You all know that air contains lots of germs. Can you recollect a few examples?
Yes, bacteria. Have you ever wondered why we are not able to see bacteria? Why are they small and we are large? Who came first on Earth? Animals, plants or bacteria.
Do these questions also come to your mind? If yes then how to find an answer to them? Let's go through the article and understand more about bacteria.
Cell is considered as the basic unit of life. There are two basic types of cells as follows based on the nuclear complexity and presence of cell organelles:
The distinguishing features of prokaryotes are as follows:
Prokaryotic cell size ranges within a few micrometres. Mycoplasma are the smallest known prokaryotes, being 0.1 to 1µm. The small size of prokaryotic cells allows the ions and organic molecules to diffuse easily and rapidly throughout the other parts of the cell without involving a complex transportation machinery.
Question1. Which of these structures play an important role in bacterial transformation?
B. Cell membrane
D. Genomic DNA
Answer: In many prokaryotes some small, circular, double stranded DNA molecules are present lying in the cytoplasm in addition to their prochromosome. These are called plasmids. Plasmids are responsible for the presence of various phenotypic features in bacteria such as antibiotic resistance. They also monitor bacterial transformation with foreign DNA. Hence option a is correct.
Question2. Identify the cell organelle which is present in both prokaryotic and eukaryotic cells.
B. Endoplasmic reticulum
Answer: Prokaryotes and eukaryotes are the two different types of cells based on the complexity and presence of cell organelles. Ribosomes are present in both prokaryotes and eukaryotes. In prokaryotes they are of 70S type whereas in eukaryotes they are of 80S type. Both prokaryotic and eukaryotic ribosomes perform protein synthesis.
Question3. Which of these is not a basic shape of bacteria?
Answer: Triangular shape is not basically found in any prokaryotes. Prokaryotic cells can be commonly found in the following shapes:
Question4. Why are prokaryotes important?
Question1. How are prokaryotes able to live without a nucleus?
Answer: In prokaryotes there is no nuclear membrane, because there is no proper nucleus. The DNA concentrates in the middle of the cytoplasm in a region called a nucleoid. Therefore, it is possible for prokaryotes to live without a nucleus.
Question2. What qualities make it possible for prokaryotic cells to survive?
Answer: All prokaryotes have some specialised features which help them to survive. These are enlisted below:
Question3. Do prokaryotic cells possess genetic material as DNA?
Answer: Yes, prokaryotic cells have a single circular DNA which is in direct contact with the cytoplasm. The genetic material is concentrated in a region called nucleoid.
Question4. What advantage do prokaryotes have by being small?
Answer: The size of Prokaryotes ranges from 0.1 - 5 μm in diameter. Their small size benefits them in many ways. It allows the quick entrance and diffusion of molecules and ions. It allows easy elimination of waste products from the cell. It allows them to remain in the air or attached to body surfaces without notice.
|The Living World||Biological Classification||Plant Kingdom|
|Animal Kingdom||Morphology of Flowering Plants||Anatomy of Flowering Plants|
|Structural Organization in Animals||Cells: The Unit of Life||Biomolecules|
|Cell Cycle and Division||Transport in Plants||Mineral Nutrition|
|Photosynthesis in Higher Plants||Respiration in Plants||Plant Growth and Development|
|Digestion and Absorption||Breathing and Exchange of Gases||Body Fluids and Circulation|
|Excretory Products and their Elimination||Locomotion and Movement||Neural Control and Coordination|
|Chemical Coordination and Integration|