Structure and Function of Parts Cell
A. Cell membrane ( Plasma Membrane )
The cell membrane is the outermost part of the cell . Its functions are as follows .
Control or control the exchange of substances between the cytoplasm and its environment .
Be a reaction , such as reaction to sunlight and oxides reactions in respiration .
As a recipient of excitatory receptors or from outside , such as hormones and other chemicals , both of these substances from the environment outside the cell or other parts of the cell itself .
As a protective cell that the cell contents are not out to leave the cell .
Control substances will go and who will come out leaving the cytoplasm .
Cell membranes are composed of lipids , proteins , and carbohydrates . Especially in the form fospolipid lipid molecules that are amphiphilic molecules containing any means " head " and a hydrophilic " tail " hydrophobic . Cell membrane may serve as a protective cell by forming a phospholipid bilayer in which hidrpfilik head facing the water on each side , while the hydrophobic tails shielded from contact with the water .
Has two types of membrane proteins , namely integral and peripheral proteins . Integral proteins that penetrate between the layers of phospholipids , serve as a transport that carries dissolved substances the cell needs . Meanwhile, the protein attached poriferal phospholipid layer .
In the cell facing out cell , carbohydrates are attached to proteins or phospholipid head . Carbohydrates that bind to a protein called glycoprotein , whereas binding to phospholipids called glikopid . Cell membrane actively determine which substances can be passed through and at the same time hold the substances which can not be passed. Based on this fact , scientists refer to it as a semi-permeable membrane that is differential or selectively permeable . In this way trying to maintain the shape of the cell membrane and chemical reactions in the cell in order to move on .
B. Sitplasma
Sitplasma is fluid and its dissolved substances that fill the space in the cell membrane and is limited by the cell . The cytoplasm is a colloidal system is very dynamic and constantly moving . Fluid that fills the organelles known as cytosol .
In the cytoplasm or cytosol too major organic compounds for life , gas ions , small molecules such as salts , fatty acids , amino acids , sugar nucleotides , vitamins , and protein and RNA were membetuk colloidal solution . The colloidal solution resulted in the cytoplasm constantly moving randomly , which is known as Brownian motion . This random motion is affected by the electrical charge of ions ( electrophoresis ) .
Colloidal solution can undergo phase changes from sol to gel phase and vice versa . Cytosol is also the venue for metabolism , such as glycolysis or the breakdown of glucose , protein synthesis , fatty acid synthesis , and others. Sharing process is done by a variety of organelles in the cytoplasm to form a suspension .
C. organelles
To carry out the various functions of life , the cell has various organelles , like the nucleus , mitochondria , ribosomes , lysosomes , plastids , endoplasmic reticulum , Golgi bodies , and micro entities .
1 . nuclei
The nucleus is the largest cell organelle that contains the genetic information in the form of DNA , and are round to oval cell type dependent . The nucleus is the organelle that is very vital for life , which controls all cell activities . Some important parts of the nucleus , namely :
The core membrane , nuclear membrane consists of two layers that serve as a protective wrapping as well as the core . Outer membrane has a direct relationship with the endoplasmic reticulum . At the core there is a membrane pores that allow the exchange of substances between the nucleus membrane to the cytoplasm . In eukaryotic organisms , unless the adult mammalian red blood cells and phloem cells , the nucleus is shielded by the nuclear membrane .
Nucleoplasm , nucleoplasm is a liquid gel core that is rich in ions , proteins , enzymes , nucleotides , and the threads of chromatin . Chromatin threads are shortened , thickened , and easily absorbs dyes called chromosomes . Stored in the chromosome DNA strands bound to basic proteins known as histones .
Nucleoli , this section is composed of a collection of genes that provide the code ribosomal RNA . As penkode ribosomal RNA , this structure serves to assemble constituent ribosomal subunits .
2 . endoplasmic reticulum
Endoplasmic reticulum membrane is a complex system that is composed to form irregular nets work ( reticulum ) , which is present in the cytoplasm of eukaryotic cells . These organelles in the cytoplasm acts as a channel that connects the nucleus .
Endoplasmic reticulum is divided into two , namely RE and RE smooth rough . RE rough has ribosomes on their surface that serves as the site of protein synthesis . While , RE smooth function as a lipid synthesis . In addition , they also play a role in the transport of chemical compounds necessary for cell metabolism .
3 . ribosomes
Ribosomes are small organelles inside the cell with a diameter of approximately 20nm . Ribosomes are free in the cytoplasm or attached to the membrane of RE as an ongoing process of protein synthesis . If the process of protein synthesis is not taking place in the form of ribosomal small and large subunits .
4 . centrioles
This organelle consists of a pair of tubular body ( cylinder ) and is an entity called the centrosome . Centrioles contain consisting of nine microtubule triplets , located near the nucleus . The centrioles play a role in the cell division process membentu spindle thread .
5 . Golgi bodies
These organelles form complex structures such as nets . The numbers stand out on the gland cells . Golgi apparatus serves to :
Lifting and chemically alters the materials contained therein .
Produce mucus , patchwork wax in plants , and secretions are sticky .
Sometimes for the transport of fat .
Secretion of proteins , glycoproteins , carbohydrates , and fats .
Forming lysosomes .
Forming digestive enzymes that have not been active ( zimogen , coenzyme , and others) .
In the Golgi apparatus , protein from RE tied to short-chain carbohydrates to form glycoproteins . Structure of the Golgi apparatus varied , ranging from the shape is not clear to form webs or nets . In plant cells , the Golgi apparatus is often called diktiosom .
6 . lysosomes
Lysosomes are organelles cells rather round -shaped pouch and is limited by a single membrane system . This organelle found in most eukaryotic cells , primarily in animal cells have phagocytic activity . Lysosomes contain many hydrolytic digestive enzymes , such as protease , nuclease , lipase , and phosphatase formed by RE rude . Further enzymes are delivered to the Golgi apparatus . Lysosome function to :
digest material taken endocytosis .
autofagi , namely the destruction of structures in the cell that are not desired .
exocytosis , the release of enzymes out of the cell .
autolysis , the self-destruction of cells by freeing all the contents of lysosomes in the cell .
7 . mitochondria
Mitochondria are cell organelles such as sausage -shaped , and its structure is very complex , present in all eukaryotic cells aerobic . This organelle is the venue for aerobic respiration in cells . Mitochondria are protected by a double membrane . Grooved inner membrane called cristae , serves to expand the surface .
8 . chloroplast
Chloroplasts are plastids that contain the green pigment , yellow , or red . Function as organizers of photosynthesis . In the chloroplasts of photosynthetic pigments are located in the membrane system and scattered throughout the base material called stroma . Role of photosynthetic pigments in higher plants is to absorb light energy and then convert it into chemical energy .
9 . Micro Agency ( peroxisome and Glioksisom )
Micro entity shrouded by a single membrane containing the enzymes catalase and oxidase . This organelle size of lysosomes and has two types , namely peroxisomes and glioksisom .
Peroxisome always associated with other organelles and contain many enzymes catalase and oxidase . In animals , confined peroxisomes in the cells of the liver and kidneys . While the plants are in various cell types . Peroxisomes play a role in the oxidation of the substrate , the metabolism of fat into carbohydrate , and purine changes in the cell .
Glioksisom present in plant cells . Its function is to oxidize fatty acids into sugars which is useful for plant growth .
Thanks for sharing the detailed information about various parts of a cell. Based on the features of cell membrane, our team developed antibody targeting membrane protein with MemProArt™ platform.
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