1. © 2007, YCMOU. All Rights Reserved.1 Online Counseling Resource YCMOU ELearning Drive… School of Architecture, Science and Technology Yashwantrao Chavan Maharashtra Open University, Nashik – 422222, India

2. © 2007, YCMOU. All Rights Reserved.2 OC-SBT081-CP01-01 Introduction Programmes and Courses  SEP – SBT081 – Unit 01

3. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.3 Credits  Academic Inputs by Arun Punaji More. M.Sc. (Microbiology) Experience: 11 Years arunmesh@hotmail.com

4. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.4 How to Use This Resource  Counselor at each study center should use this presentation to deliver lecture of 40-60 minutes during Face-To-Face counseling.  Discussion about students difficulties or tutorial with assignments should follow the lecture for about 40-60 minutes.  Handouts (with 6 slides on each A4 size page) of this presentation should be provided to each student.  Each student should discuss on the discussion forum all the terms which could not be understood. This will improve his writing skills and enhance knowledge level about topics, which shall be immensely useful for end exam.  Appear several times, for all the Self-Tests, available for this course.  Student can use handouts for last minutes preparation just before end exam.

5. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.5 Learning Objectives  After studying this module, you should be able to: Describe Morphological features of bacteria. State examples of bacteria showing different types of morphology. Classify bacteria depending upon their morphology.

6. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.6 Introduction  Bacteria exhibit variety of morphological forms.  The morphological forms of bacteria can be used in identification of the bacterial species.  Identification of bacteria is essential to classify bacteria, to diagnose a pathogenic bacteria in a particular disease for proper treatment of the disease.  It is therefore interesting to know the different morphological features of bacteria.

7. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.7 Morphology of Bacteria-1  Bacteria exhibit various shapes and range from 1 μ to 10 μ.  The bacteria show three basic shapes such as  Rod shaped bacteria or bacilli,  spherical or cocci shaped bacteria and  Spiral shaped bacteria.  Bacteria show some slight variations in these shapes.  For examples rod shaped bacteria show slight curved ends giving them comma shaped appearance; this is called as comma shaped bacteria.

8. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.8 Morphology of Bacteria-2  The typical morphological features of bacteria are shown in the following figure.

9. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.9 Morphology of Bacteria-3  Vibrio cholerae is example of comma shaped bacteria.  Some bacteria show shapes intermediate between spherical and rods; these are called as cocco- bacilli.  Spirilla and spirochetes are examples of spiral bacteria.  Besides these shapes, bacterial morphology is also described with their some special appendages such as pilli, flagella, and resistant forms, spores.

10. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.10 Morphology of Bacteria-4  The motility of bacteria can be seen by hanging drop technique and is used to identify and classify bacteria into motile and non motile bacteria. Flagellum is organ of motility and give bacteria capability to move toward nutrient riched environment for their survival Fig: Bacterial cell with polar flagella

11. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.11 Morphology of Bacteria-5  Morphology of bacteria can be observed after staining them with Gram's stains under compound microscope.  Here the bacilli are arranged in chains and endospores can also be seen. Fig: Bacilli stained with Gram's stain.

12. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.12 Morphology of Bacteria-6  Spherical or cocci shaped bacteria:- The bacteria which show spherical morphology are called as cocci. Cocci show different cell arrangements which help further to classify them into two genus i. e. staphylococci and streptococci. The cocci which appear in bunches are called as Saphylococci. The cocci which appear in chains are called as Streptococci. Streptococci and Staphylococci are Gram positive bacteria. Many species of streptococci possess capsule which is a major virulence factor of these bacteria.

13. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.13 Morphology of Bacteria-7  Some bacteria show intermidiate morphology between rod and cocci; these are called as coccobacilli.  Enterobacter earogenes are coccobacilli; they one of the major causative organisms of nosocomial infections.

14. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.14 Morphology of Bacteria-8  Gram staining of bacteria culture differentiate the rod shaped bacteria from the spherical shaped bacteria. Fig: Gram stained smear of rod shaped and spherical shaped bacteria.

15. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.15 Morphology of Bacteria-9  Corynebacteria show pleomorphic morphology.  Following Figure shows Corynebacteria diphtheria arranged in chines letter forms. Fig: Corynebacteria diphtheriae

16. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.16 Morphology of Bacteria-10  Though the majority of cocci are Gram positive by nature there are few exception.  The species of Niesseria are Gram negative bacteria which appear in pairs; therefore called as Gram negative diplococci.  This typical morphology of Niesseria in urethral pus formed a primitive diagnosis of disease, gonorrhea.

17. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.17 Morphology of Bacteria-11  The genus Niesseria include two medically important pathogens i.e. N. gonococci and N. meningitidis.  The gonococci show typical kidney shaped or bean shaped morphology as shown below. Fig: Bean shaped gonococci arranged as dipococci.

18. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.18 Morphology of Bacteria-12  Spiral bacteria:- Spirilla are spiral stiff bacteria. Fig: spirilla

19. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.19 Morphology of Bacteria-13  Spiral shaped bacteria:- Spirochete is another example of spiral shaped bacteria. Unlike the spirilla they are flexible. The spirochete has three genera:  Treponema  Borrelia  Leptospira

20. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.20 Morphology of Bacteria-14  Coccobacilli:- Bacilli of yersenia pestis are causative agents of bubonic plague. Their another characteristic feature is that they show bipolar staining giving them Safety pin like appearance as shown in the figure. Fig : yerseneia pestis, coccobacilli

21. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.21 Morphology of Bacteria-15  Bacilli of Mycobacteria appear as long slender rods as shown below. Fig: Mycobacteria tuberculosis

22. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.22 What We Learn...  Different morphological formed of bacteria.  How morphology of bacteria help to classify bacteria into different groups.  How the morphology of bacteria help in the diagnosis of some diseases.  How to study morphology of bacteria.

23. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.23 Critical Thinking Questions  Why bacteria are stained to study their morphology?

24. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.24 Hints For Critical Thinking Questions  Bacterial cells are colorless, and having no contrast with their surrounding.

25. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.25 Study Tips  Book Title: Title:Microbiology Author: Author: Robert W Bauman Publication: Publication: Benjamin Cummings, San Francisco  Book Title: Title: Microbiology, An Introduction Author: Author: Tortora and et al. Publication: Publication: Pearson education, Singapore

26. © 2007, YCMOU. All Rights Reserved.26 End of the Presentation Thank You!