Microbiology

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Ch. 1
Prokaryotes = bacteria , archaea
Eukaryotes = Fungi, protozoa , algae (Growth:: Mitosis有絲分裂)

Bacterial cell → Bacillus(rodlike) , cocus (spherical), spiral (curved) *P.S. 有時會star-shaped or square → 出現既形式: pairs, chains, clusters cell walls of bacteria → peptidoglycan (carbohydrate & protein complex) cell walls of plant and algal cell → cellulose

Growth::Binary fission = bacteria reproduce by dividing into two equal cells bacteria 吸收nutrients from dead / living organisms/ photosynthesis / inorganic substance 佢地可以swim by moving flagella

Archaea
if 佢地有cell wall → lack peptidoglycan
Found in extreme environments
-Growth:: Binary fission
-cell wall → peptidoglycan
分3 main groups → methanogens + extreme halophiles + extreme thermophiles Methanogens → produce methane
Halophiles → live in extreme env. eg. The Dead Sea
Thermophiles → live in hot sulfurous water eg. Hot springs at Yellowstone National Park

Fungi
Cells hv a district nucleus = DNA
surrounded by special envelope(lipid membrane) = nuclear membrane unicellular(eg. yeast) / multicellular (eg. Mushrooms,molds) cell wall of true fungi →compose of chitin
最common fungi → molds(mycelia (bread & fruit) → compose of long hyphae) 吸收nourishment by absorbing sol. of organic material from environment (eg. Soil , seawater)slime molds → 擁有characteristics of both fungi & amoebas

Protozoa
-unicellular
-move by pseudopods, flagella , cilia
吸收nutrients from absorb or ingest organic compound
*Euglena → photosynthetic, use light as source and carbon dioxide as chief source to produce sugars Amebae都係move by using pseudopods

Algae
好多shapes & sexually & asexual reproductive forms. -usually unicellular
-rich in freshwater, salt water, soil, association wif plants -photosynthesis for food production & growth
-no need organic compounds
-Produce oxygen & carbohydrates for other organisms(eg. Animal)

Viruses
-so small (diff. From the aboves)
-acellular (nt cellular)
-only one type of nucleic acid (DNA/RNA)
-st encase by envelope
-reproduce by using the cellular machinery of other organisms. -parasites of other forms of life (靠其他生命生存like 寄生蟲)

Multicellular Animal Parasites
-eukaryotes
-eg. helminths(蠕蟲)

Genetics info. In a cell = genome
Chomosomes contains DNA(genes)
Genes = segment of DNA

Genotype & Phenotype
G. = inheritable info. (可繼承的)
P. = 受G.影嚮而表現出來, eg. Blood, height, iq, color of eye

Ch. 10
Three domain: eukaryotes + prokaryotes (bacteria, archaea)-Each domain shares genes wif other domains eg. Thermotoga係從an archaeon演變的 -Kingdom → Phylum → class → order → family → Genus → species *Classification is base on similarity in nucleotide sequence in rRNAProkaryotes vs Virus:::-Virus cannot survive independently.-Virus 依賴host cell

Ch. 4
After dividing, Cocci → pairs = diplococci
→ chainlike = streptococci
→ groups of four = tetrads
→ groups of eight = sarcine
→ grapelike clusters = staphylococci

Bacilli → single = single bacillus
→ pairs = diplobacilli
→ chains = streptobacilli
→ oval, like cocci = coccobacilli
Spiral → curved = vibrios
→ helical shape,rigid = spirillum
→ helical shape, flexible = spirochete

External of cell wall
-Glycocalyx (gelatinous polysaccharide & / polypetide covering) → Capsule = the substance is organized & is firmly attached to the cell wall (*protect pathogens from phagocytosis & prevent desiccation) → Slime layer = .. unorganized & only loosely attacted. → Extracellular polysaccharide

-Flagella
→ rotate to push the cell
→ +ve taxis(movement of bacterium) moves towards an attractant, -ve taxis moves away from a repellent

-Axial Filaments
→ spiral cells tht move by spirochetes
→ similar to flagella, diff. : it wrap around the cell (包住)

-Fimbriae and pili
→ help cells adhere to surfaces
→ pili are involved in DNA transfer & twiching motility

Cell wall
-prevent bacterial cells from...
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