Download SBI 3U: VASCULAR PLANT TISSUES NAME: Please answer these

SBI 3U: VASCULAR PLANT TISSUES
NAME: _________________________
Please answer these questions using the ppt notes from today as well as the information given below to help you out.
1.
In this unit, we examine vascular plants. What is the difference between vascular and non-vascular plants?
Photosynthesis, the process by which plants synthesize their own carbohydrates, is the most important distinguishing feature of the plant
kingdom. It is these carbohydrates which supply both stored chemical energy and building blocks for cell growth and reproduction. They also
provide the food for all other organisms through food webs. Photosynthesis is a cellular process. How do plants, like angiosperms (plants that
flower), ensure that their green cells receive the sunlight, carbon dioxide and water needed for photosynthesis? How do they distribute the
manufactured carbohydrates to all their cells? How do plants store these products? We will examine these questions over the next few days.
2.
What is photosynthesis? Why is it vital to the survival of plants? What are the reactants (starting substances) needed for photosynthesis
and what products are created from this process?
Cells of all multicelluar organisms are organized into tissues, tissue systems, organs and organ systems. A tissue is a group of cells, usually
identical, that act together to carry out a specific function. These structures enable plants to successfully photosynthesize, grow and
reproduce. The 2 main organ systems of a plant are the root system and the shoot system. Please examine the picture below to note these
systems as well as various tissues and organs on the plant. Note that not all plants will have all the parts shown nor will parts with similar
functions look the same from species to species.
SHOOT SYSTEM
ROOT SYSTEM
3.
What is a meristem? What are apical and lateral meristems, and what results from their activity?
Primary growth includes all growth in the length of roots and stems throughout a plant’s entire life and all growth in the diameters of rots and
stems which occurs in the first year of a plant’s life. Secondary growth is the result of lateral meristem activity; it results in increased diameters of
roots and stems in the second and all subsequent years of a plant’s life.
Plant tissues are specialized for functions such as absorption, transport, storage, photosynthesis, and reproduction. There are 3 major types of
plant tissue – dermal tissue, ground tissue and vascular tissue – which are distributed throughout the plant body. Dermal tissue cells are found in
the epidermis and the periderm. The epidermis is the outermost cell layer of a multicellular plant experiencing primary growth. Periderm is a
protective covering that replaces the epidermis in plants that show extensive secondary growth. Epidermal tissue often contains highly specialized
cells such as root hair cells and leaf guard cells, that help with water distribution in the plant. During secondary growth in roots and stems, the
epidermis is replaced by the periderm. Some peridermal cells form many layers of special cells that soon die but leave behind a material that
waterproofs the roots and stems and protects the inner tissues from structural damage. Ground tissue cells, the second major type of plant tissue,
make up all of the internal nonvascular regions in the plant. Vascular tissue cells, the third major type of plant tissue, are specialized for
conducting materials throughout the plant body.
4.
Where are dermal tissue cells found? What type of role do they have on the plant?
5.
Fill in the following chart:
SUMMARY OF GROUND TISSUE
Parenchyma cells
Function of
these cells
Sketch &
Label a
longitudinal
view of these
cells
Collenchymas cells
Sclerenchyma cells
VASCULAR TISSUE
Xylem conducts water and dissolved minerals (together called xylem sap) from the roots to all parts of the plant. There are two types of xylem
cells: vessels or vessel elements and tracheids. Vessels elements are only found in angiosperms. A vessel consists of many vessel elements
connected end-to-end. The ends are either absent or perforated which allows xylem sap to pass form one element to the next as it travels upward
through the length of the vessel. Vessels are often packed side-by-side and may be connected to each other. These permit the lateral flow of
xylem sap from one element to the next. Thus, xylem sap may flow straight upward or may change vessels part way by flowing laterally. Tracheids
are much narrower than the vessel elements and their ends are so sharply angled that they appear pointed. Tracheids are found in all vascular
plants, not just angiosperms.
The substances cellulose and lignin are deposited on the exterior surfaces of xylem cells to form rigid cell walls. When the cell walls are complete,
they cytoplasm dies, leaving dead, hollow xylem. They continue to transport water and dissolved substances until they get filled with various
deposits. Wood, no matter what kind, is comprised almost entirely of xylem tissue. In some woody plants, xylem cells eventually become plugged
with oils, gum, tannins and resin, resulting in the formation of heartwood.
WATER
FOOD
6.
Describe the main difference between xylem and phloem cells.
7.
Draw a diagram of the 2 types of water-conducting xylem cells.
8.
A microscopic view of a plant section reveals a greater than usual number of xylem cells. What might this suggest about the plant’s
ability to conduct and store water? In what kind of environment would a large number of xylem cells be beneficial to survival? Explain.
9.
Identifying and learning the names of plant tissues can be challenging, even for experienced plant biologists! Create a table OR a concept
map which lists the three major tissue types, the specific cell types in each, and their special structures (if given) and the function of these
types of cells. Use a different piece of paper to answer this question if you prefer.