Topic: Quizzes on algae, virus, protozoa, bacteria, archaea, fungi
Each group looked for a video which is related to the topic. The video is posted in ED puzzle and quizzes are added to the video.
Sunday, 17 May 2015
6th Lecture: 14/5/15
Topic: Algae
Notes：
1) Algae distirbuted in aquatic and terresterial environment. There are 3 types of aquatic environment:
6) There are 7 divisions of algae and 5 from kingdom protista and 2 from kingdom plantae.
Reflection:
As I compare the algae notes from Dr. Sieo and Dr.Wan, both notes are informative. There are a lot of additional information that contain in either notes but not in another notes. I have learnt a lot about algae from both notes. One of the difficulty when study algae is to memorise the pigments contain in different types of algae. I feel interested in the practical importance of algae and other microorganisms because I don't want just study but at least to know how microorganisms contribute to us.
Notes：
1) Algae distirbuted in aquatic and terresterial environment. There are 3 types of aquatic environment:
- Planktonic- suspended in aqueous environemnt
- Benthic- attached and living in the bottom of water
- Neustonic- at water-atmosphere interface
2) Algae are photoautotrophic or chemoheterotrophic organisms.
3) Algae can reproduce sexually and asexually (fragmentation, spores and binary fission).
4) The process of the formation of gametes called gametogenesis. The female structure is called oogonia and eggs will produced. The male structure is called antheridia and sperms will produced. The fusion of eggs and sperms will form zygote.
5) There are two categories in sexual reproduction:
Two different types of gametes are produced. The male sperms is typically very small, highly motile, and is produced in very large numbers. The female eggs are much larger and non motile.3) Algae can reproduce sexually and asexually (fragmentation, spores and binary fission).
4) The process of the formation of gametes called gametogenesis. The female structure is called oogonia and eggs will produced. The male structure is called antheridia and sperms will produced. The fusion of eggs and sperms will form zygote.
5) There are two categories in sexual reproduction:
- Isogamy
- Heterogamy
6) There are 7 divisions of algae and 5 from kingdom protista and 2 from kingdom plantae.
- Chlorophyta (protista)
- unicellular or multicellular
- green
- contain chlorophyll a and chlorophyll b
- green
- contain chlorophyll a and chlorophyll b
- store glucose and energy in the form of starch
- contain carotenoid
- cell wall made up of cellulose
- can undergo sexual and asexual reproduction
- form different structure: unicellular, colonial, filamentous, membranous and goblet
- unicellular or multicellular
- cell wall contain microfibril and mucilaginous matrix which composed of agar, funori, porphysan and carrageenan. All these substances give flexible and slippery texture to rhodophyta.
- undergo sexual reproduction
- store glucose and energy in the form of floridean strach
- contain chlorophyll a and d, phycocyanin (blue) and phycoerythrin (red)
- chlorophyll a and c, xanthophylls, beta-carotene, violaxanthin
- multicellular
- cellulose or algin cell wall
- sexual reproduction
- store glucose and energy in the form of laminarin
a) Golden-brown algae
b) Yellow-green algae
c) Diatoms
- produce domic acid
- chlorophyll a and c
- unicellular
- peptin and silica cell wall
- sexual reprodution
- caratenoid fucoxanthin is the important pigment in chrysophyta
- Fucoxanthin is the dominant pigment in golden-brown algae
- store glucose and energy in the form of chrysolaminarin
- marine and fresh water algae
- brown
- 2 flagella in perpendicular opposite grooves
- some produce neurotoxins
- can cause red tides
- chlorophyll a and c
- cellulose cell wall, carotenoid and xantohophyll
- store starch
- free living endosymbionts
- unicellular flagellated
- chlorophyll a and b, carotene
- can spontaneous lost chlorophyll in dark - heterotrophic organisms
- no cell wall
- rigid plasma membrane - pellicle
- no sexual reproduction
- store glucose and energy in the form of paramylon
My own explorace:
1) Carotenoid usually perform two kind of functions in photosynthesis. They serve as accessory light harvesting pigments, extending the range of wavelengths over which light can drive photosynthesis, and they act to protect the chlorophyllous pigments from the harmful photodestructive reaction which occurs in the presence of oxygen.
2) Violaxanthin is a natural xanthophyll pigment with an orange color found in a variety of plants.
3) There are few importance of diatoms:
- food source for fish and marine animals
- dead atoms will sink to the bottom of ocean and from diatomaceous earth
- diatomaceous earth can used in detergents, abrasive polishes, paint, removers and also used to control insects and as the indicators of water quality.
4) To the insects, the diatomaceous earth is a lethal dust with microscopic sharp edges that cut through the insect’s protective covering, causing them to dry out, thus killing them when they are either dusted with the diatomaceous earth or applied in a wet spray form.
5) Algae suitable to be indicator of water quality because of their nutrient needs, rapid reproduction and short life cycle. They respond quickly both in species composition and densities to a wide range of water conditions due to changes in water chemistry.
- form different structure: unicellular, colonial, filamentous, membranous and goblet
- Rhodophyta ( belongs to kingdom plantae )
- unicellular or multicellular
- cell wall contain microfibril and mucilaginous matrix which composed of agar, funori, porphysan and carrageenan. All these substances give flexible and slippery texture to rhodophyta.
- undergo sexual reproduction
- store glucose and energy in the form of floridean strach
- contain chlorophyll a and d, phycocyanin (blue) and phycoerythrin (red)
- Phaeophyta ( belongs to kingdom plantae )
- chlorophyll a and c, xanthophylls, beta-carotene, violaxanthin
- multicellular
- cellulose or algin cell wall
- sexual reproduction
- store glucose and energy in the form of laminarin
- Chrysophyta
a) Golden-brown algae
b) Yellow-green algae
c) Diatoms
- produce domic acid
- chlorophyll a and c
- unicellular
- peptin and silica cell wall
- sexual reprodution
- caratenoid fucoxanthin is the important pigment in chrysophyta
- Fucoxanthin is the dominant pigment in golden-brown algae
- store glucose and energy in the form of chrysolaminarin
- Pyrrophyta
- marine and fresh water algae
- brown
- 2 flagella in perpendicular opposite grooves
- some produce neurotoxins
- can cause red tides
- chlorophyll a and c
- cellulose cell wall, carotenoid and xantohophyll
- store starch
- free living endosymbionts
- Euglenophyta
- unicellular flagellated
- chlorophyll a and b, carotene
- can spontaneous lost chlorophyll in dark - heterotrophic organisms
- no cell wall
- rigid plasma membrane - pellicle
- no sexual reproduction
- store glucose and energy in the form of paramylon
My own explorace:
1) Carotenoid usually perform two kind of functions in photosynthesis. They serve as accessory light harvesting pigments, extending the range of wavelengths over which light can drive photosynthesis, and they act to protect the chlorophyllous pigments from the harmful photodestructive reaction which occurs in the presence of oxygen.
2) Violaxanthin is a natural xanthophyll pigment with an orange color found in a variety of plants.
3) There are few importance of diatoms:
- food source for fish and marine animals
- dead atoms will sink to the bottom of ocean and from diatomaceous earth
- diatomaceous earth can used in detergents, abrasive polishes, paint, removers and also used to control insects and as the indicators of water quality.
4) To the insects, the diatomaceous earth is a lethal dust with microscopic sharp edges that cut through the insect’s protective covering, causing them to dry out, thus killing them when they are either dusted with the diatomaceous earth or applied in a wet spray form.
5) Algae suitable to be indicator of water quality because of their nutrient needs, rapid reproduction and short life cycle. They respond quickly both in species composition and densities to a wide range of water conditions due to changes in water chemistry.
Reflection:
As I compare the algae notes from Dr. Sieo and Dr.Wan, both notes are informative. There are a lot of additional information that contain in either notes but not in another notes. I have learnt a lot about algae from both notes. One of the difficulty when study algae is to memorise the pigments contain in different types of algae. I feel interested in the practical importance of algae and other microorganisms because I don't want just study but at least to know how microorganisms contribute to us.
Thursday, 14 May 2015
Fifth Lecture: 13/5/2015
Topic: Fungi
Notes:
1) The structure of fungi:
The body of fungus is called thallus. The main body of most fungi is made up of fine, branching, usually colourless threads called hyphae. Each fungus will have vast numbers of these hyphae, all intertwining to make up a tangled web called the mycelium.
The mycelium is generally too fine to be seen by the naked eye, except where the hyphae are very closely packed together. The picture on the left was taken through a microscope.
2) There are two types of hyphae: septate hyphae and coenocytic hyphae. Septate hyphae have divider between cells and there have opening pores between the cells which allow the flow of nutrient and cytoplasm between the cells. Coenocytic hyphae form one cell with many nuclei.
3)
Fungi undergoes asexual and sexual reproduction. There are three types of asexual reproduction: Bud formation, fragmentation and sporulation.
- Bud formation
- Mitosis process
- Development of a ring of chitin around the point of budding
- enzymatic activity extrude the cell wall and cell content are forced into the progeny cell.
- At the end of mitosis, a cell plate forms and the new bud detaches.
- Fragmentation
- any mycelium that is fragmentated can grow into a new colony.
- common sub-culturing method for fungi ( hyphal fragment technique)
- cork bore taken from a colonized donor plate. Cut mycelial tips do not generate but branches can form some distance from the damage point.
- Sporulation
- the production of spores on a phase called mitosporic, or anamorphic phase
- Arthrospores are formed through segemntation and condensation of hyphae.
- Chlamydospores are spores that surrounded by thick cell wall.
- Sporangiospores are the development of spores within a sac at hyphal tip.
- Conidiospores are spores that are not enclosed in sac produced at the tips or sides of hypha.
- Blastospores are spores produced from mother cell by budding.
4) For sexual reproduction, the different mating types need to fuse to form diploid first, but once fused the nuclei undergo mitosis. The event are followed by the formation of spores, which in most cases are resting spores that can withstand adverse conditions.
5) Slime molds once placed in kingdom Fungi but now placed in kingdom Protista. slime mold resemble fungi in appearance and life style but different in cellular organisms, reproduction and life cycle. Four different phyla of slime molds are:
- Myxomycota
These slime molds are designated as myxamoeba because their morphology are similar to amoeba. They are multinucleated, lack of cell wall, and phagocytosized dead material. The life cycle of myxocetes will start with the production of spores, then the release of myxamoebae. If free water is available, myxocetes will differentiate into swarm cells. Then sexual reproduction will occur where the swarm cells will normally act as gametes. Once compatible mating strains have come into contact with one another, syngamy will occur to form the zygote. The zygote then undergo numerous mitotic divisions to form the large, multinucleate plasmodium. This class is commonly referred to as the acellular slime molds because the plasmodium stage of the lif ecycle is not composed of many cells. During favorable conditions, the plasmodium will migrate and feed for a period of time before being converted to numerous sporangia.
- Acrasiomycota
Cellular slime molds closely resemble amoebas in structure. These molds live independently until food runs out. A starving amoeba secretes the hormone cyclic AMP into the environment. Other amoebas detect the cyclic AMP as a food source and aggregate from great distances to follow the concentration gradient to the dying amoeba. The amoebas then attach to one another and become what seems to be a functioning multicellular organism. The moving slug finds a suitable habitat before forming itself into a diploid fruiting body called a sorocarp, which releases encysted amoebas or diploid macrocysts. The released amoebas live independently until food resources are depleted, then the cycle is repeated.
- Oomycota
Oomycetes are water mold and oogamous where is produces large female gametes and small male gametes. Oomycetes were once recognised as fingi due to branched filaments and decaying dead matter. However, the cell wall of chitin is not composed of chitin, but with cellulose. Some water molds are parasitic because they live on fish or plant root which damage the plant root. As in humans as well as plants and other animals, sexual reproduction in the Oomycota involves specialized reproductive structures where meiosis can occur and gametes formed. These structures are called antheridia and oogonia in the Oomycota. The male and female fuse to form zygote.
6) Deuteromycota is known as fungi imperfecti because they are fungi which do not fit into the commonly established taxonomic classifications of fungi that are based on biological species concepts or morphological characteristics of sexual structures because their sexual form of reproduction has never been observed. Their cell wall is made up of chintin and glucan. They live in terrestrial, freshwater and marine. they are saprophytes and parasites of plants.
Activity: Presentation from group Fungi and group Algae.
My own explorace:
1) Zoonosis is the disease that directly transmitted from animal to human.
2) Potato Dextrose Agar contains dextrose as a carbohydrate source, and potato infusion to supply other necessary growth requirements. Potato infusion provides a nutrient base for luxuriant growth of most fungi.
3) The lactophenol cotton blue (LPCB) wet mount preparation is the most widely used method of staining and observing fungi and is simple to prepare.
4) Mycosis is a fungal infection of animal and human. Mycosis often misdiagnosed as TB because of their clinical and radiological characteristics are almost the same.
5) Endophytes are bacteria or fungi that live within a plant for at least part of its life without causing apparent disease.
6) Fungal allergens are generally proteins, and are often enzymes released from the fungal spore during germination, although some may also be proteins located on the surface of spores.
7) Most secondary metabolites are produced after fungi have completed its initial growth phase. Therefore secondary metabolites normally produced at the end of log phase. Some secondary metabolites produced by fungi are harmful but some are beneficial. The examples of secondary metabolites are penicillin, alfatoxin and gibberellin.
8) Normal fungi can just grow in petri dish while lower taxonomic microbes must grow in broth.
Reflection:
I don't really like fungi if compared to other microorganisms because I always confused with the life cycle of fungi. Sometimes I thought I understand the life cycle of fungi, but I can't explained to others because I know I am not really understand about it. The structure of fungi sometimes also make me confused. I can't imagine how thallus, hyphae and mycelium look like so I tried to search the image of thallus, hyphae and mycelium in the internet but I really wish to see the real thallus, hyphae and mycelium.
My own explorace:
1) Zoonosis is the disease that directly transmitted from animal to human.
2) Potato Dextrose Agar contains dextrose as a carbohydrate source, and potato infusion to supply other necessary growth requirements. Potato infusion provides a nutrient base for luxuriant growth of most fungi.
3) The lactophenol cotton blue (LPCB) wet mount preparation is the most widely used method of staining and observing fungi and is simple to prepare.
4) Mycosis is a fungal infection of animal and human. Mycosis often misdiagnosed as TB because of their clinical and radiological characteristics are almost the same.
5) Endophytes are bacteria or fungi that live within a plant for at least part of its life without causing apparent disease.
6) Fungal allergens are generally proteins, and are often enzymes released from the fungal spore during germination, although some may also be proteins located on the surface of spores.
7) Most secondary metabolites are produced after fungi have completed its initial growth phase. Therefore secondary metabolites normally produced at the end of log phase. Some secondary metabolites produced by fungi are harmful but some are beneficial. The examples of secondary metabolites are penicillin, alfatoxin and gibberellin.
8) Normal fungi can just grow in petri dish while lower taxonomic microbes must grow in broth.
Reflection:
I don't really like fungi if compared to other microorganisms because I always confused with the life cycle of fungi. Sometimes I thought I understand the life cycle of fungi, but I can't explained to others because I know I am not really understand about it. The structure of fungi sometimes also make me confused. I can't imagine how thallus, hyphae and mycelium look like so I tried to search the image of thallus, hyphae and mycelium in the internet but I really wish to see the real thallus, hyphae and mycelium.
Tuesday, 12 May 2015
Fourth Lecture: 8/5/15
Topic: Quizzes on the topic Bacteria
Dr. Wan, I went to Baksis Mega project on Friday. I didn't do the quizzes but I will update from May Ling. ^^
Thrid Lecture: 6/5/2015
Topic: Bacteria ( part 2 )
Bacteria
Notes:
1) Anoxygenic bacteria undergo photosynthesis in anaerobic condition. They have gram negative cell wall and oxygen is not the product of photosynthesis. They have bacteriochlorophyll and they are non pathogenic.
2) Oxygenic bacteria undergo photosynthesis in aerobic condition. They have gram negatice cell wall and oxygen is released during photosynthesis. Water as electron donor and they have chlorophyll. They are non pathogenic and also called cyanobacteria.
3) To differentiate Chromatium sp. , Chlorobium sp. and Rhodospirillum sp. , we need to refer to their colour of granules and pigments. Chromatium contain purple sulfur, Chlorobium contain green sulfur while Rhodospirillum contain purple nonsulfur. Some of the cyanobacteria have trichome and heterocysts.
4) There are 6 groups of gram positive bacteria with cell walls:
a) Gram positive cocci
-Streptococcus sp. and Staphylococcus sp.
- Use metabolic test to differentiate Streptococcus and Staphylococcus.
- Streptococci are catalase postitive (form bubbles) and Staphylococcus are catalase negative.(do not form bubbles)
b) Endospore-forming Gram positive rods and cocci
- Bacillus ( aerobes or facultative anaerobes ) and Clostridium ( obligate anaerobes )
- Example: Bacillus anthracis. Clostridium botulinum, Clostridium tetani, Clostridium perfringens
c) Regular non-spore forming gram positive rods
- rod shape
- Example: Lactobacillus (friendly bacteria)
- Homofermentative is the characteristics of Lactobacillus where they only produce lactic acid through Embden-Meyerhoff pathway.
- Heterofermentative is the chatacteristics pf Lactobacillus where they produce lactic acid, ethanol and carbon dioxide through Pentose Phosphate pathway.
d) Irregular nonsporing gram positive rods
- club-shaped rod with side by side alignment of cells
- Snapping binary fission
- Example: Corynebacterium diphtheriae
e) Mycobacteria
-use acid-fast stain
-slightly curved to straight rods
-Slow grower
- time needed to form cell wall contaning mycolic acid
- growth stimulated by lipid and fatty acids
- Glycerol-whole egg medium
-Example: Mycobacterium tuberculosis
f) Actinomycetes
- form mycelium but prokaryotes
- soil inhabitant
-produce antibiotic. For example: chloramphenicol, erythromycin, tetracycline
different actinomycetes have different composition and structure of cell wall, morphology and colour of mycelia and sporangia.
- they can recycle nutrient, degrade cellulose, lignin, chitin, latex, aromatic chemicals and keratin.
- Aerial filaments bearing reproductive spores which is known as conidia. Accumulation of conidia form the fluffy morphology.
5) Bacteria lacking cell wall are bacteria without regular cell wall or without cell wall. They are known as pleomorphic. the example of this bacteria is mycoplasma. They have strong plasms membrane which made up of sterols and lipoglycan. They form colonies with fried-egg appearance and require growth factors such as vitamin, amino acids and nucleotides.
Activities: The presentation from group Archae and the working of SCL from each group.
My Own Explorace:
1) Catalase is an enzyme used by bacteria to induce the reaction of reduction of hydrogen peroxide into water and oxygen.
2) Trichome is a chain of vegetative cells in cyanobacteria.
3) Heterocysts are specialized, pale-yellow,thick-walled cells with disputed function nitrogen-fixing formed during nitrogen starvation by some filamentous cyanobacteria.
4) The pictures of trichome and heterocysts:
5) Corynebacterium diphtheriae is the pathogenic bacterium that causes diphtheria. Diphtheria often come on fairly gradually beginning with a sore throat and fever. This can block the airway and create a barking cough as in croup. The neck may swell in part due to large lymph nodes. A form of diphtheria that involves the skin, eyes, or genitals also exists.
Bacteria
Notes:
1) Anoxygenic bacteria undergo photosynthesis in anaerobic condition. They have gram negative cell wall and oxygen is not the product of photosynthesis. They have bacteriochlorophyll and they are non pathogenic.
2) Oxygenic bacteria undergo photosynthesis in aerobic condition. They have gram negatice cell wall and oxygen is released during photosynthesis. Water as electron donor and they have chlorophyll. They are non pathogenic and also called cyanobacteria.
3) To differentiate Chromatium sp. , Chlorobium sp. and Rhodospirillum sp. , we need to refer to their colour of granules and pigments. Chromatium contain purple sulfur, Chlorobium contain green sulfur while Rhodospirillum contain purple nonsulfur. Some of the cyanobacteria have trichome and heterocysts.
4) There are 6 groups of gram positive bacteria with cell walls:
a) Gram positive cocci
-Streptococcus sp. and Staphylococcus sp.
- Use metabolic test to differentiate Streptococcus and Staphylococcus.
- Streptococci are catalase postitive (form bubbles) and Staphylococcus are catalase negative.(do not form bubbles)
b) Endospore-forming Gram positive rods and cocci
- Bacillus ( aerobes or facultative anaerobes ) and Clostridium ( obligate anaerobes )
- Example: Bacillus anthracis. Clostridium botulinum, Clostridium tetani, Clostridium perfringens
c) Regular non-spore forming gram positive rods
- rod shape
- Example: Lactobacillus (friendly bacteria)
- Homofermentative is the characteristics of Lactobacillus where they only produce lactic acid through Embden-Meyerhoff pathway.
- Heterofermentative is the chatacteristics pf Lactobacillus where they produce lactic acid, ethanol and carbon dioxide through Pentose Phosphate pathway.
d) Irregular nonsporing gram positive rods
- club-shaped rod with side by side alignment of cells
- Snapping binary fission
- Example: Corynebacterium diphtheriae
e) Mycobacteria
-use acid-fast stain
-slightly curved to straight rods
-Slow grower
- time needed to form cell wall contaning mycolic acid
- growth stimulated by lipid and fatty acids
- Glycerol-whole egg medium
-Example: Mycobacterium tuberculosis
f) Actinomycetes
- form mycelium but prokaryotes
- soil inhabitant
-produce antibiotic. For example: chloramphenicol, erythromycin, tetracycline
different actinomycetes have different composition and structure of cell wall, morphology and colour of mycelia and sporangia.
- they can recycle nutrient, degrade cellulose, lignin, chitin, latex, aromatic chemicals and keratin.
- Aerial filaments bearing reproductive spores which is known as conidia. Accumulation of conidia form the fluffy morphology.
5) Bacteria lacking cell wall are bacteria without regular cell wall or without cell wall. They are known as pleomorphic. the example of this bacteria is mycoplasma. They have strong plasms membrane which made up of sterols and lipoglycan. They form colonies with fried-egg appearance and require growth factors such as vitamin, amino acids and nucleotides.
Activities: The presentation from group Archae and the working of SCL from each group.
My Own Explorace:
1) Catalase is an enzyme used by bacteria to induce the reaction of reduction of hydrogen peroxide into water and oxygen.
2) Trichome is a chain of vegetative cells in cyanobacteria.
3) Heterocysts are specialized, pale-yellow,thick-walled cells with disputed function nitrogen-fixing formed during nitrogen starvation by some filamentous cyanobacteria.
4) The pictures of trichome and heterocysts:
5) Corynebacterium diphtheriae is the pathogenic bacterium that causes diphtheria. Diphtheria often come on fairly gradually beginning with a sore throat and fever. This can block the airway and create a barking cough as in croup. The neck may swell in part due to large lymph nodes. A form of diphtheria that involves the skin, eyes, or genitals also exists.
6) Serpertine arrangement of Mycobacterium tuberculosis:
7) Glycerol whole-egg medium provide fatty acids and protein neccessary for the metabolism of mycobacteria. The coagulation of the egg albumin during sterilization gives a solid medium for inoculation purposes
8) Vibrio cholerae can produce endospores but endospore will germinate after few hours the endospore formed. Therefore, Vibrio cholerae is not dorminant endospore forming bacteria.
9) Three in 10 Americans carry staph bacteria in their noses, where the germs live benignly unless they are allowed to enter the body through an open wound like a surgical incision. If one of these patients touches his or her nose and then the surgical site, the patient will get infected with Staphylococcus aureus infection. Doctors swab patients’ noses before surgery to test for Staphylococcus aureus bacteria. If the patient has Staphylococcus aureus bacteria naturally living in his or her nose, apply an antibiotic nose ointment in the days before surgery. Up to 85 percent of staph infections are caused by a patient’s own bacteria, meaning that we’re actually infecting ourselves.
10) Escherichia coli possess the ability to transfer DNA via bacterial conjugation, transduction or transformation, which allows genetic material to spread horizontally through an existing population. This process led to the spread of toxin from E. coli O157:H7 to other E.coli .
11) There are five basic mechanisms of antibiotic action against bacterial cells:
- Inhibition of Cell Wall Synthesis (most common mechanism)
- Inhibition of Protein Synthesis (Translation) (second largest class)
- Alteration of Cell Membranes
- Inhibition of Nucleic Acid Synthesis
- Antimetabolite Activity
12) Cutaneous anthrax is the most common form of anthrax infection, and it is also considered to be the least dangerous. When anthrax spores get into the skin, usually through a cut or scrape, a person can develop cutaneous anthrax.
11) There are five basic mechanisms of antibiotic action against bacterial cells:
- Inhibition of Cell Wall Synthesis (most common mechanism)
- Inhibition of Protein Synthesis (Translation) (second largest class)
- Alteration of Cell Membranes
- Inhibition of Nucleic Acid Synthesis
- Antimetabolite Activity
12) Cutaneous anthrax is the most common form of anthrax infection, and it is also considered to be the least dangerous. When anthrax spores get into the skin, usually through a cut or scrape, a person can develop cutaneous anthrax.
Reflection:
This is my first time to hear that antibiotic can be apply on skin and nostrils to kill the bacteria. I guess the endospore of Vibrio cholerae will germinate rapidly is because the survival condition of Vibrio cholerae is close and same with our normal condition. Therefore, when Vibrio cholerae reach its favoured environmental condition, it will straight away germinate. I learnt the use of the number in a journal. The number in the journal refer to the number of reference below the journal. This is to let the reader to check the content inside the journal from the reference given.
Sunday, 26 April 2015
First lecture and second lecture : 22/4/2015 and 24/4/2015
Dr. Wan, for the last week lesson I will combine them into one post.
Topic: Bacteria
Notes:
1) We can use different traits to classify bacteria: cell type, morphology, metabolism, reproduction, phage typing, nucleic acid profile and antibiotic resistance profile.
2) Prokaryotes are divided into 4 category.
a) Category 1: Gram -ve bacteria with cell wall
Gram -ve bacteria have thin layer of peptidoglycan in between cytoplasmic membrane and outer membrane of cell wall.
3) Gram -ve bacteria with cell walls can be divided into 2 groups based on reproduction and light. One of the groups is nonphototrophic. Nonphototrophic bacteria contain 14 subgroups and 6 of the subgroups are pathogens.
a) Enteric groups
- facultative anaerobic short rods
- E.coli O157:H7 causing uninary tract infection
-
b) Campylobacter and Helicobacter
- Aerobic, microaerophilic
- motile
- helical/vibriod bacteria
- Campylobacter jejuni causing diarrhea
- Helicobacter pylori causing ulcer
c) Spirochetes
- slender and long with flexible and helical shape
- corkscrew movement
- They have endoflagella that coil around the cell for cork screw movement.
- causing syphilis and lyme disease
d) Chlamydias
- Obligately intracellular parasites
- resemble virus- intracellular parasites and size
- they are different from virus because they have both DNA and RNA, plasma membrane, metabolic pathways, reproduction by binary fission.
- causing eye/genitourinary tract infection.
e) Pseudomonas, Azobacter and Rhibozium
- nonpathogenic
- Pseudomonas sp. degrade complec organic molecule in soil
- Azobacter and Rhibozium do nitrogen fixation in soil
Activity: Do mind map using padlet and each group need to present one of the kingdom in front of the class.
My own Explorace:
1) Facultative anaerobe is an microorganism that makes ATP by aaerobic respiration if oxygen is present, but is capable of switching to fermentation or anaerobic respiration if oxygen is absent.
2) Microaerophile is a microorganism that requires oxygen to survive, but requires environments containing lower levels of oxygen that are present in atmosphere.
3) Treponema pallidum cause syphilis and Borrelia burgdorferi cause lyme disease. Lyme disease is transmitted to humans by the bite of infected ticks of the Ixodes genus.
4) Chlamydia trachomatis cause eye infection. Chlamydia infections are the most common bacterial sexually transmitted diseases in humans and are the leading cause of infections blindness worldwide.
Reflection:
E-port folio again. I thaught I will never touch this blog anymore. My feeling to this blog is complicated. It took over few hours of my happy weekend to complete e-port folio. But, I admit I can revised again what Dr taught and take initiative to look for the things that I don't understand. There are few things that we have learnt in semester 1 but I already forgot. For example, I have forgot the name of bacteria that caused syphilis. Dr.Wan introduced new apps, pedlet to us in class. Although Dr have mentioned pedlet before, but this is my first time to use it. I think it is very convenient for group mindmap.
Friday, 10 April 2015
Semester 2 - Classification, identification, nomanclature and immunology
Dr. Sieo have taught two big topic in this seven weeks - Classification, identification, nomenclature and immunology.
These two links are the mindmap that I did for classification, identification, nomenclature and immunology:
https://www.goconqr.com/en-US/p/2303520
https://www.goconqr.com/en-US/p/1587060
These are the summary for the Immunology topic:
The examples of primary lymphoid organs are bone marrow and thymus. The examples of secondary lymphoid organs are adenoid, tonsils, lymph nodes and spleen.
Mononuclear leucocyte: T cell, B cell, NK cell, monocyte.
Polymorphonuclear leucocyte: neutrophil, eosinophil and basophil.
B cells are mast cells that mature in bone marrow. The function of B cell is to interact antigen, produce antibody and immune memory. T cells are mast cells that mature in Thymus. The function of T cells is to recognise processed antigen presented in MHC molecule on antigen-presenting cells.
CD4 T cells are the T cells that present CD4 glycoprotein on their cell surface while CD8 T cells are T cells that present CD8 glycoprotein on their cell surface. T helper 1 cells and T helper 2 cells belong to CD4 T cells and T cytotoxic cells belong to CD8 T cells.
Antigen are the molecules that trigger specific immune response and react with products of response. There are four feature of good antigens:
a) high molecular weight
b) complexity
c) solubility
d) foreigness
Recognition of antigens:
a) B cells - whole antigen
b) Antibody - Antigen's epitope
c) T-cell receptor - processed antigen
There are 5 types of antibodies : IgM, IgG, IgD, IgA, IgE.
Antibody consist of 4 polypeptide chain where 2 light chain and 2 heavy chain. Fab will be the site that bind to the pathogen while Fc will be the part that bind to macrophage.
** If 2 different classes of antibody react with one antigenic determinant, the constant heavy chain will be different but the heavy and light chain will be the same.
**If 2 same classes of antibody react with two different antigenic determinant, the constant havy chain will be the same but the heavy and light chain will be different.
There are two types of immune response : non-specific immune response and specific immune response.
a) non-specific immune response are internal innate imununity and external innate immunity.
External innate immunity include skin, mucuous membrane, normal microbiota. Periodic drying of skin and slightly acidic pH of skin create unfavourable environment for pathogen to survive. Globet cells secrete mucus to trap the bacteria or pathogen to expel out from body. Normal microbiota compete nutrients with pathogen and secrete antimicrobial substances to inhibit the growth of pathogen.
Internal innate immunity include fever, inflammation and phagocytosis. Fever is to create unfavourable temperature in the body to trigger microbiostasis. High amount of pathogen will produce high amount of pyrogen. the pyrogen will send to hypothalamus and produce prostaglandins which will reset the hypothalamic thermostat. Inflammation is due to the phagocytosis not effective. Histamine released and causes vasodilation. Vasodilation will will deliver more blood to infection site and the macrophage will more permeable move from blood vessel into damaged tissue site. Phagocytosis is the engulfment of pathogen by macrophage or neutrophils.
b) Specific immune response are humoral immunity and cell-mediated immunity. Humoral immunity is an immunity mediated by macromolecules that found in serum.
How does antibody gives protection?
a) Neutralisation
b) Agglutination
c) Oponisation
d) Activation of complement
e) ADCC ( antibody-dependent cell mediated toxicity)
** Antibody do not kill the pathogen but serach the pathogen by others.
How to determine the latent period?
1) Dosage of antigen
2) Adjuvants
3) Chemical and physical nature of antigens
What are the differences between primary antibody response and secondary antibody response?
Secondary antibody response will have short latent period, higher titer, longer persistence of antibody and more rapid increase in antibody titer if compared with primary antibody response.
Cell-mediated immunity is an immunity response that does not involve antibody but rather involve the activation of macrophage, Tc cell and the release of various cytokine in response to antigen.
There are two types of CD8 T cells killing mechanisms:
a) granules exocytosis
When TcR bind to antigen on class 1 MHC, granule is released to activate apoptosis. Granules contain perforin and granzymes.
b) Fas pathway
When TcR bind to antigen on class 1 MHC, granules are release and triggers expression fas-ligand on Tc cell and the Fas on target cell cross-linked with Fas-ligand.
Delayed-type hypersensitivity (DTH)
- against pathogens living inside macrophages themselves
a) Dendritic cells will pick up the antigens that presented on class 2 MHC and move to secondary lymphoid organ.
b) Dendritic cells will process the antigen and preseneted it on the class 2 MHC CD4 T cell in the secondary lymphoid organ will then activated by the antigen.
c) CD4 T cell will then proliferate, differentiate to T helper 1 cell. T helper 1 cell will then migrate back to the site of infection and secrete cytokines to recruit more monocyte or macrophages to phagocyte the pathogen on the infection site.
Reflection:
Obviously, the topics for semester 2 are harder than the topic in semester 1. Luckily we have Dr. Sieo as our lecturer and taught us in very details way so that we can fully understand these two topics. I like the topic of immunology more if compared with classification and identification. The identification method are all practical but we only understand the basic concept of the methods. That's why I feel less interest in this topic. The topic of immunology is interesting because I would like to know how the pathogen gain access to our body and cause infection. Antibody is important to fight with the pathogen and the process of producing antibody is complicated and it take a long time to produce.
These two links are the mindmap that I did for classification, identification, nomenclature and immunology:
https://www.goconqr.com/en-US/p/2303520
https://www.goconqr.com/en-US/p/1587060
These are the summary for the Immunology topic:
The examples of primary lymphoid organs are bone marrow and thymus. The examples of secondary lymphoid organs are adenoid, tonsils, lymph nodes and spleen.
Mononuclear leucocyte: T cell, B cell, NK cell, monocyte.
Polymorphonuclear leucocyte: neutrophil, eosinophil and basophil.
B cells are mast cells that mature in bone marrow. The function of B cell is to interact antigen, produce antibody and immune memory. T cells are mast cells that mature in Thymus. The function of T cells is to recognise processed antigen presented in MHC molecule on antigen-presenting cells.
CD4 T cells are the T cells that present CD4 glycoprotein on their cell surface while CD8 T cells are T cells that present CD8 glycoprotein on their cell surface. T helper 1 cells and T helper 2 cells belong to CD4 T cells and T cytotoxic cells belong to CD8 T cells.
Antigen are the molecules that trigger specific immune response and react with products of response. There are four feature of good antigens:
a) high molecular weight
b) complexity
c) solubility
d) foreigness
Recognition of antigens:
a) B cells - whole antigen
b) Antibody - Antigen's epitope
c) T-cell receptor - processed antigen
There are 5 types of antibodies : IgM, IgG, IgD, IgA, IgE.
Antibody consist of 4 polypeptide chain where 2 light chain and 2 heavy chain. Fab will be the site that bind to the pathogen while Fc will be the part that bind to macrophage.
** If 2 different classes of antibody react with one antigenic determinant, the constant heavy chain will be different but the heavy and light chain will be the same.
**If 2 same classes of antibody react with two different antigenic determinant, the constant havy chain will be the same but the heavy and light chain will be different.
There are two types of immune response : non-specific immune response and specific immune response.
a) non-specific immune response are internal innate imununity and external innate immunity.
External innate immunity include skin, mucuous membrane, normal microbiota. Periodic drying of skin and slightly acidic pH of skin create unfavourable environment for pathogen to survive. Globet cells secrete mucus to trap the bacteria or pathogen to expel out from body. Normal microbiota compete nutrients with pathogen and secrete antimicrobial substances to inhibit the growth of pathogen.
Internal innate immunity include fever, inflammation and phagocytosis. Fever is to create unfavourable temperature in the body to trigger microbiostasis. High amount of pathogen will produce high amount of pyrogen. the pyrogen will send to hypothalamus and produce prostaglandins which will reset the hypothalamic thermostat. Inflammation is due to the phagocytosis not effective. Histamine released and causes vasodilation. Vasodilation will will deliver more blood to infection site and the macrophage will more permeable move from blood vessel into damaged tissue site. Phagocytosis is the engulfment of pathogen by macrophage or neutrophils.
b) Specific immune response are humoral immunity and cell-mediated immunity. Humoral immunity is an immunity mediated by macromolecules that found in serum.
How does antibody gives protection?
a) Neutralisation
b) Agglutination
c) Oponisation
d) Activation of complement
e) ADCC ( antibody-dependent cell mediated toxicity)
** Antibody do not kill the pathogen but serach the pathogen by others.
How to determine the latent period?
1) Dosage of antigen
2) Adjuvants
3) Chemical and physical nature of antigens
What are the differences between primary antibody response and secondary antibody response?
Secondary antibody response will have short latent period, higher titer, longer persistence of antibody and more rapid increase in antibody titer if compared with primary antibody response.
Cell-mediated immunity is an immunity response that does not involve antibody but rather involve the activation of macrophage, Tc cell and the release of various cytokine in response to antigen.
There are two types of CD8 T cells killing mechanisms:
a) granules exocytosis
When TcR bind to antigen on class 1 MHC, granule is released to activate apoptosis. Granules contain perforin and granzymes.
b) Fas pathway
When TcR bind to antigen on class 1 MHC, granules are release and triggers expression fas-ligand on Tc cell and the Fas on target cell cross-linked with Fas-ligand.
Delayed-type hypersensitivity (DTH)
- against pathogens living inside macrophages themselves
a) Dendritic cells will pick up the antigens that presented on class 2 MHC and move to secondary lymphoid organ.
b) Dendritic cells will process the antigen and preseneted it on the class 2 MHC CD4 T cell in the secondary lymphoid organ will then activated by the antigen.
c) CD4 T cell will then proliferate, differentiate to T helper 1 cell. T helper 1 cell will then migrate back to the site of infection and secrete cytokines to recruit more monocyte or macrophages to phagocyte the pathogen on the infection site.
Reflection:
Obviously, the topics for semester 2 are harder than the topic in semester 1. Luckily we have Dr. Sieo as our lecturer and taught us in very details way so that we can fully understand these two topics. I like the topic of immunology more if compared with classification and identification. The identification method are all practical but we only understand the basic concept of the methods. That's why I feel less interest in this topic. The topic of immunology is interesting because I would like to know how the pathogen gain access to our body and cause infection. Antibody is important to fight with the pathogen and the process of producing antibody is complicated and it take a long time to produce.
Subscribe to:
Posts (Atom)