The basics about Cells
It has been quite long since I learnt about cells during Sec 1. Still, I have some interest for it, so here's a basic overview of cells I have read up on as a summary.
Cells are the primary unit of life. There are millions of different types of cells on Earth. Some cells can also be organisms themselves, other than being part of a larger organism, like the human body. All types of cells are special in their features and functions.
Cells were first discovered by Robert C. Hooke, a polymath, when he cut a thin piece of cork and discovered empty spaces contained by walls. He called these cells. All cells fall into two major classifications: eukaryotes and prokaryotes. Eukaryotes are distinct from prokaryotes for containing membrane-bound components, and are significantly larger(about. 15times) wider. Prokaryotes are bacteria and archaea while eukaryotes are other organisms' cells.
Cells are the primary unit of life. There are millions of different types of cells on Earth. Some cells can also be organisms themselves, other than being part of a larger organism, like the human body. All types of cells are special in their features and functions.
Cells were first discovered by Robert C. Hooke, a polymath, when he cut a thin piece of cork and discovered empty spaces contained by walls. He called these cells. All cells fall into two major classifications: eukaryotes and prokaryotes. Eukaryotes are distinct from prokaryotes for containing membrane-bound components, and are significantly larger(about. 15times) wider. Prokaryotes are bacteria and archaea while eukaryotes are other organisms' cells.
Some parts of an animal cell:
cell membrane - a layer of protein and fat(lipid) that surrounds the cell. The cell membrane is semipermeable, allowing only some substances to pass into the cell.
cytoplasm - the jelly-like material outside the cell nucleus in which the organelles are located.
Golgi body - (Golgi apparatus/golgi complex) a flattened, layered, sac-like organelle that is located near the nucleus. It produces the membranes that surround the lysosomes. The Golgi body packages proteins and carbohydrates into membrane-bound vesicles for "export" from the cell.
lysosome - (also called cell vesicles) round organelles surrounded by a membrane and containing digestive enzymes. This is where the digestion of cell nutrients takes place.
mitochondrion - spherical to rod-shaped organelles with a double membrane. The inner membrane is infolded many times, forming a series of projections (called cristae). The mitochondrion converts the energy stored in glucose into ATP (adenosine triphosphate) for the cell.
nuclear membrane - the membrane that surrounds the nucleus.
nucleolus - an organelle within the nucleus - it is where ribosomal RNA is produced. Some cells have more than one nucleolus.
nucleus - spherical body containing many organelles, including the nucleolus. The nucleus controls many of the functions of the cell and contains DNA in chromosomes.
ribosome - small,RNA-rich cytoplasmic granules organelles which make protein.
vacuoles - fluid-filled, membrane-surrounded cavities inside a cell. The vacuole fills with food being digested and waste material .
Some parts of a plant cell:
cell membrane, cytoplasm, mitochondrion
cell wall - a thick, rigid membrane that surrounds a plant cell. This layer of cellulose fiber gives the cell most of its support and structure. The cell wall also bonds with other cell walls to form the structure of the plant.
chloroplast - an elongated or disc-shaped organelle containing chlorophyll for photosynthesis. (in which energy from sunlight is converted into chemical energy)
vacuole - a large, membrane-bound space within a plant cell that is filled with fluid. Most plant cells have a single vacuole that takes up much of the cell. It helps maintain the shape of the cell.
cell membrane - a layer of protein and fat(lipid) that surrounds the cell. The cell membrane is semipermeable, allowing only some substances to pass into the cell.
cytoplasm - the jelly-like material outside the cell nucleus in which the organelles are located.
Golgi body - (Golgi apparatus/golgi complex) a flattened, layered, sac-like organelle that is located near the nucleus. It produces the membranes that surround the lysosomes. The Golgi body packages proteins and carbohydrates into membrane-bound vesicles for "export" from the cell.
lysosome - (also called cell vesicles) round organelles surrounded by a membrane and containing digestive enzymes. This is where the digestion of cell nutrients takes place.
mitochondrion - spherical to rod-shaped organelles with a double membrane. The inner membrane is infolded many times, forming a series of projections (called cristae). The mitochondrion converts the energy stored in glucose into ATP (adenosine triphosphate) for the cell.
nuclear membrane - the membrane that surrounds the nucleus.
nucleolus - an organelle within the nucleus - it is where ribosomal RNA is produced. Some cells have more than one nucleolus.
nucleus - spherical body containing many organelles, including the nucleolus. The nucleus controls many of the functions of the cell and contains DNA in chromosomes.
ribosome - small,RNA-rich cytoplasmic granules organelles which make protein.
vacuoles - fluid-filled, membrane-surrounded cavities inside a cell. The vacuole fills with food being digested and waste material .
Some parts of a plant cell:
cell membrane, cytoplasm, mitochondrion
cell wall - a thick, rigid membrane that surrounds a plant cell. This layer of cellulose fiber gives the cell most of its support and structure. The cell wall also bonds with other cell walls to form the structure of the plant.
chloroplast - an elongated or disc-shaped organelle containing chlorophyll for photosynthesis. (in which energy from sunlight is converted into chemical energy)
vacuole - a large, membrane-bound space within a plant cell that is filled with fluid. Most plant cells have a single vacuole that takes up much of the cell. It helps maintain the shape of the cell.
Organisms contain many different types of cells that perform many different functions. Similar cells group together to form tissues, which in tun form organs, which in turn form systems.
Special cell- stem cell
Stem cells are a class of undifferentiated cells that are able to differentiate into specialized cell types. Commonly, stem cells come from two main sources: embryonic stem cells and adult stem cells . In a developing embryo, stem cells can differentiate into all of the specialised embryonic tissues. In adult organisms, stem cells act as a repair system for the body, replenishing specialized cells, but also maintain the normal turnover of blood, skin, and intestinal tissues. Stem cells are very useful these days as they prove as medical cures for people, especially the disabled. They are expected to be used in future medical therapies.
Want to know more? Watch this video by the Irish Stem Cell Foundation:
Stem cells are a class of undifferentiated cells that are able to differentiate into specialized cell types. Commonly, stem cells come from two main sources: embryonic stem cells and adult stem cells . In a developing embryo, stem cells can differentiate into all of the specialised embryonic tissues. In adult organisms, stem cells act as a repair system for the body, replenishing specialized cells, but also maintain the normal turnover of blood, skin, and intestinal tissues. Stem cells are very useful these days as they prove as medical cures for people, especially the disabled. They are expected to be used in future medical therapies.
Want to know more? Watch this video by the Irish Stem Cell Foundation:
Article (ScienceDaily):
Now that we know a little about cells, let's move on to a well-known disease: Alzheimer's, which involves a work with brain cells. Everyone has thought that there was no hope for affected people, however, see if there is a ray of hope here.
Simply speaking, Alzheimer's disease seriously affects a person's intellectual abilities and causes him/her to suffer memory loss. The greatest known factor is old age, as most people with Alzheimer's are 65 years old and above. However, it is not just a disease of old age. It also worsens over time, so someone diagnosed with Alzheimer's has to find ways to slow the progress.
The article says that the two main agents involved in causing Alzheimer's are the amyloid beta precursor protein (APP) and the beta secretase enzyme (BACE1). They follow a different path through the brain cells to meet up, causing the development of the disease. The disease then slowly destroys brain cells in the deep part of the brain which serve for memory and knowledge.
Therefore, closing off or rerouting the path which the enzyme travels to meet the protein may stop the progress of the disease. There still needs to be much more research, so it is not a cure yet. Nevertheless, I wish for this research to break new grounds and help affected people recover from this illness. I believe that with such modern technology and facilities in place, progress would come encouragingly rapidly.
Simply speaking, Alzheimer's disease seriously affects a person's intellectual abilities and causes him/her to suffer memory loss. The greatest known factor is old age, as most people with Alzheimer's are 65 years old and above. However, it is not just a disease of old age. It also worsens over time, so someone diagnosed with Alzheimer's has to find ways to slow the progress.
The article says that the two main agents involved in causing Alzheimer's are the amyloid beta precursor protein (APP) and the beta secretase enzyme (BACE1). They follow a different path through the brain cells to meet up, causing the development of the disease. The disease then slowly destroys brain cells in the deep part of the brain which serve for memory and knowledge.
Therefore, closing off or rerouting the path which the enzyme travels to meet the protein may stop the progress of the disease. There still needs to be much more research, so it is not a cure yet. Nevertheless, I wish for this research to break new grounds and help affected people recover from this illness. I believe that with such modern technology and facilities in place, progress would come encouragingly rapidly.