Q. Which one of the following statements is correct?
- Bacteria contain cytoplasm but viruses do not
- Bacteria contain mitochondria but viruses do not
- Viruses contain mitochondria but bacteria do not
- Viruses have a cell membrane but bacteria do not
Answer: Bacteria contain cytoplasm but viruses do not
Bacteria are a type of biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometers in length, bacteria have a number of shapes, ranging from spheres to rods and spirals. Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste,[4] and the deep biosphere of the earth's crust. Bacteria also live in symbiotic and parasitic relationships with plants and animals.
The bacterial cell is surrounded by a cell membrane, which is made primarily of phospholipids. This membrane encloses the contents of the cell and acts as a barrier to hold nutrients, proteins and other essential components of the cytoplasm within the cell. Unlike eukaryotic cells, bacteria usually lack large membrane-bound structures in their cytoplasm such as a nucleus, mitochondria, chloroplasts and the other organelles present in eukaryotic cells. However, some bacteria have protein-bound organelles in the cytoplasm which compartmentalize aspects of bacterial metabolisms, such as the carboxysome. Additionally, bacteria have a multi-component cytoskeleton to control the localization of proteins and nucleic acids within the cell and to manage the process of cell division.
Bacteria were first observed by the Dutch microscopist Antonie van Leeuwenhoek in 1676, using a single-lens microscope of his own design.Bacteria are a type of biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometers in length, bacteria have a number of shapes, ranging from spheres to rods and spirals. Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste,[4] and the deep biosphere of the earth's crust. Bacteria also live in symbiotic and parasitic relationships with plants and animals.
The bacterial cell is surrounded by a cell membrane, which is made primarily of phospholipids. This membrane encloses the contents of the cell and acts as a barrier to hold nutrients, proteins and other essential components of the cytoplasm within the cell. Unlike eukaryotic cells, bacteria usually lack large membrane-bound structures in their cytoplasm such as a nucleus, mitochondria, chloroplasts and the other organelles present in eukaryotic cells. However, some bacteria have protein-bound organelles in the cytoplasm which compartmentalize aspects of bacterial metabolisms, such as the carboxysome. Additionally, bacteria have a multi-component cytoskeleton to control the localization of proteins and nucleic acids within the cell and to manage the process of cell division.
Difference between Bacteria and Viruses
- Bacteria and viruses differ in their structure and their response to medications.
- Bacteria are single-celled, living organisms. They have a cell wall and all the components necessary to survive and reproduce, although some may derive energy from other sources. Viruses are not considered to be “living” because they require a host cell to survive long-term, for energy, and to reproduce. Viruses consist of only one piece of genetic material and a protein shell called a capsid. They survive and reproduce by “hijacking” a host cell, and using its ribosomes to make new viral proteins.
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