Two major groups of angiosperms: dicots and monocots
Root System: tap root vs. fibrous root
Leaf base: petiole vs. sheath
Lead venation: reticulate vs. parallel
Roots below the ground are equal to the amount of leaves above the ground
MTwo major groups of angiosperms:oot for food storage, propagation and defense and
mechanical support. (example: a potato grows tuber – modified stems to create more
Dicots and monocotspotato plants)
Pay attention to:
Root system: tap root
vs. fibrous root.
Leaf base: petiole vs.
reticulate vs. parallel
4 The dermal tissue system is the outer covering of the plant.
The ground tissue system carries out photosynthesis, stores photosynthetic products and
helps support leaves
The vascular tissue system conducts water and solutes throughout the plant
Girth (diameter) of plant increased by secondary growth
Increase in plant height by primary group of the meristem
Vascular Bundles in Stems:
In a cross-section of the stem, vascular bundles are arranged differently in dicots
(in a ring) and monocots (scattered).
In dicots, cambium of adjacent vascular bundles gets joined forming a cambial
ring. The cell division activity of the cambial ring forms sec xylem towards inside
sec phloem towards outside, constituting secondary growth.
You can determine the age of a tree by counting the number of rings in its cross
section. of a tree gives its. How old is this tree? Within an annual ring, cells
formed during wet season are larger than cells formed during drier season.
Thus an examination of annual rings in tree cross- sections can tell us about past
Phloem is smaller and living, unlike xylem
^ this is secondary growth
Increase in stem diameter by secondary growth which gives rise to concentric annual
rings: Age of a tree, cells formed during wet season are larger than cells formed during
Internal structutre of primary rootll us about past climates
Internal Structure of Primary Root:
Note the difference in
the arrangement of
vascular system in a
dicot and a monocot
7 Simple and Compound Leaves:
How can you tell a simple leaf from a leaflet of a compound leaf? Simple leaves are
those with a single blade. Some compound leaves consist of leaflets arranged along a central
axis. Further division of the axis results in a doubly compound leaf.
Compound: no bud in the leaflets, that’s how you distinguish a leaf from a
Stoma: more common on the lower surfaces
Diffusion and Osmosis:
Diffusion is movement of molecules due to their internal thermal/kinetic
Osmosis is diffusion across a selectively permeable membrane
o Hypertonic: on the outside (concentrate solutes outside)
o Isotonic: equivalent solute concentration
o Hypotonic: on the outside (dilute solutes outside)
Selectively permeable vs. semi-permeable
Movement of water and mineral ions from the soil to the root xylem: apoplastic
(material passes through meshwork of the cell walls and extracellular
spaces without crossing the plasma membrane) and symplastic (continuous
meshwork of the interiors of living cells in the plant body, resulting from the
presence of plasmodesmata; cytoplasmic strand connecting two cells)