Recognise plants, Topic 3: Plant morphology. part 1 roots, stems and leaves Flashcards
lable all parts
What is the Function of the following Organs:
Roots, stems, leaves, flowers, fruit,
The main type of root systems include:
tap roots
fibrous roots
adventitious roots
Describe tap roots:
A carrot is an excellent example of a tap root
system. The big fleshy orange part is the primary root (the one that initiated when the seed
sprouted) , the smaller roots growing from this are the secondary roots.
Tap roots occur in dicotyledonous and coniferous plants grown from seed. However a prominent primary root like that of a carrot usually only occurs in the early stages of growth. These large and very obvious swellings of the primary root do not persist for long. In fact, large trees have a radiating system of woody roots confined to the topsoil (where the air is). They do not usually have a big woody taproot plunging to the centre of the earth!
Lable the following stem.
What is a NODE?
- Node
The node is the region of the stem where the leaf is attached and the axillary bud is found in the junction of the leaf and the stem. In some species there may be two or more leaves attached at each node, and consequently, the same number of axillary buds as there are
leaves.
What are Lenticles
Lenticels are small pores in the bark of the stem which allow for diffusion of gases into and out of the stem. Even in winter the living cells of a dormant plant have a low rate of respiration continuing and this requires oxygen and releases carbon dioxide. Lenticels are found in many young stems and are often a prominent feature of deciduous species (such as Betula species (silver
birch) and some Prunus species).
Label the following:
What is used more than any other feature in plant identification and recognition?
Lamina or Blade
Define Axillary Bud and tell why it is important.
This is not actually part of the leaf, but the location of this bud is important in recognising the difference between simple and compound leaves. It will always be found above the petiole (or leaf base if the leaf is sessile) on the stem, in the axil of the leaf and the stem. Sometimes the bud will be a little shoot and can be then be called an axillary shoot.
Note the position of the axillary bud. It is still located in the axil of the petiole and stem. This is a very important feature to remember as it is the most accurate, and easiest, way to distinguish between compound and simple leaves. There are no axillary buds where each leaflet is attached to the rachis.
Lable the compound leaf
Define Antrorse
Pointing towards the apex or growing point.
