MAIN CAMPUS
COLLEGE OTHER NATURAL SCIENCE
TITLE COURSE… Introduction to Botany & Zoology
COURSE…… General Biology (Biol 1012)………..
Individual Assignment
DEMERE TAKELE MAMO
IDNO: NaScPT3398/14
SECTION 7
January 2015
Hawassa Ethiopia
1 State morphological variations in Algae
Algae are placed in Kingdom Protista along with protozoa. Earlier they were classified with plants as they
are photosynthetic autotrophs-possess chlorophyll and chloroplasts and superficially appear like plants.
Since their gametes do not have protective cells around them they are no longer classified with plants.
Their size ranges from simple microscopy to giant thallus extending several meters in length as in kelps.
Algal morphology varies from simple unicellular form to complex thallus as found in seaweed.
The form and structure of algae sets them apart from plants. Although algae and plants both contain
chlorophyll and photosynthesize, algae don’t have an actual root system, stem or leaves. Algae cells
are typically simpler than plant cells and have fewer organelles in their cell cytoplasm. Algae are often
distinguishable both their color Algae are widely distributed in nature whenever there is plenty of water
and sunshine. They also occur abundantly on wet rocks, wet ground, and a pool of water. They also
inhabit harsh habitats. The body of an alga is called the thallus. Morphologically algae can be
distinguished as unicellular, colonial, filamentous, heterotrichous, thalloid, and polysiphonoid forms
(Amal Alghamdi 362 mic (2014) algal structure Department of Botany and Microbiology)
Unicellular Algae: are motile e.g. Chlamydomonas species, Euglena species Non-motile e.g. Chlorella
species
Multicellular Algae: Have large, complex, leaf-like thallus. Ulva species
Filamentous Algae: are single algae cells that form long visible chains. Example Spirogyra species
Chlamydomonas species unicellular, motile cells. Cup-shaped chloroplast, with pyrenoids
Chlorella species Unicellular, non-motile cells, Cup-shaped chloroplast, with pyrenoid.
Some algae have three dimensional state found like in brown, red and green algae
2 Write the different divisions of algae with their examples
1 Chlorophyta (Green Algae) the colors of Chlorophyta range from Green to Orange. The orange color is
due to Carotenoids which form the Accessory Pigments for this Division. Their Photosynthetic
Pigments are Similar to those of Vascular PlantChlorophyll a, b are typically present along with a,
b Carotene plus Xanthophylls.e.g Trentepohlia eljunque,Untroden snow, devid webb
2 Cyanophyta (Blue-Green Algae) s a group of photosynthetic bacteria widely distributed in various
aquatic habitats (oceans, seas, rivers, lakes, etc.) and terrestrial habitat with approximately 2,000
species, cyanobacteria are a highly diverse phylum belonging to the kingdom of bacteria. Spirulina,
Anabaena, Nostoc, Oscillatoria.
3 Chrysophyta(Golden-brown, Diatoms); The plant-like or algal species are further divided into the
following phyla: Euglenophyta, Chrysophyta (diatoms), Pyrrophyta (dinoflagellates), Chlorophyta, (green
algae), Phaeophyta (brown algae), and Rhodophyta (red algae). Chrysophyta includes the chrysophytes or
the Chrysophyceae (golden algae), Pascher, A. (1914). “Über Flagellaten und Algen “. Berichte der
deutsche botanischen Gesellschaft 32: 136–160. 4 Rhodophyta (Red Algae), 5 Euglenophyta
(Euglenoids) 6 Cryptophyta (Cryptomonads7 Xanthophyta(Yellow-Green algae),
8Charophyta(Stoneworts)e.tc
3 List the classes of bryophytes and pteridophytes; and describe the major characteristics
of Psilophytes & Lycophytes.
1 Hepaticopsida The classification of Bryophytes is incomplete without Hepaticopsida. Here are some of
this class’s salient features. Several chloroplasts are present in each thallus cell. However, chloroplasts are
devoid of pyrenoids. Columella is absent in the capsule. Reproductive organs are embedded within the
dorsal surface. Septa absent in rhizoids.
2 Anthocerotopsida also called horned liverwort, any of about 300 species of small nonvascular plants.
Hornworts usually grow on damp soils or on rocks in tropical and warm temperate regions. The
largest genus, Anthoceros, has a worldwide distribution
3 Bryopsida This class of Bryophytes contains nearly 1500 species, making it the largest class among the
three. Also known as mosses, common examples of Bryopsida include polytrichum and funaria, among
others. Bryophyta includes embryophytes like mosses, hornworts, and liverworts. These are the plants
that grow in shady and damp areas and are small in size. They lack vascular tissues. They reproduce
through spores instead of producing flowers and seeds. Despite the fact that most bryophytes lack
complex tissue organization,
Psilopsida; In psilopsida plants have rootless sporophytes. The stem is differentiated into an underground
rhizome and an aerial part. Both are dichotomously branched. The rhizome bears rhizoids, both perform the
function of root. The aerial branches are green, leafless and bear small veinless out growths and carry
out photosynthesLycopsida
Class of the Pterido-phytina, represented today by relatively small plants, the club mosses, although in
the Carboniferous they included large trees which dominated the coal-swamp vegetation of the time. The
oldest lycopods date from the Devonian and derived from the most primitive of vascular plants, the
1 Sphenopsida appeared in the Devonian and reached the peak of its abundance and diversity during
the Carboniferous, forming a major component of the coal-swamp vegetation. Sphenopsids are
characterized by jointed stems with whorls of leaves and branches borne at the joints (or nodes)
2 Pteropsida; The delicate, varied and highly attractive foliage of ferns have made them a must in any
garden. Of all the pteridophytes, ferns are the most widely distributed. The living ferns are represented by
305 genera and nearly 10,000 species. Bryophytes are non-vascular plants, without xylem and phloem.
They may reproduce both sexually and vegetatively. For examples, liverworts and hornworts. On the
contrary, pteridophytes are vascular plants with xylem and phloem.The dominant phase in pteridophyte is
the sporophyte. Ferns, spikemosses, quillworts are a few pteridophytes. Let us explore some of the major
difference between bryophytes and pteridophytes.
Bryophytes are non-vascular plants.
The plant body is leafy or thalloid.
Pteridophytes are vascular plants.
The plant body is differentiated into roots, stem
Cells are haploid.
Cells are diploid.
The gametophyte is dominating.
The sporophyte is dominating
Mosses, liverworts, hornworts,
Spikemosses, ferns, quillworts,
4 What are the major features of seed plant
Seed plants produce pollen and live on land, Plants that produce seeds as offspring are known as "seedbearing plants." Because they produce both male and female spores, all seed plants are hetero sporous.
Seed-producing plants require the retention of mega sporangium angiosperm ovule the extant seed
plants are monophyletic in recent plant phylogenies with ovules, and the resulting seeds and seed embryo
cotyledon and germination root cap.
5 Identify key features of invertebrate groups; & differentiate the characteristics of vertebrates
There are seven primary groups of invertebrates in the animal kingdom. They are sponges, ctenophores,
cnidarians, echinoderms, worms, mollusks and arthropods.
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All invertebrates do not have a spinal cord or vertebral column, instead, most of them possess an
exoskeleton that encompasses the entire body.
Normally, these are tiny and don’t grow very large.
Do not possess lungs since they respire through their skin.
Since they cannot produce their own food, Invertebrates are heterotrophic.
Reproduction occurs through fission
Vertebrate organisms have
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5
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Well Developed brain
Brain is covered with cranium
Partially open circulatory system.
Two pairs of appendages
Notochord, forms on the dorsal side of the primitive gut in the early embryo.
Pharyngeal slits connect the pharynx that links the mouth cavity and the esophagus, w
Vertebrates are characterized by the presence of a vertebra or backbone; a skull; skeletal bones that form
an endoskeleton; a bilaterally symmetrical structure; and two pairs of appendages, such as fins, limbs or
wings. Vertebrates’ organ systems are more developed than those of invertebrates, and their nervous
systems are more complex.
Reference
Agric4profits.com, October 22, 2022 plant section The Different Forms and Morphology of Algae.
(Amal Alghamdi 362 mic (2014) algal structure Department of Botany and Microbiology).
Psilopsida (Psilophyta January 4, 2020 Editorial Staff Biology(online biology).
psilophytesLycopsida | Encyclopedia.com ,Sphenopsida | Encyclopedia.com
http://www.com/Pteropsida: Plant Body and Classification |
Botany.http://www.toppr.com/guides/biology/plant-kingdom/pteridophytes.
http://www.letshealthify.com/what-are-the-characteristics …