Bacteria come in a variety of shapes and sizes. They can be spherical (cocci), rod-shaped (bacilli), spiral (spirilla), or slender and flexible (spirochetes). Some bacteria arrange in pairs (diplococci), chains (streptococci), or clusters (staphylococci). Bacterial cells have a cell wall, cytoplasm, ribosomes, and often flagella, pili, or a capsule. The cell wall provides shape and some protection, while the plasma membrane controls what enters and exits the cell. Bacteria can form tough endospores to survive unfavorable conditions. Understanding bacterial morphology is important for classification and identification.
Bacterial and Fungal CULTURE PRESERVATION.
SERIAL TRANSFER
PRESERVATION IN D/W
PRESERVATION UNDER OIL
LYOPHILIZATION
STORAGE OVER SILICA GEL
PRESERVATION ON PAPER
PRESERVATION ON BEADS
PRESERVATION ON SOIL
LIQUID DRYINNG.
CRYOPRESERVATION.
FROZEN AGAR PLUGS
PRESERVATION IN LIQ NITROGEN
2-STAGE FREEZING PROCESS
Capsule is an layer around the bacteria cell which gives bacteria the protection and pathogenicity. Staining such an layer is difficult with the normal stains so it is necessary to stain the background and the cell itself which makes the capsule appear colourless.
Bacterial and Fungal CULTURE PRESERVATION.
SERIAL TRANSFER
PRESERVATION IN D/W
PRESERVATION UNDER OIL
LYOPHILIZATION
STORAGE OVER SILICA GEL
PRESERVATION ON PAPER
PRESERVATION ON BEADS
PRESERVATION ON SOIL
LIQUID DRYINNG.
CRYOPRESERVATION.
FROZEN AGAR PLUGS
PRESERVATION IN LIQ NITROGEN
2-STAGE FREEZING PROCESS
Capsule is an layer around the bacteria cell which gives bacteria the protection and pathogenicity. Staining such an layer is difficult with the normal stains so it is necessary to stain the background and the cell itself which makes the capsule appear colourless.
COLLECTION AND TRANSPORTATION OF CLINICAL SAMPLESNCRIMS, Meerut
Principles of Sample Collection:
Aseptic precautions to minimize chances of
contamination.
Appropriate anatomic sites
Adequate volume
Adequate no. of samples
Appropriate time
Appropriate container with proper labelling
Before initiation of anti-microbials
Adequate information in request form
pseudomonas aeruginosa is one of the leading cause of hospital-associated infection. mainly Pseudomonas is a multi drug resistant bacteria.
they are oxidase positive, non fermenters, strictly aerobic bacteria.
they are pigment producing, pigment can be appreciated on nutrient agar.
COLLECTION AND TRANSPORTATION OF CLINICAL SAMPLESNCRIMS, Meerut
Principles of Sample Collection:
Aseptic precautions to minimize chances of
contamination.
Appropriate anatomic sites
Adequate volume
Adequate no. of samples
Appropriate time
Appropriate container with proper labelling
Before initiation of anti-microbials
Adequate information in request form
pseudomonas aeruginosa is one of the leading cause of hospital-associated infection. mainly Pseudomonas is a multi drug resistant bacteria.
they are oxidase positive, non fermenters, strictly aerobic bacteria.
they are pigment producing, pigment can be appreciated on nutrient agar.
What is bacteria?(Structures Present in Bacteria And their Functions | Prokar...sehriqayyum
Explains what bacteria is and where it exists.
A key feature of nearly all prokaryotic cells is the cell wall, which maintains cell shape, protects the cell, and prevents it from bursting in a hypotonic environment.
The cell walls of prokaryotes differ in structure from those of eukaryotes. In eukaryotes that have cell walls, such as plants and fungi, the walls are usually made of cellulose or chitin. In contrast, most bacterial cell walls contain peptidoglycan, a polymer composed of modified sugars cross-linked by short polypeptides.
Using a technique called the Gram stain, developed by the 19th-century Danish physician Hans Christian Gram, scientists can categorize many bacterial species according to differences in cell wall composition.
Gram-positive bacteria have simpler walls with a relatively large amount of peptidoglycan. Gram-negative bacteria have less peptidoglycan
and are structurally more complex, with an outer membrane
that contains lipopolysaccharides (carbohydrates bonded
to lipids).
LEARN ABOUT:
- Bacteria
- The number of viruses on earth is staggering
- Pathogenic yeasts
- Helminths
- Harnessing bacteria
- Microbes on the tree of life
- Living and working together
- Archaea
- Protozoa
LEARN ABOUT:
- Bacteria
- The number of viruses on earth is staggering
- Pathogenic yeasts
- Helminths
- Harnessing bacteria
- Microbes on the tree of life
- Living and working together
- Archaea
- Protozoa
The bacterial flagellum has three main parts (the motor, hook, and filament) that are themselves composed of 42 different kinds of proteins.The cells of prokaryotes are simpler than those of eukaryotes
in both their internal structure and the physical arrangement
of their DNA. The genome of a prokaryote is structurally different from
a eukaryotic genome and in most cases has considerably less DNA. Prokaryotes generally have circular chromosomes, whereas eukaryotes have linear chromosomes.
Bacteria are unicellular, procaryotic microorganisms which have diverse shape size and structures. Bacteria are found almost everywhere on Earth. Even the human body is full of bacteria, and in fact is estimated to contain more bacterial cells than human cells. Most bacteria in the body are harmless, and some are even helpful. A relatively small number of species cause disease.
Bacterial Morphology and Atomy.pptx microbiologyosmanolow
Microbiology is the study of the biology of microscopic organisms - viruses, bacteria, algae, fungi, slime molds, and protozoa. The methods used to study and manipulate these minute and mostly unicellular organisms differ from those used in most other biological investigations
Microbiology is the study of the biology of microscopic organisms - viruses, bacteria, algae, fungi, slime molds, and protozoa. The methods used to study and manipulate these minute and mostly unicellular organisms differ from those used in most other biological investigations
Ultrastructure and characterstic features of bacteria.Archana Shaw
Ultrastructure and characterstic features of bacteria: BACTERIA AS A MODEL ORGANISM
THIS WAS MY PRESENTATION TOPIC IN CLASS. THOUGHT OF SHARING IT AND HOPE IT HELPS.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
HOT NEW PRODUCT! BIG SALES FAST SHIPPING NOW FROM CHINA!! EU KU DB BK substit...GL Anaacs
Contact us if you are interested:
Email / Skype : kefaya1771@gmail.com
Threema: PXHY5PDH
New BATCH Ku !!! MUCH IN DEMAND FAST SALE EVERY BATCH HAPPY GOOD EFFECT BIG BATCH !
Contact me on Threema or skype to start big business!!
Hot-sale products:
NEW HOT EUTYLONE WHITE CRYSTAL!!
5cl-adba precursor (semi finished )
5cl-adba raw materials
ADBB precursor (semi finished )
ADBB raw materials
APVP powder
5fadb/4f-adb
Jwh018 / Jwh210
Eutylone crystal
Protonitazene (hydrochloride) CAS: 119276-01-6
Flubrotizolam CAS: 57801-95-3
Metonitazene CAS: 14680-51-4
Payment terms: Western Union,MoneyGram,Bitcoin or USDT.
Deliver Time: Usually 7-15days
Shipping method: FedEx, TNT, DHL,UPS etc.Our deliveries are 100% safe, fast, reliable and discreet.
Samples will be sent for your evaluation!If you are interested in, please contact me, let's talk details.
We specializes in exporting high quality Research chemical, medical intermediate, Pharmaceutical chemicals and so on. Products are exported to USA, Canada, France, Korea, Japan,Russia, Southeast Asia and other countries.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
1. Mr. Osman H. Ali
B.Sc. Microbiology, MPH, HDCH
MORPHOLOGY OF BACTERIA
2. Contents
• Introduction
• Size of Bacteria
• Shape of Bacteria
• Arrangements of Bacterial Cells
• Structure of Bacterial Cell
3. Introduction
• A prokaryotic and single cell microorganism.
• Small in size.
• Don’t have nuclear membranes and also lack membrane
bound organelles.
• Can be able to see by using Microscope.
4. Conti……
• They occur in water, soil, air, food, and all
natural environment. They can survive extremes of temperature,
pH, oxygen, and atmospheric pressure.
5. Size of Bacteria
• Bacteria are very small microorganisms which are visible
under the microscope.
• They are having the size range in microns.
• Bacteria are stained by staining reagents and
then visualised under
(1000X)
high power of
of compound
magnification
microscope.
• An electron microscope is used for clear
visualization of internal structure of bacteria.
6. SHAPE OF BACTERIA
On the basis of shape bacteria are classified as
1. Cocci
2. Bacilli
3. Vibrios
4. Spirilla
5. Spirochetes
6. Actinomycetes
7. Mycoplasma
7.
8. 1. Cocci
• Cocci are small, spherical or oval cells. In greek
‘Kokkos’ means berry. Eg: micrococcus
9. 2. Bacilli
• They are rod shaped cells. Eg: Bacillus anthracis.
• It is derived from greek word “ Bacillus” meaning stick.
• In some of the bacilli the length of cell may be equal to width.
Such bacillary forms are known as coccobacilli. Eg: Bracella.
13. 6. Actinomycetes
• The characteristic shape is due to the presence of
rigid cell wall. Eg: Streptomyces.
• They are branching filamentous bacteria.
• Eg: Streptomyces species.
14. 7. Mycoplasma
• They are cell wall deficient bacteria and hence do not
possess stable morphology. They occur as round or
oval bodies with interlacing filaments.
15. Arrangement of Bacterial Cells
Cocci appears as several
arrangement or grouping.
1.Diplococci
2.Streptococci
3.Tetracocci
4.Staphylococci
5.Sarcinae
characteristics
16. 1. Diplococci
• They split in one plane and remains in pair. Eg:
diplococcus pneumoniae.
17. 2. Streptococci
These cells divide in one planes and remain attached ,
to form chains. Eg: streptococcus lactis.
18. 3. Tetracocci
• They divide in two planes and live in groups of four.
Eg: Gaffyka tetragena.
19. 4. Staphylococci
• Cocci cells divide in three planes in an irregular pattern.
These cells produce bunches of cocci as in grapes. Eg:
staphylococcus aureus, staphylococcus albus.
20. 5. Sarcinae
• Sarcinae cells divide in three planes in a regular
pattern.
• These cells produces a cuboidal arrangement of
group of a eight cells.
• Eg: Micrococcus tetragena.
21. Arrangement of grouping formed by bacilli
species
1. Diplobacilli
2. Streptobacilli
3. Trichomes
Trichomes
Diplobacilli
streptobacilli
23. Flagella
• Flagella are
appendages,
bacteria.
long, slender, thin hair-like cytoplasmic
which are responsible for the motility of
• These are the organs of locomotion.
• They are 0.01 to 0.02 µm in diameter, 3 to 20 µm in length.
• Flagella are made up of a protein- flagellin.
• The flagellum has three basic parts ,
1. Filament
2. Hook
3. Basal body
24. • Filament is the thin, cylindrical, long outermost region with a
constant diameter.
• The filament is attached to a slightly wider hook.
• The basal body is composed of a small central rod inserted
into a series of rings.
• Gram negative bacteria contain four rings as L-ring, P-ring, S-
ring, M-ring whereas gram positive bacteria have only S and M
rings in basal body.
25. Flagella may be seen on bacterial body in following manner.
1. Monotrichous: These bacteria have single polar flagellum. Eg:
vibrio cholera
2. Lophotrichous: These bacteria have two or more flagella only
at one end of the cell. Eg: pseudomonas fluorescence.
3. Amphitrichous: These bacteria have single polar flagella or tuft
of flagella at both poles. Eg :Aquaspirillum serpens.
4. Peritrichous: Several flagella present all over the surface of
bacteria. Eg: Escherichia coli, Salmonella typhi.
26. Pili or fimbriae
• Pili are hair-like microfibrils, 0.5 to 2 µm in length and 5 to 7
nm in diameter.
• They are thinner, shorter and more numerous than flagella.
• They are present only on gram negative cells.
• They are composed of protein known as pillin.
• They are unrelated to motility and are found on motile and non-
motile cells.
27. Conti……
• Fimbriae and pili, these two terms are used interchangeably but
they can be distinguished.
• Fimbriae can be evenly distributed over the entire surface of the
cell or they occurs at the poles of the bacterial cell. Each
bacteria possess 100 to 200 fimbriae.
• Pili are usually longer than fimbriae and number only one or two
per cell.
Function:
• Pili play an important role in attachment to surfaces. Hence pili
is also called organ of adhesion.
28. • The cytoplasmic (plasma) membrane is a thin ( 5 to 10 nm).
• It separates the cell wall and cytoplasm.
• It composed of phospholipids (20 to 30 %) and proteins ( 60 to
70 %).
• Prokaryotic plasma membranes are less rigid than eukaryotic
membrane due to lack of sterols.
Plasma membrane
29. Conti…….
Functions:
1. It acts as a semipermeable membrane controlling the inflow
and outflow of metabolites to and from the protoplasm.
2. It provides the mechanical strength to the bacterial cell.
3. It helps in DNA replication.
4. It contains enzyme, permease, which plays an important role
in the passage of selective nutrients through the membranes.
30. Cytoplasm
• The bacterial cytoplasm is a suspension of organic,
inorganic solutes in a viscous water solution.
• The cytoplasm of bacteria differs from that of
higher eukaryotic microorganisms in not
containing endoplasmic reticulum, Golgi
31. Conti…..
apparatus, mitochondria and lysosomes.
• It contains the ribosomes, proteins and other
water soluble components and reserve material.
• In most bacterial, extrachromosal DNA ( plasmid
DNA ) is also present.
32. Mesosomes
• Mesosomes are respiratory sites of bacteria.
• The mesosomes are attached to the bacterial
chromosomes and is involved in DNA segregation
during cell division.
• They are predominant in Gram positive bacteria.
33. Nucleoid
• The bacterial chromosomes is not surrounded by nuclear
membrane so it is called nucleoid.
• The bacterial chromosomes are made up of double strand
circular DNA.
Intra Cytoplasmic inclusion
Many species of bacteria produce cytoplasmic inclusion
bodies which appears as round granules.
• They are made up of either glycogen or starch.
• They appear reddish when stained with polychrome methylene
34. Capsule
• Bacteria synthesize loose amorphous organic exopolymer
which is deposited outside and tightly to cell wall called
capsules.
• Capsules may be composed of complex polypeptides or
of
polysaccharides. Water (98%) is the main component
bacterial capsule.
35. Conti……..
• Some times the capsular material is loosely associated with the
bacterium, it can be easily washed away. The loose layer is called
slime layer.
• Capsulated bacteria produces smooth colonies and non capsulated
bacteria produces rough colonies on the surface of agar media.
Functions
1. They protect the cell from drying.
2. They protects the bacterial cell against anti-bacterial agents and
phages.
36. Cell wall
• Cell wall is rigid structure which gives definite shape to cell,
situated between the capsule and cytoplasmic membrane.
• It is about 10 – 20 nm in thickness and constitutes 20-30 % of
dry weight of cell.
• The cell wall cannot be seen by direct light microscopy and does
not stain easily by different staining reagents.
37. Conti…….
• The cell wall of bacteria contains diaminopimelic acid (DAP),
muramic acid and teichoic acid. These substances are joined
together to give rise to a complex polymeric structure known as
peptidoglycan or murein or mucopeptide.
• Peptidoglycan is the major constituent of the cell wall of gram
positive bacteria (50 to 90 %) where as in gram negative
bacterial cell wall its presence is only 5 -10 %.
39. A comparison of cell walls of gram positive and gram negative bacteria
40. Functions of cell wall
1. Cell wall is involved in growth and cell division of bacteria.
2. It gives shape to the cell.
3. It gives protection to internal structure and acts as
supporting layer.
4. To prevent rupture of bacteria caused by osmotic pressure
differences between intra cellular and extra cellular
environment.
5. To provide support for flagella.
6. To regulate a certain degree of passage of molecules into
and out of the cell.
7. It serve as the sites of attachment for most bacterial viruses.
41.
42. Ribosomes
• Ribosomes are the center of protein synthesis.
• They are slightly smaller than eukaryotic ribosomes.
• The sedimentation constant is 70s.
• This 70s ribosomes are made up of two subunits namely a
large subunits 50s and a small subunit 30s.
30s
50s
• During active protein synthesis the ribosomes are associated
with mRNA and such associations are called polysomes.
mRNA
Polysomes
43. Spore
• The process of endospore formation is known as sporulation and it
may take 4 to 8 hours in a vegetative cell.
• Endospores are thick-walled, highly refractile bodies that are
produced one per cell.
• Each bacterial spore on germination forms a single vegetative cell.
Therefore, sporulation in bacteria is a method of preservation and not
reproduction.
44. Conti…….
• Spores are extremely resistant to dessication, staining,
disinfecting chemicals, radiation and heat.
• They remain viable for centuries and help bacteria to survive
for long period under unfavorable environment. Endospore
can remain dormant for thousand of years.
• Spores of all medically important bacteria are destroyed by
moist heat sterilization ( autoclave ) at 121 °C for 20 minutes.