Topic 1 - CLASSIFICATION OF
LIVING THINGS
TOPIC
1: CLASSIFICATION
OF LIVING THINGS
Kingdom
Fungi
Member of the kingdom Fungi include fairly familiar
organisms such as mushrooms, toadstools and bracket fungi. There are also less
obvious but very important members such as mold, which grow on bread, ripe
fruits and other food.
The
General and Distinctive Features of the Kingdom Fungi
Explain
the general and distinctive features of the kingdom Fungi
General
features of kingdom fungi
§ Fungi are found in damp or wet places
§ They have eukaryotic cells with a rigid protective
wall made of chiti
§ They are heterotrophs, some are saprophytic where
others are parasitic
§ They store food as glycogen
§ They reproduce using spore
§ They are non-mobile
Distinctive features of kingdom fungi
§ They have chitin in their cell wall
§ They have septate
The
Phyla of the Kingdom Fungi
State
the phyla of the Kingdom Fungi
Phyla of the kingdom fungi
§ Ascomycota
§ Zygomycota
§ Basidiomycota
Ascomycota
Ascomycota are also called sae fungi. They produce
spore in sae-like cell called asei. These spores are called ascopores. Examples
of Ascomycota are bakers’ yeast, cup fungi and ring worm fungi.
Characteristics
of phyla Ascomycota
§ Their cell wall is not made by chitin but cetin
polysaccharide component of phosphoric acid
§ Have granulated cytoplasm
§ Store food in form of glycogen
§ Reproduce asexually by budding and sexually by
means of ascospores.
Distinctive features
§ Reproduce sexually by means of ascospores
The
Structure of Mosses
Mosses are small, soft plants called bryophytes,
that are typically 1–10 cm (0.4–4 in) tall, though some species are much
larger. They commonly grow close together in clumps or mats in damp or shady
locations. They do not have flowers or seeds, and their simple leaves cover the
thin wiry stems. At certain times mosses produce spore capsules which may
appear as beak-like capsules borne aloft on thin stalks.
Advantage and Disadvantages of Mosses
Outline
advantage and disadvantages of Mosses
On the advantage side, it can help to hold the
bonsai soilin place and prevent it from washing out of the container. Moss can
increase the water retention capability of the soil by slowing evaporation.
On the disadvantage side, a thick carpet of moss
can reduce the diffusion of gases into the soil and to the roots, which can
result in root rotor poor drainage conditions. Moss can grow up onto the
surface roots and trunk of your bonsai, and soften their bark, promoting its
decay.
Division
Filicinophyta (Pteridophyta)
General
and Distinctive Features of the Division Filicinophyta
Explain general and distinctive features of the
division Filicinophyta
This division was formerly called Pteridophyta. The
division Filicinpphyta includes a group of primitive vascular plants. The adult
plant body in these plants is a sporophyte. It shows differentiation into true
roots, stems and leaves. The stem is mostly herbaceous. Leaves may be smaller
or larger. Vascular tissues are present in all the vegetative parts of the
plant body.
Characteristics of division Filicinophyta
Members of this kingdom include horsetails, ferns
and mosses.
§ Reproduction involves production of spores inside
special structures called sporangiawhich occur on the underside of the leaves
called sporophylls. Sprangia may sometimesbe found in groups called sori.
§ The plants may be homosporous - producing only one
type of spore or heterosporous -producing two different types of spores;
smaller microspores and larger megaspores.
§ They are seedless vascular plants, which contain
vascular tissues but do not produceseeds.
The
Structure of Ferns
Ferns are intermediate in complexity
between the more primitive bryophytes (mosses, liverworts, and hornworts) and
the more advanced seed plants. Like bryophytes, ferns reproduce sexually by
making spores rather than seeds. Most ferns produce spores on the underside or
margin of their leaves. Like seed plants, ferns have stems with a vascular
system for efficient transport of water and food. Ferns also have leaves, known
technically as megaphylls, with a complex system of branched veins.
In general,
ferns consist of the following structures:
Fronds
The frond is the "leaf" of a fern. It is
divided into two main parts, the stipe (leaf stalk or petiole)and the blade
(the leafy expanded portion of the frond).
Rhizomes
Rhizomes would be comparable to "stems"
in the flowering plants. Fronds arise from therhizome. In some epiphytic ferns
(ferns that grow on trees) and in terrestrial creeping ferns therhizome roams
widely and is quite visible.
The rhizome contains the conducting tissues (xylem
and phloem) and the strengthening tissues (sclerenchyma fibres). The conducting
tissue, known as the vascular bundle, carries the water, minerals, and
nutrients throughout the plant.
Roots
Roots are formed from the rhizomes or sometimes
from the stipe. The roots usually do not divide once they grow from the
rhizome. Tree fern roots grow down from the crown and help thicken and
strengthen the trunk. The roots anchor the plant to the ground and absorb water
and minerals.
Sporangia
The sporangia are the reproductive structures of
the ferns and fern allies. They produce the dust like spores that are the
"seeds" by which ferns are propagated. Several sporangia grouped
together are called a sorus. Most ferns have their sporangia on the underside
of the frond, arranged in an organized pattern usually associated with veins in
the pinnule (leaf). Many times(but not always) the ferns provide a protective
covering for the sorus called an indusium
Spores
The "seeds" of the ferns and fern allies
are called spores. Normally they are formed in groups of four. Spores contain
oil droplets and sometimes chlorophyll in their nucleus.
Advantages
and Disadvantages of Ferns
Advantages
of ferns
§ Some ferns are edible and hence serve as a source
of food.
§ They provide nutrients to the soil to improve soil
fertility.
§ They cover the soil and prevent soil erosion.
§ They are used as decoration materials.
Disadvantages of ferns
§ They harbour dangerous organisms like snakes and
insects.
§ Some ferns are poisonous when eaten.