Morphology and Classification of Dairy Bacteria
Questions:
1. Name the different species of bacteria based on their physiological nature. ’22 (05)/
Classify bacteria with examples on the basis of biochemical activities. ’21/ Classify
dairy bacteria with examples and conditions based on biochemical activities in a
tabular form.’23 (05)
2. Mention the causative organisms of Gas production, bitterness and putrefaction, sweet
curdling, ropiness, unclean flavor, late gas defect, and floating curd in dairy
products.’20 (05)
3. What do you mean by microorganisms? Shortly describe the biological properties of
microorganisms.’20,’18 (5)
4. Define bacterial taxonomy, nomenclature, and identification. What are the importance
and ranks/levels of bacterial taxonomy in Dairy Microbiology?’20 (05)
5. Draw and label the schematic view of a bacterial cell with the function of its
constituents.’22 (05)
6. Describe the shape and arrangement of bacteria with figures.’17 (5)
7. Differentiate between Gram-positive and Gram-negative bacteria. Narrate the flow
diagram of Gram staining.’17 (5)
8. Define Dairy microbiology. What do you mean by bacteria, yeast, and mould? ’17 (5)
1
, Biological properties of Bacteria:
1. Specific Size: Most bacteria fall into the range of 1 to 5 microns in length or diameter and 0.5 to 1.0
microns in width.
2. Cellular Structure: They possess rigid, well-differentiated cell walls, a characteristic associated with
plant cells rather than animal cells.
3. Algal Similarity: Many bacteria are morphologically similar to blue-green algae but are distinguished by
their lack of photosynthetic pigments
4. Holophytic Nutrition: Bacteria are holophytic, meaning they absorb nutrients only in solution. They do
not ingest nutrients in particulate form (holozoic), distinguishing them from organisms such as amoebas.
5. Specific Surface: Bacteria possess a high surface-to-volume ratio, known as "specific surface". Apart
from viruses and rickettsiae, bacteria have a greater surface-to-volume ratio than any other group of living
organisms.
6. Division Mechanism: Bacteria reproduce through binary fission (grow and split). Under ideal conditions,
some species divide once every 20–30 minutes.
2
Questions:
1. Name the different species of bacteria based on their physiological nature. ’22 (05)/
Classify bacteria with examples on the basis of biochemical activities. ’21/ Classify
dairy bacteria with examples and conditions based on biochemical activities in a
tabular form.’23 (05)
2. Mention the causative organisms of Gas production, bitterness and putrefaction, sweet
curdling, ropiness, unclean flavor, late gas defect, and floating curd in dairy
products.’20 (05)
3. What do you mean by microorganisms? Shortly describe the biological properties of
microorganisms.’20,’18 (5)
4. Define bacterial taxonomy, nomenclature, and identification. What are the importance
and ranks/levels of bacterial taxonomy in Dairy Microbiology?’20 (05)
5. Draw and label the schematic view of a bacterial cell with the function of its
constituents.’22 (05)
6. Describe the shape and arrangement of bacteria with figures.’17 (5)
7. Differentiate between Gram-positive and Gram-negative bacteria. Narrate the flow
diagram of Gram staining.’17 (5)
8. Define Dairy microbiology. What do you mean by bacteria, yeast, and mould? ’17 (5)
1
, Biological properties of Bacteria:
1. Specific Size: Most bacteria fall into the range of 1 to 5 microns in length or diameter and 0.5 to 1.0
microns in width.
2. Cellular Structure: They possess rigid, well-differentiated cell walls, a characteristic associated with
plant cells rather than animal cells.
3. Algal Similarity: Many bacteria are morphologically similar to blue-green algae but are distinguished by
their lack of photosynthetic pigments
4. Holophytic Nutrition: Bacteria are holophytic, meaning they absorb nutrients only in solution. They do
not ingest nutrients in particulate form (holozoic), distinguishing them from organisms such as amoebas.
5. Specific Surface: Bacteria possess a high surface-to-volume ratio, known as "specific surface". Apart
from viruses and rickettsiae, bacteria have a greater surface-to-volume ratio than any other group of living
organisms.
6. Division Mechanism: Bacteria reproduce through binary fission (grow and split). Under ideal conditions,
some species divide once every 20–30 minutes.
2
