Botany · Class 12 Science
Ch 13Bacteria — Class 12 Botany, concept-first.
Bacteria are microscopic, single-celled organisms and they are found essentially everywhere on Earth - in soil, water, air, hot springs, deep in rock, and in and on the bodies of other living things - a distribution so universal that it is described as ubiquitous.
Key concepts
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Microbiology and the Importance of Bacteria to Humans
Microbiology is the branch of biology devoted to the study of micro-organisms - living things too small to be seen with the unaided eye, including bacteria, which are found in essentially every habitat on Earth, from soi…
Most relevant Q&A
- Correct the common misconception that all bacteria cause disease.Free
- In human faeces, bacteria make up about one-third of the roughly 50 g excreted per day, and each bacterial cell weighs about 1x10^-12 g. Est…Preview
- What is meant by the ubiquitous occurrence of micro-organisms?Free
- Explain the importance of Microbiology.Free
- Define Microbiology.Free
Chapter contents
The NCERT structure, section by section. Open a section to see its questions, then read the concept-first solution.
Morphology of Bacteria
Bacteria are microscopic, single-celled organisms and they are found essentially everywhere on Earth - in soil, water, air, hot springs, deep in rock, and in and on the bodies of other living things -…
Bacterial Cell Structure and Nutrition
A typical bacterial cell is enclosed by a cell wall and, within it, a plasma membrane, surrounding the cytoplasm in which the cell's metabolic activities take place.
Reproduction - Sexual Reproduction, Conjugation, Transformation, Transduction
While bacteria multiply chiefly by simple asexual division, they can also exchange genetic material between two cells in ways that resemble sexual reproduction in the sense that DNA from one cell (the…
The Importance of Bacteria to Humans
21 QBacteria affect human life in ways that are both beneficial and harmful, which is why they are often summed up as being both friends and foes of man.
+−Very Short Answer Questions10 questions
- Q1What is meant by the ubiquitous occurrence of micro-organisms?Free
- Q2Define Microbiology.Free
- Q3Name the intestinal bacterium that is widely used as a host organism in biotechnology.Free
- Q4What are pleomorphic bacteria? Give an example.Preview
- Q5What is a sex pilus? What is its function?Preview
- Q6What is a genophore?Preview
- Q7What is a plasmid? What is its significance?Preview
- Q8What is conjugation? Who discovered it, and in which organism?Preview
- Q9What is transformation? Who discovered it, and in which organism?Preview
- Q10What is transduction? Who discovered it, and in which organism?Preview
+−Short Answer Questions6 questions
- Q1Explain the importance of Microbiology.Free
- Q2Describe the classification of bacteria based on their morphology (shape).Free
- Q3Describe the classification of bacteria based on the number and distribution of flagella.Preview
- Q4Describe the nutritional classification of bacteria based on their source of energy and carbon.Preview
- Q5What are chemoheterotrophs?Preview
- Q6Explain the process of conjugation in bacteria.Preview
+−Long Answer Questions2 questions
+−Intext Questionsi3 questions
Sample & Board Papers
Sample papers and previous-year board questions for this subject.
+−Show 7 questionsHide questions7 questions
- Q1What are pleomorphic bacteria? Give an example.Preview
- Q2What are pleomorphic bacteria? Give an example.Preview
- Q3What are porins? What role do they play in diffusion?Preview
- Q4Explain the conjugation in bacteria.Preview
- Q5What are Pleomorphic bacteria ? Give an example.Preview
- Q6What is a genophore?Preview
- Q7How are bacteria classified on the basis of number and distribution of flagella?Preview