Cell structure and function
- Nucleolus
- Nucleus
- Ribosomes
- Vesicle
- Rough endoplasmic reticulum(ER)
- Golgi apparatus
- Cytoskeleton
- Smooth(ER)
- Mitochondrion
- Vacoule
- Cytosol
- Lysosome
- Cetrosome
- Cell membrane
Nucleus
Nucleus is a membrane organelle found in eukaryotic cells. It is the main functioning body of the cell. The nuclear material in prokaryotic cells is not enclosed with in membrane to form nucleus which shows the underdeveloped cell structure. Nucleus as I described has three main parts Nuclear membrane, Nucleoplasm and Nucleolus. To get information about these I insist you to read the first part. As we know that nucleus contains the genetic coding in form of DNA molecules bind together to form chromosomes by proteins such as Histones.
Mitochondria range from 0.5 to 1.0 micrometer in diameter. These structures are sometimes described as "cellular power plants" because they generate most of the cell's supply of adenosine triphosphate (ATP), used as a source of chemical energy. In addition to supplying cellular energy, mitochondria are involved in other tasks such as signaling, cellular differentiation, cell death, as well as the control of the cell cycle and cell growth. Mitochondria have been implicated in several human diseases, including mitochondrial disorders and cardiac dysfunction, and may play a role in the aging process. More recent research indicates that autism, especially severe autism, is correlated with mitochondrial defects.
Rough ER
The endoplasmic reticulum (ER) is a type of organelle in the cells of eukaryotic organisms that forms an interconnected network of flattened, membrane-enclosed sacs or tubes known as cisternae. The membranes of the ER are continuous with the outer membrane of the nuclear envelope. Endoplasmic reticulum occurs in most types of eukaryotic cells, including the most primitive Giardia, but is absent from red blood cells and spermatozoa. There are two types of endoplasmic reticulum, rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). The outer (cytosolic) face of the rough endoplasmic reticulum is studded with ribosomes that are the sites of protein synthesis. The rough endoplasmic reticulum is especially prominent in cells such as hepatocytes where active protein synthesis occurs. The smooth endoplasmic reticulum lacks ribosomes and functions in lipid metabolism, carbohydrate metabolism, and detoxification[citation needed] and is especially abundant in mammalian liver and gonad cells. The lacey membranes of the endoplasmic reticulum were first seen in 1945 by Keith R. Porter, Albert Claude, Brody Meskers and Ernest F. Fullam, using electron microscopy.
Lysosome is a membrane-bound cell organelle found in animal cells (they are absent in red blood cells). They are structurally and chemically spherical vesicles containing hydrolitic enzymes, which are capable of breaking down virtually all kinds of biomolecules, including proteins, nucleic acids, carbohydrates, lipids, and cellular debris. They are known to contain more than fifty different enzymes which are all active at an acidic environment of about pH 5. Thus they act as waste disposal system of the cell by digesting unwanted materials in the cytoplasm, both from outside of the cell and obsolete components inside the cell. For this function they are popularly referred to as "suicide bags" or "suicide sacs" of the cell. Further, lysosomes are responsible for cellular homeostasis for their involvements in secretion, plasma membrane repair, cell signalling and energy metabolism, which are related to health and diseases.[1] Depending on their functional activity their sizes can be very different, as the biggest ones can be more than 10 times bigger than the smallest ones. They were discovered and named by Belgian biologist Christian de Duve, who eventually received the Nobel Prize in Physiology or Medicine in 1974.
Ribosomes
Ribosomes are complex molecular bodies which are found in all living cells and are basic bodies responsible for protein synthesis as directed by messenger RNA or mRNA. These structures are produced by nucleolus and are conducted by rough ER into the the cytoplasm. As ribosomes are made up of complex RNAs so they are called ribonucleoprotein. Each ribosome is divided into two subunits: a smaller subunit which binds to the mRNA pattern, and a larger subunit which binds to the tRNA and the amino acids. When a ribosome finishes reading an mRNA molecule, these two subunits split apart. Ribosomes are ribozymes, because the catalytic peptidyl transferase activity that links amino acids together is performed by the ribosomal RNA.
BLUE (SMALLER UNITS)Mitochondrion
The mitochondrion (plural mitochondria) is a membrane-bound organelle found in most eukaryotic cellsMitochondria range from 0.5 to 1.0 micrometer in diameter. These structures are sometimes described as "cellular power plants" because they generate most of the cell's supply of adenosine triphosphate (ATP), used as a source of chemical energy. In addition to supplying cellular energy, mitochondria are involved in other tasks such as signaling, cellular differentiation, cell death, as well as the control of the cell cycle and cell growth. Mitochondria have been implicated in several human diseases, including mitochondrial disorders and cardiac dysfunction, and may play a role in the aging process. More recent research indicates that autism, especially severe autism, is correlated with mitochondrial defects.
Rough ER
The endoplasmic reticulum (ER) is a type of organelle in the cells of eukaryotic organisms that forms an interconnected network of flattened, membrane-enclosed sacs or tubes known as cisternae. The membranes of the ER are continuous with the outer membrane of the nuclear envelope. Endoplasmic reticulum occurs in most types of eukaryotic cells, including the most primitive Giardia, but is absent from red blood cells and spermatozoa. There are two types of endoplasmic reticulum, rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). The outer (cytosolic) face of the rough endoplasmic reticulum is studded with ribosomes that are the sites of protein synthesis. The rough endoplasmic reticulum is especially prominent in cells such as hepatocytes where active protein synthesis occurs. The smooth endoplasmic reticulum lacks ribosomes and functions in lipid metabolism, carbohydrate metabolism, and detoxification[citation needed] and is especially abundant in mammalian liver and gonad cells. The lacey membranes of the endoplasmic reticulum were first seen in 1945 by Keith R. Porter, Albert Claude, Brody Meskers and Ernest F. Fullam, using electron microscopy.
Lysosomes
Lysosome is a membrane-bound cell organelle found in animal cells (they are absent in red blood cells). They are structurally and chemically spherical vesicles containing hydrolitic enzymes, which are capable of breaking down virtually all kinds of biomolecules, including proteins, nucleic acids, carbohydrates, lipids, and cellular debris. They are known to contain more than fifty different enzymes which are all active at an acidic environment of about pH 5. Thus they act as waste disposal system of the cell by digesting unwanted materials in the cytoplasm, both from outside of the cell and obsolete components inside the cell. For this function they are popularly referred to as "suicide bags" or "suicide sacs" of the cell. Further, lysosomes are responsible for cellular homeostasis for their involvements in secretion, plasma membrane repair, cell signalling and energy metabolism, which are related to health and diseases.[1] Depending on their functional activity their sizes can be very different, as the biggest ones can be more than 10 times bigger than the smallest ones. They were discovered and named by Belgian biologist Christian de Duve, who eventually received the Nobel Prize in Physiology or Medicine in 1974.
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