Permeable selective barers and Transport of Macromolecules

Permeable selective barers

Cell membranes prevent the exchange of material freely from one side to the other at the same time. The plasma membrane must guarantee the exchange of molecules between the inner and outer parts at the right time.

Molecular transport

The plasma membrane contains a molecular transport machine from one side to the other which prevents molecules with low concentrations from entering the regional cells that have a high concentration. This machine allows cells to accumulate certain molecules in a higher concentration compared to the outside.
Signal delivery

Plasma membranes play an important role in cell response to signals. The process is called signal delivery. Cell membranes have respors that combine with certain molecules (ligands). Each different cell has a different receptor, which is able to recognize and respond to ligands in different environments.

Intercellular interaction

Cell membranes mediate cell-to-cell interactions in multicellular organisms. Cell membranes allow cells to know each other, bond and exchange material and information
Mechanism of Transport through Cell Membranes

Small molecules and ions move across the plasma membrane in two directions like sugar, amino acids and other nutrients enter the cell, and waste metabolism products leave the cell. Cells absorb oxygen for cellular respiration and release dioxidal carbon. The cell also regulates the concentration of inorganic ions such as Na +, K +, Ca2 + and Ca- by reversing their direction from one direction to another across the plasma membrane.

Although the traffic through this membrane is dense the cell membrane is selectively permeable (the membrane can only be traversed by certain polar ions and molecules), semipermeable (easily passed by water molecules) and substances cannot cross the barrier arbitrarily. These cells can take a variety of small molecules and ions and reject the other besides that the substances move across the membrane at different rates.

Cell membranes have a function in the movement of ions or molecules from inside or outside the cell. According to Campbell, the central part of the hydrophobic membrane blocks the transport of polat ions and molecules which are both hydrophilic. The structure of lipid bilayers is the cause of permeable selective properties in membranes. The molecular or ionic movements that occur in cell membranes and other organelles are:

Diffusion

Simple diffusion
Ulustrasi proses difusi pada larutan
Illustration of the diffusion process in the solution
Diffusion is a spontaneous process in which molecules move from areas of high concentration to areas with low concentrations. Membranes are selectively permeable which affects the diffusion rate of several types of molecules. One type of molecule that diffuses freely through many types of membranes is water.

Diffusion depends on the random movement of a solute. Molecules can pass through the plasma membrane by a simple diffusion path that is very limited in number and for this reason the plasma membrane still has a barrier.

Micromolecules especially hydrophobic types can easily pass through the plasma membrane. The ability of cells to be able to sort hydrophilically with a small molecular weight (BM) of compounds that have a high BM is often caused by the presence of porous in the plasma membrane. There are two types of porous.

The first type that can penetrate integral proteins or between groups of transmembrane protein molecules. The second type of porus is called statistical porus that forms randomly on the plasma membrane and penetrates the lipid bilayer.

Facilitated Diffusion

The diffusion of a compound or molecule across the membrane always occurs from areas with high concentrations to areas with low concentrations, but diffusion does not always occur through lipid bilayers or an open channel.

A number of substances are known to diffuse by first binding to a mebran protein called facilitative transporter which facilitates the diffusion process. Binding of molecules or compounds in the facilitator's transportitives on one side will trigger a transformational change in the protein and cause the solute to diffuse into low concentrated areas.

Compounds that pass through the plasma membrane by diffusion are facilitated also do not require ATP involvement, as is simple diffusion. But the movement of compounds from outside to inside or vice versa is faster than simple diffusion.

This is caused by the presence of carrier proteins that accelerate transport. The carrier protein molecule after binding to the compound or molecule to be carried, immediately moves the compound / molecule from the outside in or vice versa.

Osmosis

Osmosis is the event of the transfer of water molecules (solvents) through a semipermeable membrane from a low concentrated solution to a high concentration solution. This osmosis event occurs in cells.

The event depends on the ratio of the concentration of the solution inside and outside the cell. If the concentration of the solution outside the cell is lower than the solution in the cell, it means the cell is in a hypotonic solution. The concentration of the solution outside the cell is higher than the solution in the cell, meaning the cell is in a hypertonic solution.

Active Transport

Active transport is transport that uses energy to excrete and insert ions and molecules through a selectively permeable cell membrane. Active transport is affected by electrical charges inside the cell and outside the cell. This electric charge is determined by sodium ions (Na +), potassium ions (K +), and chlorine ions (C1-).

The entry of Na + and K + ions is regulated by the sodium-potassium pump. The sodium-potassium pump is responsible for the Na + and K + double active transport from inside the cell out. ATP provides energy for transport. The pump secretes three Na + ions from inside the cell for every two K + ions that are inserted into the cell. In the transport protein, there are Na + and K + called binding sites.


Active transport stages that occur in the cell membrane

• Three sodium ions (Na +) are taken in cells and occupy the binding sites (where the bonds of ions or molecules occur in the membrane).
•  Energy is needed to change the shape of an integral protein in the membrane to open to the outside of the cell.
• The integral protein in the membrane opens outward from the cell, then releases sodium ions out of the cell.    Two potassium ions (K +) from outside the cell occupy the binding sites on integral proteins.
•  The integral protein in the membrane returns to its original shape, which is opening towards the cell.
• The potassium ion is released into the cell.

Transport of Macromolecules through the Plasma Membrane

Macromolecules such as proteins or polysaccharides cannot pass through transmembrane proteins that act as carriers. But the cell can still enter and remove the macromolecules.

The transport of macromolecules is very different from the transport of micromolecules. The mechanism of transporting macromolecules from the external environment into a vesicle is carried out through a fold or invagination of the plasma membrane. Macromolecule removal from the extracellular matrix can be divided into two categories, phagocytosis, namely the taking of solid maromolecules and pinocytosis of taking liquid material.

Phagocytosis

Phagocystosis ("cell eating") is a common solid material taken by certain types of cells to be carried to lysosomes.

Single-celled organisms such as Amoeba and Ciliata take food by capturing food particles or small organisms by covering it with plasma merman. The fold then fuses to form sutu vacuoles (phagosomes) which will separate from the plasma membrane. Phagosomes will then join with lysosomes to reach intracellular food.

In some high-level animals, phagocytosis is more of a protective mechanism than the way food is taken. Mammalia has a variety of phagocyte cells such as macrophages and neutrophils that are found in the blood and other tissues that will "eat" organisms, cells that have been damaged, red blood cells that have been old or debris.

Endocytosis

In endocytosis, cells enter very small macro molecules and matter by forming new vesicles from the plasma membrane. The steps are basically the opposite of exocytosis.

A small portion of the plasma membrane is buried deepest into a pocket. As soon as this bag gets deeper, the bag is pinched, forming a vesicle containing material that is already outside the cell. There are three types of endocytosis, namely phagocytosis (cellular feeding) pinositosi (cellular drinking) and endocytosis which is receptor-bound.

Endocytosis can generally be divided into two groups: bulk-phase endocytosis and receptor-mediated endocytosis. Bulk-phase endocytosis takes extracellular fluid without an introduction process by the plasma membrane surface. Bulk-phase endocytosis can be observed by providing certain ingredients in culture medium such as the horseradish peroxidase enzyme which cells will take in general. Receptor-mediated endocytosis is the taking of certain macromolecules (ligands) that will bind to receptors on the outer surface of the membrane.

Exocytosis

Cells secrete macro molecules by combining vesicles with a plasma membrane called exocytosis. The transforic vesicles that are released from the golgi apparatus are transferred by the cytoskeleton to the plasma membrane. When the vesicular membrane and plasma membrane meet, the second bilayer lipid molecule rearranges itself so that the two membranes join. The vesicles are then spilled from the cell.

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Structure and Function of membrans Cells

Cell membranes or plasma membranes are the boundaries that separate cells from other cells or from objects around them. The structure of the cell membrane consists of a thin layer about 8 nm thick.

1 nm = 0.000000001 M

The function of cell membranes is to control the traffic of substances that enter and exit the cell.
Like other biological membranes, the plasma membrane also has selective permeable properties. Permeable selective properties are the ability of the membrane to select some substances that can pass easily and other substances cannot pass through it.
Membranes limit a solution that has a different composition from the surrounding solution, but can still absorb nutrients and waste disposal.
The structure of the cell membrane consists of a phospholipid, hydrophilic, and hydrophobic layer. You can see the structural picture in the picture below:
The structure of the cell membrane consists of a phospholipid, hydrophilic, and hydrophobic layer
The ability of cells to differentiate a chemical is a fundamental ability that is needed for life, and the plasma membrane is a part of the cell that has this ability to be effective.

Also Read :  Teory of Cell

Function of cell membranes

The cell membrane functions as a semipermeable barrier that allows small molecules to enter the cell. The results of electron microscope observations on cell membranes indicate that the cell membrane is a lipid bilayer . (referred to as the fluid-mosaic model ).

The main constituent molecule is phospholipid , which consists of a polar ( hydrophilic ) head and two nonpolar ( hydrophobic ) heads. These phospholipids are composed of nonpolar parts forming a hydrophobic area flanked by the area of the membrane which is on the inside and outside of the membrane.

    Hydrophilic = likes of water
    Hydro phobic = expel water
    [ source ]

Structure of cell membranes

The structure of the cell membrane is composed of fat and protein in which each component is bound by a non-covalent bond. In addition to fat and protein, the structure of the cell membrane also consists of carbohydrates.

The ratio between fat and protein varies depending on the type of cellular membrane. For example between the plasma membrane and the endoplasmic reticulum. The types of prokaryotic and eukaryotic organisms also have different structural ratios. The mitochondrial membrane has a high protein / fat ratio compared to the plasma membrane in red blood cells.

Lipids on the membrane are composed of phospholipids (phosphate-compounded fats). Phospholipids are the most abundant lipids in most membranes. Phospholipids play a role in forming membranes in accordance with their molecular structure.

Phospholipid is an amphiphatic molecule which means that this molecule has both hydrophilic and hydrophobic regions.
Most membranes contain phosphate. Phosphate molecules are hydrophilic (can bind water) while fat molecules are hydrophobic (cannot bind water).
Another fat component is cholesterol wherein certain animals can reach 50% of the fat molecules contained in the plasma membrane. Cholesterol is not present as a large membrane of plant plasma and bacteria.
Lipids contained in the membrane can be extracted with chloroform, ether and benzene. By using thin layer chromatography and gas chromatography, the lipid composition of the cell membrane can be determined. Lipids that are always found are phospholipids, sphingolipids, glycolipids and sterols. Cholesterol is the most lipid that makes up the cell membrane.

Carbohydrate

Carbohydrates in the membrane act as constituents of cells and to differentiate the types of cells around them. Carbohydrates also play an important role as selector of cells that make up various tissues and organs in animal embryos.
Cell recognition is also the basis for rejection of foreign cells (rejection of transplanted or transplanted organs) by the immune system.

Carbohydrates in membranes are usually short branched chains composed of less than 15 sugar units, some of which bind covalently to lipids, forming a molecule called glycolipids. But most carbohydrates bind covalently to proteins, forming glycoproteins.

Protein

Protein membranes are composed of glycoproteins or proteins that are compounds with carbohydrates. Depending on the type of cell and certain organelles in the cell, the membrane has 12 to more than 50 different types of proteins. This protein is not randomly arranged but each location and orientation is arranged in a certain position on the lipid bilayer.

Proteins in the membrane are asymmetrical on the outside of the membrane and inside of the membrane, aka arranged in different positions. This position allows the outer membrane to interact with extracellular ligands such as hormones and growth factors, while the inside can interact with cytoplasmic molecules such as protein G or protein kinase. There are two main layers of protein membranes.

Integral protein

Integral proteins are proteins that mix into lipid bilayers. This protein can penetrate the membrane so that it has a domain on the extra cellular and cytoplasmic side of the membrane. Integral proteins are generally transmembrane proteins, with a hydrophobic area that extends throughout the interior of the hydrophobic membrane.

The hydrophobic area of integral proteins consists of one or more ranges of nonpolar amino acids, which usually coils into helix a on the hydrophilic end of this molecule is exposed to aqueous solubility on both sides of the membrane.

Peripheral protein

Peripheral protein is not found in lipid bilayers at all. All of them are found on the outside of the lipid bilayer, both on the extracellular and cytoplasmic adjoining surfaces and are related to the membrane through non-covalent bonds. This protein is a member that is loosely bonded to the surface of the membrane, often also in the integral part of the protein that is left exposed. Proteins in the membrane determine most of the specific functions of the membrane.

Lipid anchor protein

The cell structure consists of many parts such as carbohydrates, glycoproteins, proteins, cholesterol and others Lipid anchor proteins are found outside the lipid bilayer but bind covalently to the fat molecules found in lipid bilayers.

Plasma membrane protein has a very broad function, among others, as a protein carrier (carrier) compounds through cell membranes, recipients of hormonal signals and forward the signal to the cell itself or other cells. Plasma membrane protein also functions as a binding component of the cytoskeleton with extracellular compounds.

Outer surface proteins provide individual cell characteristics and protein types can change according to cell differentiation. Proteins in many cell membranes also function as enzymes, especially those found in the mitochondrial membrane, endoplasmic reticulum and chloroplasts. For example, plasma membrane phospholipid compounds are synthesized by enzymes found in the membrane of the endoplasmic reticulum.

Cell membrane proteins have the ability to move, so they can move. The displacement takes place laterally by diffusion. But not all pseudo proteins can move. Several types of integral proteins are retained in the membrane by woven protein molecules that are just below the inner surface of the plasma membrane. This webbing is related to the cytoskeletal or cell skeleton.

The physico-chemical structure of the cell membrane protein is less known, given that its shape varies greatly. Based on microscopic studies and freeze fracture techniques it is known that proteins in cell membranes are globular shaped.

Compartment

The plasma membrane divides the protoplasm into several compartments (spaces). Cell membranes wrap around the entire protoplasm. The membrane of the nucleus separates the nucleoplasm from the stoplasma.
In addition the plasma membrane divides the cytoplasm into several compartments called organelles. The presence of this limiting membrane is very important because it allows the activities of each compartment to take place without interference from other compatments but can still work together.

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Teory of Cell

Cell theory is an important material that we must understand in studying biology .
 As we know that the Cell is the smallest structural and functional unit that composes the body of a Living Being.
Who is the first person to find a cell? Who are the scientists who think about cell theory? What is the sound of the cell theory they put forward?

Everything will be discussed here.

Cell Pressure

Many scientists have researched and concluded that plants and animals are composed of cells. Starting from the 18th century to the beginning of the 19th century. However, cell theory at the time was still debated.

In 1838, the German botanist Matthias Jakob Schleiden stated that all plants consist of cells and all the functions of the plant body are basically cell activities.

He also stated the important role of the nucleus (which Robert Brown discovered in 1831) in cell activity and cell reproduction . Although he thinks that cells are formed from the nucleus.  In 1839, Theodor Schwann, who had discussed with Schleiden, realized that he had observed the nucleus of animal cells as Schleiden observed them in plants.

He stated that all parts of the animal's body are also composed of cells. According to him, all tissues in living things (organisms) are composed of cells. Then cell theory was introduced in more detail by Rudolf Virchow , a German scientist. At first he agreed with Schleiden regarding cell formation. Microscopic observations of various pathological processes led him to conclude the same thing that had been concluded by Robert Remak .  Robert Remak had previously observed red blood cells and embryos. The conclusion is that ' cells come from other cells through cell division ' .


In 1855, Virchow published a famous paper, omnis cellula e cellula (all cells derived from cells).

Robert Hooke

Robert Hooke is the first person to name a cell or can be called the first person to find a cell. The term cell was discovered by Robert Hooke after observing a dry cork incision.

Initially in 1665 a British scientist Robert Hooke examined the thin slices of cork through a microscope that he designed himself. The word cell comes from the Latin word cellula, which means space.
In 1835, before the cell theory was defined as the smallest organizational unit that composed living things. All functions of life are regulated and take place in cells. Because of this, the cell can function independently as long as all of its life needs are met.

Scheilden and Schwann

Cell Theory according to Scheilden and Schwann states that 'Cells are structural entities'

Scheiden and Schwan are scientific figures who are very instrumental in the world of microbiology, with cell theory is a structural unity (based on form). Scheilden observed cells in plants and Schwann observed cells in animals. The following are the results of his observations:

Animal Cells

1. Does not have a cell wall
2. Don't have plastids 
3. Having lysosomes 
4. Have centrosomes 
5. The accumulation of substances in the form of fat and glycogen 
6. Non-permanent form 
7. In certain animals have vacuoles, small size, little.

Plant Cells

1. Has a cell wall and cell membrane
2. Generally has plastids 
3. Do not have lysosomes 
4. Don't have centrosomes 
5. Substances in the form of starch 
6. Fixed shape 
7. Has a large vacuole, lots

ALso Read :  Communication between Cells

Max Schultze

Cell Theory according to Max Schelze reads ' Cells are functional units '

His name is very well known for his work on cell theory. By combining Felix Dujardin's theory of the concept of "sarcode" in animals with Hugo von Mohl with protoplasm in vegetables, he unites the two and the two things are included under the common name protoplasm, defining cells as nucleated masses of protoplasm with or without cell-wall ( Das Protoplasma der Rhizopoden und der Pflanzenzellen; ein Beiträg zur Theorie der Zelle , 1863).

Rudholf Virchow

Cell Theory According to Rudolf Virchow who said that 'All cells come from cells ( omne cellulae e cellula )'

Virchow was instrumental in many important discoveries. Although he and Theodor Schwann were not mentioned together, he was most widely known because of his theory of cells. He was the first to find leukemia cells.

Rudolf Virchow was the first person to accept and trace the work of Robert Remak who stated the origin of the cell was the division of the previous element. This theory was stated in the paper Omnis cellula e cellula (each cell came from the previous cell) which was published in 1858. This paper also denied the theory of living things from inanimate objects.

Thomas Huxley

Thomas Huxley stated that his cell theory which is called 'Cell is a physical unit of chemistry'.

Watson and Crick

Theory Cells deflect Watson and Crick are cells that are a unit of heredity

Robert Brown

The theory of cells according to Robert Brown is 'In the cell there is a cell nucleus (nucleus)'

Robert Brown is a Scottish botanist who made an important contribution to botany through the discovery of cell nuclei and cytoplasmic flow. The first observation of the Brown Movement is the initial research on pollination and fertilization in plants.

Brown was also one of the first to recognize the fundamental difference between the plants of gymnosperms and angiosperms, and did an early study of palinology. He also contributed a lot to the taxonomy of plants, including the classification of a number of plant families that are still accepted today and many genera and Australian plant species, the results of which are explored along with Matthew Flinders

Felix Dujardin

The theory of cells by Felix Dujardin is 'Inside every cell of living things there is a cytoplasm'

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Communication between Cells

Understanding Inter Cell Communication
Communication between cells is the interaction between one cell and another cell or between cells and their environment.
The purpose of this communication is so that every organ in our body can carry out its functions properly so as to maintain survival.
Humans can get information because they communicate with other people. Human communication is done by using various media such as sound, images or body movements.

Sounds, images or body movements are examples of information.
Information can come in various forms. In fact, there is also information whose shape changes from one form to another.
When we call for example. Our sound waves are converted into electrical signals so that they can flow through telephone cables. An important point of this process is when the message is changed from one form to another. This change process is called signal transduction.


Also Read :  Plant Cells and Organelles and Their Functions

So how can intercellular communication occur? What use? The answer can be found in the explanation below.

Signal Molecules (Ligands)

Plant cells and animal cells communicate using extracellular signal molecules called ligands. This communication aims to control cell metabolism, growth, tissue differentiation, protein synthesis and protein secretion and regulate the composition of extracellular fluid.

This signal molecule or ligand is synthesized (made) and secreted by the signal cell. One signal molecule only produces one specific response in the target cell that has a specific receptor (according to response).

In multicellular organisms, signal molecules can be hydrophilic or hydrophobic molecules. Both groups of molecules have different mechanisms in the process of working in cells.

Some hydrofibic signaling molecules such as steroids, retinoids and thyroxine can function both within cells and bind to intracellular receptors (between cells). There are 2 types of intracellular receptors, namely receptors found in the cytoplasm (Cytoplasmic Receptor) and in the cell nucleus (Nuclear Receptor).

Various hydrophilic small molecules such as (amino acids, lipids, and acetylcholine), peptides and proteins are used for cell-to-cell communication.

Signal molecules are steroid hormones (estradiol, progesterone, testosterone), vitamin D 3 and retinoic acid which can penetrate cell membranes and bind to intracellular specific receptors and form hormone receptor complexes.

Then it translocates into the cell nucleus and binds to DNA elements that are responsive to complex receptors. This process causes the activation of the target gene to synthesize certain proteins.

The way of communication between other cells is through receptors found on the surface of cell membranes (membrane receptors). In this case the ligand molecule works as a ligand that binds to complement molecules on the outer surface of the cell membrane.

This bond causes changes in the receptor component in the cell or induces a specific cellular response. This process is known as signal transduction.

One group of receptors on the membrane surface that activates protein G is known as G proteincoupled receptors (GPCRs). GPCRs are found in all eukaryotic cells, from yeast (yeast / fungus) to humans.


Humans can code several thousand GCPR. This includes receptors in the eye, touchers, flavorings, some neurotransmitter receptors and hormone receptors that control the metabolism of carbohydrates and amino acids in general.

Molecules of Signals and Receptors of Membrane

Communication using extracellular signals usually involves the following steps:

1. Synthesis
2. Release of signal molecules by signal cells 
3. Transport the signal to the target cell 
4. The signal molecule binds to the receptor protein to activate it 
5. Initiation of one or more transduction signal pathways that have been activated by receptors 
6. Specific changes in cellular function, metabolism or development and 
7. Signal release so that often causes the cellular response to cease.

Most receptors are activated by bonding molecules with membranes (eg hormones, growth factors, neurotransmitters and pheromones). There are several ways of cell communication that use membrane receptors namely juktacrin, autocrine, paracrine and endocrine.

Signaling juktakrin

Juktakrin signaling is the communication of two cells adjacent to forming a pore that connects the two cells so that the smallest ions and molecules can pass through the pores that form.

Autocrine signaling

Signaling cell autocrine or cells responds to molecules that are secreted by themselves. This signal is also found in tumor cells that are over-secreted by growth factors to induce uncontrolled cell proliferation. This causes the formation of tumors that can suppress the surrounding tissues or organs.

Paracrine sign

Paracrine signaling is a short distance communication between cells. The signal cell secretes its target signal molecule in cells adjacent to the signal cell.

For example epinephrine is a neutotransmitter released by one nerve cell to another nerve cell or nerve cell to effector in skeletal muscle (stimulates or inhibits contraction). Then it can bind to membrane receptors in the surrounding target cells and induce changes in the target cell.

Endocrine Signaling

Endocrine signaling is an example of communication between long-distance cells because the signal cell is located in a location that is relatively far from the target cell. In this signal the signal molecule is a hormone. The signal molecule can get to the target cell because it is transforced through blood or other extracellular fluid.

Endocrine signaling, for example, occurs in the female reproductive cycle. The hormones involved can be either peptides or steroids. Peptide hormones such as follicle stimulating hormone (FSH), Lutenizing Hormone (LH) and Gonadotropins. While steroid hormones such as estrogen and progesterone.
Endocrine signaling mechanism in the female reproductive cycle

Intraselular Transduction Signals

Transduction signals are the process of converting a signal molecular bond to the target cell receptor to produce a biological response. In this case there are second messengers that work as signal transduction agents. This second messenger can carry signals from several receptors.

In signal transduction of bonds with ligands (first messenger) on several membrane receptors in a short time can increase or decrease the concentration of small molecules which are second messengers. Some of the following molecules are cAMP (cyclic AMP), cGMP, DAG (1,2 diacylglycerol) and inositol triphosphate (IP3) which act as Second messenger.
PROTEIN G (GPCR) RECEPTOR COMMITMENT THAT ACTIVATES OR LIMITS ADENIL CYCASE

There are numerous membrane receptors associated with G protein transduction signals. All GPCR consists of seven segments where terminal N is outside the membrane and terminal C is contained in the cytosol.

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Plant Cells and Organelles and Their Functions

Typical organelles Plant cells are cell walls and plastids. The cell wall functions for protection and plastide (chlorophyll) functions for photosynthesis . The following is a complete discussion. This biological article will explain plant cells, plant cell structures, plant cell organelles, the function of their organelles , and plant cell components.

Plant Cells

Cells are the smallest unit of life. Every living thing is composed of many cells ( multicellular ), but some are only composed of one cell ( unicellular ). Plants include multicellular living things. Plant cells are also included in eukaryotic organisms, not prokaryotic. Eukaryotic organisms have a true nucleus that is bound to the membrane (nucleus membrane). Eu means true and karyon means core. The cell size is relatively large (10-100 μm) and has membrane-bound organelles such as RE, golgi bodies, mitochondria, and lysosomes. Eukaryotic cells also have membrane-bound organelles such as ribosomes, microtubules, centrioles and cytoskeletons.

Examples of eukaryotic organisms are animals and plants

Other with prokaryotic organisms ...

Prokaryotic organisms are living things whose cell nucleus has no membranes or membranes. Pro means primitive and karyon means core. The size is small (0.5 - 1 μm) and has no organelles with an endomembrane system (nucleus, mitochondria, plastids). Examples of prokaryotic organisms are in the kingdom monera (bacteria and blue algae).

Besides being included in eukaryotic organisms, plants also include autototrophic organisms.

Autotrophs are organisms that are able to convert inorganic substances into organic substances. We often call it an organism that is able to make its own food.

Plants include autotrophic organisms because they have chlorophyll which functions to carry out photosynthesis. Chlorophyll is a leaf green substance produced by chloroplasts organelles.

Besides chloroplasts, plant cells also have other organelles. There are organelles that are only found in plant cells and some are found in other cells.

Typical Structure of Plant Cells

Plant cells are typical structures that distinguish them from other cells, especially animal cells. Anyway, we've discussed the differences in animal cells and plant cells in previous biology articles.

Read: Differences in animal cells and plant cells

The typical structure of plant cells is as follows:

1. The vacuole, in fact other cells also have vacuoles, but are very rare and even if there is a very small size.
2. Plastids, one type of plastid that you know is chloroplasts. In addition to chloroplasts, there are also other types of plastide that will be below below. 
3. Cell wall, this is the structure that makes the body of the plant stiff.

Plant cell organelles and their function

Here are the organelles in plant cells and their functions:

1. Nucleus (Core Cell)

The nucleus is the core organelle of a cell. This organelle consists of four parts, namely the Core membrane (Karioteka), nucleoplasm (Kariolimfa), chromatin or chromosome (genetic material) and nucleoli (core child).  The function of the cell nucleus is to regulate all cell activity because it contains genetic material (DNA and RNA) which functions to print proteins.  Of course you know that protein functions as our body's builders.

2. Endoplasmic reticulum (RE)
The endoplasmic reticulum is an organelle consisting of two layers of membrane, cysterna and tube. If we look at the cell image, this RE is like a sheet attached to the cell nucleus.
The RE function is as follows:

1. Intracellular transport of material to be secreted
2. The means of transporting substances in the cell itself 
3. Involved in the formation of vacuoles 
4. Form a membrane in the golgi body

Anyway, RE is divided into two types, namely smooth RE and rough RE. The smooth RE is not attached to the ribosome. While the rough RE is attached to a ribosome so that it looks like it has a rough surface.

3. Ribosome

Ribosomes are round organelles, very small in size compared to other organelles. Ribosome structure consists of two parts, namely large and small parts. The large part is called a large subunit and the small part is called the small subunit .  Ribosomes are composed of proteins and RNA, some are attached along the RE and some are solitary or freely dispersed inside the cell.  The function of ribosomes is as a place for protein synthesis

4. Mitochondria

The mitochondrial structure is oval, has two layers of membrane (double membrane), the inner layer is curved and is called Krista. Inside the mitochondria there is also DNA.

The function of mitochondria is as a cellular respiration center that produces a lot of ATP (energy).

5. Golgi Body (Diktiosom)

The Golgi body or Golgi apparatus consists of a group of cysterna that is flattened and arranged in parallel.  The function of the Golgi body is related to the function of cell excretion.

6. Plastida

Plastids are divided into three types, namely:

• Leukoplas, which is a white plastide that serves as a food store. Leukoplas consists of:

1. Amiloplas (to save starch) 
2. Elaioplas (Lipidoplas) (for storing fat / oil) 
3. Proteoplas (to store protein) 

• Chloroplasts, which are green plastids. This plastide functions to produce chlorophyll and as a place for photosynthesis to take place
• Kromoplas, which is a plastide containing pigments. Kromoplas consists of:

1. Carotene (yellow)
2. Phikodanin (blue)
3. Fikosantin (yellow) 
4. Phytoerythrin (red)

7. vacuole

The vacuole is a sac surrounded by a membrane that contains fluid / water. Membrane or membrane dividing between vacuoles and cytoplasm is called tonoplas.

The function of vacuoles is as follows:

1. Water storage, food reserves, oils, enzymes, pigments, toxic compounds and metabolic byproducts.
2. Helps maintain turgor pressure in cells. 
3. Vacuole has an important role as a reservoir for secondary products in the form of liquid, so it is also called 'cell fluid'. 
4. Some experts say that vacuoles are not organelles (but are nonprotlasmic components). 
5. In young / meristematic cells, vacuoles are usually small and large. 
6. Whereas in adult vacuole cells are large. 
7. Plants do not have an excretory system like animals, therefore vacuoles function to store metabolic waste. 
8. The place for the destruction of certain compounds by hydrolysis enzymes. 
9. The vacuole with the vesicles contributes to the storage of material in the cell (the size of the vacuole is greater than the vesicle).

8. Peroxisomes

Is a special organelle equipped with a single membrane. These organelles produce oxidative enzymes that are used in the breakdown of metabolism.

The function of peroxisomes is to help the chloroplast when conducting photorespiration and as a breaker with fat into sugar.

Contains an enzyme that transfers hydrogen from various substrates to oxygen, which produces hydrogen peroxide as a by-product.

Plant cell components

Plant cell components consist of 2 main parts, namely the cell wall and protoplasts.

The cell wall is divided into three parts, namely the primary wall, secondary wall and middle lamela.

While protoplasts consist of protoplasm and non-protoplasm. Protoplasm includes cytoplasm (cell fluid), cell nucleus (nucleus), and organelles.

Parts of protoplasts that belong to the non-protoplasmic category are vacuoles and ergastic substances.  Such is the discussion of plant cell organelles, their functions and their components.

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