wt is the meaning of substrate?

Well.... in biochemistry.... substrate is a molecule upon which an enzyme acts. In Enzymes catalyze chemical reactions involving the substrate(s). The substrate binds with the enzyme's active site, and an enzyme-substrate-complex is formed. The substrate is broken down into a product and is released from the active site. The active site is now free to accept another substrate molecule.

An example of a substrate would be milk and the enzyme added would be rennin which causes milk to set. Another example would be the reaction of catalase in the decomposition of hydrogen peroxide which is:

2 H2O2 → 2 H2O + O2.
A general equation is as follows:

E + S = ES → EP = E + P

where E = enzyme, S = substrate(s), P = product(s) Note that only the middle step is irreversible.

The reaction follows Michaelis-Menten kinetics.

Well... for reactant in chemistry.... it means the molecule that react with in another molecule to form a chemical compound. This process might require the use of catalyist and in a right environment.

Overall... basically substrate is where an enzyme binds and to form a reaction which might involve a reactant. Reactant means the molecule that is require to form a product... if you still don't understand, email me and I will look at my biochemistry book again.... okie???

底物為參與生化反應的物質，可為化學元素、分子或化合物，經酶作用可形成產物。一個生化反應的底物往往同時也是另一個化學反應的產物。

substrate /s'ʌbstr,et/

共發現 8 筆關於 [substrate] 的資料 (解釋內文之英文單字均可再點選進入查詢)

資料來源(1): pydict data [pydict]

substrate
基層;基座;襯底;基底

資料來源(2): Taiwan MOE computer dictionary [moecomp]

substrate
基體

資料來源(3): Network Terminology [netterm]

substrate
基體

資料來源(4): Webster's Revised Unabridged Dictionary (1913) [web1913]

Substrate \Sub"strate\, n.
A substratum. [R.]

資料來源(5): Webster's Revised Unabridged Dictionary (1913) [web1913]

Substrate \Sub"strate\, a.
Having very slight furrows. [R.]

資料來源(6): Webster's Revised Unabridged Dictionary (1913) [web1913]

Substrate \Sub*strate"\, v. t. [L. substratus, p. p. of
substrahere. See {Substratum}.]
To strew or lay under anything. [Obs.]

The melted glass being supported by the substrated
sand. --Boyle.

資料來源(7): WordNet (r) 2.0 [wn]

substrate
n 1: the substance acted upon by an enzyme or ferment
2: any stratum lying underneath another [syn: {substratum}]

資料來源(8): Free On-line Dictionary of Computing [foldoc]

substrate

<hardware> The body or base layer of an {integrated circuit},
onto which other layers are deposited to form the circuit.
The substrate is usually Silicon, though Sapphire is used for
certain applications, particularly military, where radiation
resistance is important. The substrate is originally part of
the {wafer} from which the {die} is cut. It is used as the
electrical {ground} for the circuit.

Noun
reactant

(chemistry) any of the participants present at the start of a chemical reaction