what is ROTARY
回答 (2)
2007-10-25 2:08 am
✔ 最佳答案
rotary
標示解釋
圖片參考：http://hk.yimg.com/i/dic/spacer.gif
釋義
變化形
圖片參考：http://hk.l.yimg.com/hk2.yimg.com/i/dic/dreye02.gif
KK: [
圖片參考：http://hk.yimg.com/i/dic/034.gif
]
DJ: [
圖片參考：http://hk.yimg.com/i/dic/033.gif
]
a.[Z]
1. 旋轉的;輪轉的;轉動的
the rotary movement of the blades
刀片的旋轉運動
2. (人員)輪流的,輪換的
3. (機械等)有旋轉部件的;旋轉式的
n.[C]
1. 旋轉式機器;轉缸式發動機
2. (大寫)扶輪社
3. 【交】【美】環形交叉口,環形交叉樞紐
"rotary"
相關搜尋: 網頁 | 知識
2007-10-25 2:12 am
Bacterial flagellum is a hollow tube 20 nanometers thick
there is noway a light and phase contrast microscope and view it in view of the resolution
Examples of bacterial flagaella arrangement schemes. A-Monotrichous; B-Lophotrichous; C-Amphitrichous; D-Peritrichous;The filament is composed of the protein flagellin and is a hollow tube 20 nanometers thick. It is helical, and has a sharp bend just outside the outer membrane called the "hook&q uot; which allows the helix to point directly away from the cell. A shaft runs between the hook and the basal body, passing through protein rings in the cell's membranes that act as bearings. Gram-positive organisms have 2 basal body rings, one in the peptidoglycan layer and one in the plasma membrane. Gram-negative organisms have 4 rings: L ring associates with the lipopolysaccharides, P ring associates with peptidoglycan layer, M ring is imbedded in the plasma membrane, and the S ring is directly attached to the plasma membrane. The filament ends with a capping protein. The bacterial flagellum is driven by a rotary engine composed of protein, located at the flagellum's anchor point on the inner cell membrane. The engine is powered by proton motive force, i.e., by the flow of protons (i.e., hydrogen ions) across the bacterial cell membrane due to a concentration gradient set up by the cell's metabolism (in Vibrio species the motor is a sodium ion pump, rather than a proton pump). The rotor transports protons across the membrane, and is turned in the process. The rotor by itself can operate at 6,000 to 17,000 rpm, but with a filament attached usually only reaches 200 to 1000 rpm.
The components of the flagellum are capable of self-assembly in which the component proteins associate spontaneously without the aid of enzymes or other factors. Both the basal body and the filament have a hollow core, through which the component proteins of the flagellum are able to move into their respective positions. The filament grows at its tip rather than at the base. The basal body has many traits in common with some types of secretory pore which have a hollow rod-like "plug&q uot; in their centers extending out through the plasma membrane, and it is thought that bacterial flagella may have evolved from such pores.
Different species of bacteria have different numbers and arrangements of flagella. Monotrichous bacteria have a single flagellum. Lophotrichous bacteria have multiple flagella located at the same spot on the bacteria's surface which act in concert to drive the bacteria in a single direction. Amphitrichous bacteria have a single flagellum each on two opposite ends (only one end's flagellum operates at a time, allowing the bacteria to reverse course rapidly by switching which flagellum is active). Peritrichous bacteria have flagella projecting in all directions.
Some species of bacteria (those of Spirochete body form) have a specialized type of flagellum called axial filament that is located in the periplasmic space, the rotation of which causes the entire bacterium to corkscrew through its usually viscous medium.
Anticlockwise rotation of monotrichous polar flagella thrusts the cell forward with the flagellum trailing behind. Periodically the direction of rotation is briefly reversed, causing what is known as a "tumble& ;quot;, and results in reorientation of the cell. The direction at the end of the tumble state is random. The length of the run state is extended when the bacteria moves through a favorable gradient.
rotary
標示解釋
圖片參考：http://hk.yimg.com/i/dic/spacer.gif
釋義
變化形
圖片參考：http://hk.l.yimg.com/hk2.yimg.com/i/dic/dreye02.gif
KK: [
圖片參考：http://hk.yimg.com/i/dic/034.gif
]
DJ: [
圖片參考：http://hk.yimg.com/i/dic/033.gif
]
a.[Z]
1. 旋轉的;輪轉的;轉動的
the rotary movement of the blades
刀片的旋轉運動
2. (人員)輪流的,輪換的
3. (機械等)有旋轉部件的;旋轉式的
n.[C]
1. 旋轉式機器;轉缸式發動機
2. (大寫)扶輪社
3. 【交】【美】環形交叉口,環形交叉樞紐
"rotary"
相關搜尋: 網頁 | 知識
there is noway a light and phase contrast microscope and view it in view of the resolution
Examples of bacterial flagaella arrangement schemes. A-Monotrichous; B-Lophotrichous; C-Amphitrichous; D-Peritrichous;The filament is composed of the protein flagellin and is a hollow tube 20 nanometers thick. It is helical, and has a sharp bend just outside the outer membrane called the "hook&q uot; which allows the helix to point directly away from the cell. A shaft runs between the hook and the basal body, passing through protein rings in the cell's membranes that act as bearings. Gram-positive organisms have 2 basal body rings, one in the peptidoglycan layer and one in the plasma membrane. Gram-negative organisms have 4 rings: L ring associates with the lipopolysaccharides, P ring associates with peptidoglycan layer, M ring is imbedded in the plasma membrane, and the S ring is directly attached to the plasma membrane. The filament ends with a capping protein. The bacterial flagellum is driven by a rotary engine composed of protein, located at the flagellum's anchor point on the inner cell membrane. The engine is powered by proton motive force, i.e., by the flow of protons (i.e., hydrogen ions) across the bacterial cell membrane due to a concentration gradient set up by the cell's metabolism (in Vibrio species the motor is a sodium ion pump, rather than a proton pump). The rotor transports protons across the membrane, and is turned in the process. The rotor by itself can operate at 6,000 to 17,000 rpm, but with a filament attached usually only reaches 200 to 1000 rpm.
The components of the flagellum are capable of self-assembly in which the component proteins associate spontaneously without the aid of enzymes or other factors. Both the basal body and the filament have a hollow core, through which the component proteins of the flagellum are able to move into their respective positions. The filament grows at its tip rather than at the base. The basal body has many traits in common with some types of secretory pore which have a hollow rod-like "plug&q uot; in their centers extending out through the plasma membrane, and it is thought that bacterial flagella may have evolved from such pores.
Different species of bacteria have different numbers and arrangements of flagella. Monotrichous bacteria have a single flagellum. Lophotrichous bacteria have multiple flagella located at the same spot on the bacteria's surface which act in concert to drive the bacteria in a single direction. Amphitrichous bacteria have a single flagellum each on two opposite ends (only one end's flagellum operates at a time, allowing the bacteria to reverse course rapidly by switching which flagellum is active). Peritrichous bacteria have flagella projecting in all directions.
Some species of bacteria (those of Spirochete body form) have a specialized type of flagellum called axial filament that is located in the periplasmic space, the rotation of which causes the entire bacterium to corkscrew through its usually viscous medium.
Anticlockwise rotation of monotrichous polar flagella thrusts the cell forward with the flagellum trailing behind. Periodically the direction of rotation is briefly reversed, causing what is known as a "tumble& ;quot;, and results in reorientation of the cell. The direction at the end of the tumble state is random. The length of the run state is extended when the bacteria moves through a favorable gradient.
rotary
標示解釋
圖片參考：http://hk.yimg.com/i/dic/spacer.gif
釋義
變化形
圖片參考：http://hk.l.yimg.com/hk2.yimg.com/i/dic/dreye02.gif
KK: [
圖片參考：http://hk.yimg.com/i/dic/034.gif
]
DJ: [
圖片參考：http://hk.yimg.com/i/dic/033.gif
]
a.[Z]
1. 旋轉的;輪轉的;轉動的
the rotary movement of the blades
刀片的旋轉運動
2. (人員)輪流的,輪換的
3. (機械等)有旋轉部件的;旋轉式的
n.[C]
1. 旋轉式機器;轉缸式發動機
2. (大寫)扶輪社
3. 【交】【美】環形交叉口,環形交叉樞紐
"rotary"
相關搜尋: 網頁 | 知識
參考: By me.
收錄日期: 2021-04-23 22:14:06
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071024000051KK02272