epidermis is
substituted by the periderm
http://www.biology-questions-and-answers.com