The Smallest Unit Cell As Matter of Life

Intellectual greetings. Well this time I post material to grade 10 high school biology. The first chapter is the material of the cell as the smallest unit of life. For more details, please understand the following explanation:
      If at first glance under the microscope, it appears that the cells form a rigid and as an inanimate object. But it turns out upon further investigation, within the cell occurs all the activities, in fact all of our daily activities that occur at the cellular level. This can be illustrated by our daily activities, for example, when we do activities reading books. What are cells that work when we do these activities? The cells of the body that works among others muscle cells. With the muscle cells, then we can hold the hand book. In addition, the rods and cones eye shadow also works receive texts or images. Afterwards, the brain cells would translate to produce a sense. Based on this description we can know that the cell is alive and cooperate with each other to perform the functions of life. These facts indicate that the human body is composed of a collection of cells. Cells are grouped to form a network, and then jaringanjaringan will arrange organ. Organs have a variety of shapes and functions. These organs are related to each other to form a system. This organ system that will form a new organism.
Well Did you know the history of the cell? The answer:

1. Galileo Galilei
In the early 17th century Galilei who is not a biologist in fact the first recorded observations of biology through the microscope by means of two lenses, he described the thin structure of insect eyes in the form of geometric patterns.
2. Robert Hooke
In 1665 Robert Hooke observe incision Quercus Suber cork stems of plants, he found an empty space bounded thick wall called cellulae which means the cells.
3. Jacob Schleiden (1804-1881) and Theodere Schwan (1880-1882)
The cell is the unity / structural unit of living things. This theory stated that at the conclusion observations:
Each cell consists of a living creature. The cell is the smallest structural unit of living things
That single-celled organisms (Monosel) and there were multicellular (multicellular).
Cell as a functional unit of living things.
4. Johannes Purkinje (1825-1895),
In the cell there is a component that is called life Prortoplasma
Felix Durjadin (1801-1860), Thomas Huxley (1825-1895) and Max Schultze (1825-1874). Which concluded that the protoplasm is the venue for the chemical reactions of life.
5. Rudolph Virchov (1821-1902)
Cell as a unit growth of living things found Omnis cellula ex cellulae (all cells derived from cells previously).
Cell as the unit of heredity of living beings. Progress of science and technology to encourage scientists to determine the structure of cell function more in the discovery of the structure of chromosomes and genes as well as strengthen its argument that a cell is a unit of heredity of living beings.

Cell Structure and Function
A cell has three main parts: the cell membrane (plasma membrane), cytoplasm and cell organelles. Differentiated cell structure of prokaryotic and eukaryotic cells.
Prokaryotic cells have no nuclear membrane, the membrane inside (endo membrane), mitochondria and chloroplasts. As for the parts of the prokaryotic cells (eg: bacteria and cyanobacteria) is a cell wall, composed of peptidoglycan, lipids and proteins. Plasma membranes, composed of lipoprotein that is selectively permeable cytoplasm, which is composed of water, proteins, lipids, minerals and enzymes that help the metabolic process both anabolism process (preparation) and catabolism (decomposition) substances. Mesosom on the wall mesosom contained respiratory enzymes that function in the oxidation reaction to produce energy such as mitochondria. Ribosome; as a protein synthesis. DNA is the genetic material that serves as a decrease in offspring nature (heredity).
Characteristic of this cell has a nucleus membrane, eukaryotic cells have a structure

A. The cell membrane (plasma membrane)
    Cell membrane in the form of a thin membrane, called plasmalema. The membrane between 5-10 nm thick. When observed with a light microscope is not obvious, but its existence can be proven at the time the cells undergo plasmolysis S. Singer and E.Nicolson (1972) present a theory of the cell membrane. This theory is called the theory of fluid mosaic membrane, which explains that the cell membrane is composed of proteins that are arranged like a mosaic (spread) and each inserted between two layers of phospholipids. The cell membrane is the outermost part of cells and arranged berlapislapis. The building blocks of cell membranes are lipoprotein which is a combination of fat and protein. The cell membrane contains approximately 50% lipids and 50% protein. Lipids that make up cell membranes composed of phospholipids and sterols. Phospholipids have a symmetrical shape and length. One end of phospholipids are soluble in water (hydrophilic), which is called the polar end. Part sterols are insoluble in water (hydrophobic) called nonpolar end. Phospholipids are composed of two layers. In this case the protein can be divided into 2 as follows.
a. Extrinsic Protein (Peripheral)
This protein is located sticking between two layers of phospholipids. Protein extrinsic join the outer surface of the membrane is hydrophilic and is readily soluble in water.

b. Intrinsic Proteins (Integral)
This protein is located sinking in between two layers of phospholipids. Protein intrinsic joined in and hydrophobic membrane that is insoluble in water. Constituent of cell membranes in the form of carbohydrates bind to a protein molecule that is hydrophilic so called glycoproteins. The carbohydrates that bind to lipids that are hirofilik called glikopolid. The nature of the cell membrane is selectively permeable means is impassable by water and certain substances dissolved in it. The cell membrane has the function, among others:

*. as protectors of cells,

*. controlling the exchange of substances, and

*. a chemical reaction.
To support this function, the cell membrane has the ability to identify the substance. A substance needed to be allowed to pass, while the substances are not used in the form of waste will be disposed of. There are also certain substances issued for export to other cells. The entry of substances from the outside through the cell membrane, namely through the events of passive transport and active transport.

b. Cytoplasm
Is the material that fills between the nucleus and the plasma membrane. Cytoplasmic matrix called the cytosol that has fisikawi properties, among others: to change phase from sol to gel or otherwise, Tyndal effect, Brownian motion, the motion Siklosis etc.

c. Cytoskeleton
Also called the cell framework that consists of three kinds of fibers, namely:
Microfilaments: There are 2 kinds of proteins are actin and myosin are abundant in muscle cells.
Microtubules: Is a tube-shaped protein chains that spiral. This microtubule function: As the skeleton of cells to maintain cell shape. Help direct the movement of chromosomes when cells divide because these microtubules can be centrioles and spindle threads.

1. The intermediate filaments
Intermediate filaments: composed of protein fibers are small (8-10 mm) between the size of the micro-filament and mikrotubulus.Nukleus, the core of these cells play a role in "Control" activities cells. The constituent parts of the nucleus that is important is:
The nucleus membrane (the lining of the heart) Consisting of two layers of membrane (bilaminair), each of which is a bilayer.
Nucleoplasm is a liquid nucleus containing chromatin, granules and nucleoprotein. At the time the cell divides these chromatin proteins thread forming chromosomes
Nucleoli (the child nucleus) formed during the transcription process. If this process is complete the child nucleus shrink or disappear.
The endoplasmic reticulum is an organelle composed by a mesh-like membrane winding - winding (reticular) and its location centered in the cytoplasm (endoplasmic) then called the endoplasmic reticulum (ER). There are 2 kinds of RE namely:
a. Rough endoplasmic reticulum (Granulair) In rough call karenapada channel RE sticking fine granules (granules) dariRibosom.
b. Smooth endoplasmic reticulum (Non Granulair) because padasaluran RE no grain ribosome. It is the smallest organelles ribosomes in the cytoplasm, to function in protein synthesis.

 There Golgi complex in animal cells, the plant cells called diktisom. This is important in cell secretion. Therefore, complex / Golgi bodies is called organelles also referred to as the Secretary. Another function of the Golgi complex is formed acrosome sperm and egg cells and lysosomes. Golgi apparatus consists of parts Sakula (sisternal), vesicles (secretory vesicles) and Vakula (Micro vesicles)

Lysosomes lysosomes (Lyso: break, Soma: body) is a small pouch containing membrane enzyme called Lysozyme hodrolitik. This enzyme is produced by Ribosomes are then wrapped by the ER membrane and released into the cytoplasm with Lisosoma name. Lysosomes are organelles cell membrane-bound form of bags containing hydrolytic enzymes that are useful for controlling the intracellular digestion in various circumstances. Lysosomes was found in 1950 by Christian de Duve and is found in all eukaryotic cells. In it, this organelle has 40 kinds of acid hydrolytic enzymes such as protease, nuclease, glycosidase, lipase, phospholipase, phosphatase, or sulfatase. All of these enzymes is active at pH 5. The main function of lysosomes is endocytosis, phagocytosis, and autophagy.

- Endocytosis is influx from outside the cell macromolecules into cells through endocytosis mechanism, which then these materials will be brought to the small and irregular vesicles, called the early endosome. Some materials are sorted and some are reused (discharged into the cytoplasm), which was not taken into endosome further. Further in the endosome, the material is first met with hydrolytic enzymes. In the early endosome, pH about 6. Lower pH (5) in the endosome maturation and further resulting form the lysosomes.

- The process of autophagy is used for the disposal and degradation of parts of its own cells, like organelles that no longer function. Initially, part of the rough endoplasmic reticulum surrounds organelles and form autofagosom. After that, autofagosom fuse with hydrolytic enzymes of the trans Golgi and develop into lysosomes (or endosome-up). This process is useful in liver cells, the transformation of tadpoles into frogs, and human embryos.

- Phagocytosis is the process of entering large-sized particles and microorganisms such as bacteria and viruses into the cell. First, the membrane will wrap the particles or microorganisms and forming phagosome. Then, the phagosome will fuse with hydrolytic enzymes of the trans Golgi and develop into lysosomes (endosome-up).

l. Micro entities bodies sheathed in a single membrane, which contains the enzyme catalase. There are two types of micro entities, namely peroxisomes and glioksisom.

There peroxisomes in animal cells, functions and leaves of plants tinggiTerdapat level in plant cells, play a role in the metabolism of fatty acids.

In the resulting substrate oxidation of hydrogen peroxide (H2O2), which is toxic, with the help of enzymes catalase (produced by this organelle) will be broken down into H2O and O2 neutral to the cell.
a. Mitochondria Elliptical double walled, the inner wall forming protrusions called Krista. Krista structure can extend the surface so that the oxidation process more effective. Mitochondria is only found in eukaryotic cells are aerobic. Related functions as cellular respiration mitochondria that produce energy, often called the power house of the cell.

Differences Cells Plant and Animal Cells

1. Animal Cells:

* Does not have a cell wall

* Does not have a grain plastids

* Shape is not fixed because it has a cell membrane that situation is not rigid

* Relatively large number of mitochondria

* Vakuolanya much with the relatively small size

* Centrosome and centrioles apparent

2. Plant Cells

* Have a cell wall

* Has grains of plastids

* Fixed form because it has a cell wall made of cellulosa

* The number of mitochondria relatively little because its function is assisted by grain plastids

* Vacuole little but large in size

* Centrosome and sentriolnya unclear

Plant Cells

Plant cell organelles that are not found in animal cells is:

Cell wall. Plant cell wall consists of several layers, from outside to inside is the plasma membrane.

Secondary wall, found in adult tissue cells and form a cell wall is already tetap.Bhanpenyusun terdeiri of lignin, cellulose or hemicellulose.

The primary wall, ditemuksn PSDS msih meristematis arrives cells composed of cellulose substances.

Middle lamella composed of compounds protopektin:

The cell wall is formed by Diktiosom, means the formation of a new layer there are two (2) kinds
Apposition, a new layer placed over lama.bIntussuscepsi layer, a new layer is long diantaralapisan.,
Two cells connected by plasmodesma, namely benangplasma that fill sel.Noktah node that is part of the cell wall are not experiencing penebalann cell wall thickening of substance lignin (wood substance) in the process lignifikasi

2. Also called cavity cell vacuole is an organelle that contains fluid encased by a membrane tonoplas. In plant cells growing vacuole as a result of growth of the cells. This vacuole can serve as:

Metabolic waste dump

For example: Ca Oksolat, tannin, latex and alkaloids

A place to store food substances

For example: starch flour and sugar

Storing pigment

For example: anthocyanin

Storing essential oils

This oil is classified as etheric oils (volatile) eg eucalyptus oil, papermint and fragrance in flowers {Jasmine, Rosein, etc.}

Plastids is an organelle that is only found in plants, there are 3 kinds plastisida:


Is a colorless plastids (white) serves to store food, for example: amiloplas (starch), elailoplas (fat) and proteoplas (protein).

Is a colorless plastids, because they contain non-photosynthetic pigments, for example: xantofil carotene, fukosantin, fikoeritrin, phycocyanin and antosian.

Present in the eukaryotic cell organelles autotrof is encased by two (2) membranes, the outer part to regulate the entry and exit of substances being part of the wrapping matrices is called stroma. Membranes in sheet form that didebuttilakoid. Thylakoid at certain places piled-tunpuk called grana contain chlorophyll.

Based on the absorption wavelength, chlorophyll distinguished by:

Chlorophyll a (C77 H72 N4 O5 Mg) absorbs blue-green color.

Chlorophyll b (C55 H70 N4 O5 Mg) absorbs green color yellow

C chlorophyll absorb green-brown

Chlorophyll d absorbs green color red

Animal Cells
Animal cells do not have the plastid and the cell walls so that the shape is not fixed, vacuole only found in protozoa, namely:
Contractile vacuole which serves as osmoregulator (keep the osmotic pressure of the cytoplasm)
Non-contractile vacuole food vacuole {}, to digest food. This organelle formed by invagination (arms into) the cell membrane by the organism at a time perform phagocytosis and pinosinotis

Organelle found in animal cells, not present in plant cells are:
Only the lower plant cells that have this organelle. In the centrosome there are two (2) pieces of centrioles that play a role in cell division which became the polar division. Centrioles is composed of microtubules

Transport Mechanism In Cells
In metabolism, both anabolism and catabolism {} cells need to insert or remove substances from outside and inside the cell. Didnding transport of these substances to penetrate the cell membrane and can be done by diffusion, Osmose and transort active.

Is the transfer agent of high concentration to the low concentration

Is a displacement of the solvent from the solution of low concentration towards the solution of high concentration through a semi-permeable membrane.

Active Transort
Is a displacement of the solvent from a low concentration to the high concentration through a selectively permeable membrane.

Because against the concentration gradient then in need of energy from ATP decomposition. Diffusion and transport Osmose said passive because it does not need energy because dye molecules movement direction of the concentration gradient. In plant cells in addition to three (3) above methods still one way is imbibition. Imbibition is water intrusion events into the space between cells. For example: the entry of water at the time the seeds germinate

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