Comments on: What is the definition of nutrition and structures in Science? http://www.juicefountainreviews.com/blog/nutrition/what-is-the-definition-of-nutrition-and-structures-in-science Living a Healthy Lifestyle for Less Thu, 04 Mar 2010 05:13:59 -0600 http://wordpress.org/?v=2.8.4 hourly 1 By: omega http://www.juicefountainreviews.com/blog/nutrition/what-is-the-definition-of-nutrition-and-structures-in-science/comment-page-1#comment-186 omega Fri, 29 Jan 2010 07:30:59 +0000 http://www.juicefountainreviews.com/blog/nutrition/what-is-the-definition-of-nutrition-and-structures-in-science#comment-186 The five-kingdom classification of organisms Nomenclature: Naming of organisms Binomial: Biological name of an organism → Genus species Taxon: Set of organisms within a category / Taxonomy / Study of biological classification Different levels of taxons: SPECIES, GENUS, FAMILY, ORDER, CLASS, PHYLUM, KINGDOM Most number of species on right Most similar organisms on left Unicellular: Single cell; Colonial: Groups of cells; Multicellular: Many cells Autotrophs produce energy from inorganic sources Phototrophs from photosynthesis/sunlight Chemotrophs from simple inorganic (oxidative) processes Heterotrophs digest and absorb organic molecules Prokaryotae (prokaryotes) Cell structure: Prokaryotes, unicellular Prokaryotes lack cytoplasmic organelles found in eukaryotes Cell wall: murein Nutrition: autotrophic (photosynthesis, chemosynthesis), aerobic heterotrophs Divide by binary fission, not by mitosis ≈10μm in size (bacterial cell, filaments of blue-green bacteria) Mutualistic nitrogen-fixing bacteria live in nodules on the root of legumes / symbiotic Protoctista (protoctists) Cell structure: eukaryotes, unicellular and multicellular Cell wall: (sometimes) polysaccharide Nutrition: autotrophic, heterotrophic Placed in this category by exclusion / cannot be placed in any other kingdom Slime moulds / fungi characteristics Protozoa / heterotrophic and ingest food Algae / photosynthesis ≈10μm (amoeba) - 1m (Laminaria / large brown alga) Fungi Cell structure: eukaryotes, multicellular and unicellular (yeast) Cell wall: chitin Nutrition: heterotrophic / saprotrophic decomposers or parasitic Genus Penicillium Body of a fungus is composed of thin filaments called hyphae / form a mycelium Secret enzymes / external digestion / absorbs resulting nutrients Erect hyphae that grow upwards from the mycelium carry their reproductive spores Chains of spores on the erect hyphae / coloured mould visible on stored food Break down organic matter Plantae (plants) Cell structure: only multicellular, eukaryotic; large vacuoles Cell wall: cellulose Nutrition: autotrophic (photosynthetic) Growth is restricted to meristems (layers/patches of dividing cells) Non-motile; adapted to land / strong tissues, leave gas exchange system, waterproofed Eg mosses, ferns, conifers, angiosperms (flowering plants) Plant kingdom has two different types of adults in their life cycle Gametophytes, hidden in plant / sexual reproduction forms multicellular zygotes Sporophytes, what we call plant / asexual reproduction to form spores that germinate into gametophytes Gametophyte (n) → gamete (n) → fertilisation → zygote (2n) → mitosis → sporophyte (2n) → meiosis → spore (n) → mitosis → gametophyte (n) Animalia (humans, animals) Cell structure: eukaryotic, multicellular, no cell wall Develop form a blastocyst / embryo Have nervous and hormonal control systems No cell wall! Nutrition: heterotrophic, involving a digestive system Are motile and grow throughout tissues (no mersitems)<br><b>References : </b><br> The five-kingdom classification of organisms
Nomenclature: Naming of organisms
Binomial: Biological name of an organism → Genus species
Taxon: Set of organisms within a category / Taxonomy / Study of biological classification
Different levels of taxons: SPECIES, GENUS, FAMILY, ORDER, CLASS, PHYLUM, KINGDOM
Most number of species on right
Most similar organisms on left
Unicellular: Single cell; Colonial: Groups of cells; Multicellular: Many cells
Autotrophs produce energy from inorganic sources
Phototrophs from photosynthesis/sunlight
Chemotrophs from simple inorganic (oxidative) processes
Heterotrophs digest and absorb organic molecules

Prokaryotae (prokaryotes)
Cell structure:
Prokaryotes, unicellular
Prokaryotes lack cytoplasmic organelles found in eukaryotes
Cell wall: murein
Nutrition: autotrophic (photosynthesis, chemosynthesis), aerobic heterotrophs
Divide by binary fission, not by mitosis
≈10μm in size (bacterial cell, filaments of blue-green bacteria)
Mutualistic nitrogen-fixing bacteria live in nodules on the root of legumes / symbiotic

Protoctista (protoctists)
Cell structure: eukaryotes, unicellular and multicellular
Cell wall: (sometimes) polysaccharide
Nutrition: autotrophic, heterotrophic
Placed in this category by exclusion / cannot be placed in any other kingdom
Slime moulds / fungi characteristics
Protozoa / heterotrophic and ingest food
Algae / photosynthesis
≈10μm (amoeba) – 1m (Laminaria / large brown alga)

Fungi
Cell structure: eukaryotes, multicellular and unicellular (yeast)
Cell wall: chitin
Nutrition: heterotrophic / saprotrophic decomposers or parasitic
Genus Penicillium
Body of a fungus is composed of thin filaments called hyphae / form a mycelium
Secret enzymes / external digestion / absorbs resulting nutrients
Erect hyphae that grow upwards from the mycelium carry their reproductive spores
Chains of spores on the erect hyphae / coloured mould visible on stored food
Break down organic matter

Plantae (plants)
Cell structure: only multicellular, eukaryotic; large vacuoles
Cell wall: cellulose
Nutrition: autotrophic (photosynthetic)
Growth is restricted to meristems (layers/patches of dividing cells)
Non-motile; adapted to land / strong tissues, leave gas exchange system, waterproofed
Eg mosses, ferns, conifers, angiosperms (flowering plants)

Plant kingdom has two different types of adults in their life cycle
Gametophytes, hidden in plant / sexual reproduction forms multicellular zygotes
Sporophytes, what we call plant / asexual reproduction to form spores that germinate into gametophytes
Gametophyte (n) → gamete (n) → fertilisation → zygote (2n) → mitosis → sporophyte (2n) → meiosis → spore (n) → mitosis → gametophyte (n)

Animalia (humans, animals)
Cell structure: eukaryotic, multicellular, no cell wall
Develop form a blastocyst / embryo
Have nervous and hormonal control systems
No cell wall!
Nutrition: heterotrophic, involving a digestive system
Are motile and grow throughout tissues (no mersitems)
References :

]]>