Cell membrane

Cell membrane

Cell membrane is a "thin semi-permeable membrane" that it does surrounds the "cytoplasm" of a cell the outside of the cell in other words, enclosing its contents. 

Its function is to protect the integrity of the interior of the cell by allowing certain substances into the cell, while keeping other substances out. It also serves as a base of attachment for the "cytoskeleton" in some organisms and the cell wall in others. 

The cell membrane also serves to help support the cell and help maintain its shape.

The cell membrane is primarily composed of a mix of proteins and lipids. While lipids help to give membranes their flexibility, proteins monitor and maintain the cell's chemical climate and assist in the transfer of molecules across the membrane.

Phospholipids are a major component of cell membranes. They form a lipid bilayer in which their hydrophillic that is attracted to water, head areas spontaneously arrange to face the aqueous cytosol and the extracellular fluid, while their hydrophobic is repelled by water, tail areas face away from the cytosol and extracellular fluid. The lipid bilayer is semi-permeable, allowing only certain molecules todiffuseacross the membrane.

Subcellular components

Subcellular components

(Information about Subcellular components)

Subceullar compartments is the study of efficency and diviced labor within the cell. Just as our society has professions in which people do a specific job very well. The cell create subregions, each of which allows certain cells functions for operating more effectively. Like subdivision of cells into discrete compartments or parts enables the cells to create specialised environments for specific functions. 

These compartments can be organelles to specific structures that it take on sets of tasks within the cell or they can be local regions of the cell defined by the concentration of molecules or distinct physical characteristics and proportions

A only one challenge for subcellular compartments it is how to get materials in and out across the membranes, and each compartment has its own solution. 

The complexity of the structures ranges from mitochondria and plastids with their own DNA and ribosomes, to the Golgi apparatus with its multiple cisternae, to fairly simple vacuoles and vesicles. In addition to the membrane-bound structures, eukaryotes also have a complex cytoskeleton made of three distinctly different components: microtubules, actin filaments, and intermediate filaments. Each of the three plays a role in maintaining cell shape, and microtubules and actin are also involved in internal transport as well as cell motility. 

Defects in any of these structures may lead to clinical disorders. For example, altered intermediate filaments in the nuclear envelope causes a cardiomyopathy, mitochondrial defects can lead to a variety of neuromuscular disorders, and mutations in cilia or flagella may lead to polycystic kidney disease or sterility.

Eukaryotic cells

Eukaryotic cells

 Eukaryotic cells Information 

Eukaryotic cells that came from the Greek meaning "truly nuclear", it does comprise all of the life kingdoms except "monera". They can be easily distinguished through a membrane-bound nucleus.

Type of eurkaryotic -

1. Plants 
2. Animals,
3. Fungi
4. Slime moulds p
5. Protozoa
6. Algae

These cells are about 15 times wider than a typical prokaryote and can be as much as 1000 times greater in volume. The major difference between prokaryotes and eukaryotes is that eukaryotic cells contain "membrane bound" compartments in which specific metabolic activities take place. Most important among these is a cell nucleus, a membrane-delineated compartment that houses the eukaryotic cell's DNA.

Eukaryotic cells also contain many internal membrane-bound structures called organelles. These organelles such as the mitochondrion or chloroplast serve to perform metabolic functions and energy conversion. Other organelles like intracellular filaments provide structural support and cellular motility. The function of individual organelles is described in detail in the Cell Anatomy Section.

1. This nucleus gives the eukaryote its name, which means "true nucleus." Other differences include:
2. The plasma membrane resembles that of prokaryotes in function, with minor differences in the setup. Cell walls may or may not be present.
3. The eukaryotic DNA is organized in one or more linear molecules, called chromosomes, which are associated with histone proteins. All chromosomal DNA is stored in the cell nucleus, separated from the cytoplasm by a membrane. Some eukaryotic organelles such as mitochondria also contain some DNA.
4. Many eukaryotic cells are ciliated with primary cilia. Primary cilia play important roles in chemosensation, mechanosensation, and thermosensation. Cilia may thus be "viewed as sensory cellular antennae that coordinate a large number of cellular signaling pathways, sometimes coupling the signaling to ciliary motility or alternatively to cell division and differentiation."
5. Eukaryotes can move using motile cilia or flagella. The flagella are more complex than those of prokaryotes.

Prokaryotic Cells

Prokaryotic Cells

                                                                                                                                                                          (Information about Prokaryotic cell)



Cells that doesn't have enough membrance-bound nucleus are called "Prokaryotes" That it passed down to the generations from greek meaning "Nuckei". Cells like these have few internal structures that are distinguishable under a microscope only, it cannot be seen by your eyes unless some engine to help you out. Cells in the "Monera" kingdom such as a bacteria and cyanobacteria, also are know with other name as "Blue-Green algae" are also prokaryotes.

These "Prokaryotic" cells differ significantly from "eukaryotic cells". they doesn't have membrane-bound nucleus and instead of having "Chromosomal DNA", their genetic information is in a circular loop called "plasmid".

Bacterial cells are very small, roughly the size of an animal mitochondrion, it is also about 1-2µm in diameter and 10 µm long. 

Prokaryotic cells feature three major shapes -

1. Rod shaped
2. Spherical
3. Spiral.

Instead of going through elaborate replication processes like "eukaryotes", bacterial cells divide by binary fission.

Cells and History of Cells(Useful information)

Cell

Information about Cell (Useful information)

Cell is a basic structural and fictional unit of all things that living in organism, it is also the most smallest thing unit of life that is classified as a living thing. Except viruses which they consists only from DNA or RNA covered by protein and lipids and is often called the building of life. 

Organisms can be classified as unicellular, which consisting of a single cell, including the most bacteria, or multicellular, including plants and animals. Us humans contain about 100 trillion cells or so, most plant and animals cells are between 1 and 100 micrometers and therefore are visible only under microscope only, its impossible to see those without an engine that could zoom in.

History about Cells

                                                                 History of cells(Useful information)

Cells emerged on planet earth at least 4.0–4.3 billion years ago, so they are pretty old from the existence. The cell was discovered long ago by Robert Hooke in year 1665, so is pretty hard at that time that for someone even with not much of engine could discovere such a thing. The cell theory, first developed in 1839 that at that years was still early for some machine to help, but we had something at that time, this was discovered by Matthias Jakob Shkeiden and Theodor Schwannm, states that all organsims are composed for one or more cells, that all cells come from "Pre-existing cells", that a vital functions of an organsims occur within cells, and that all cells contain the hereditary information necessary for a regulating cells function and for transmitting information to the next generation of cells, like us humans tell stories to the younger nce's for spreading them for the new generations. 

The world cell comes from the Latin "Cella", meaning "Small room". the descriptive term for the smallest living biologicial strucutre was coined by  Robert Hooke in a book he published in 1665 when he compared the cork cells he saw through his microscope to the small rooms monks lived in.