Answer:
Please find the detailed explanation of this statement below
Explanation:
Firstly, a repressed gene is a gene whose expression has been inhibited or repressed. The lac operon in E.coli bacteria is a regulatory unit containing structural genes, a single promoter and operator regions. The promoter is the region where the transcription enzyme (RNA polymerase) binds to in order to transcribe the genes in the lac operon. The structural genes in the lac operon can only be expressed in the presence of lactose sugar.
However, in the absence of lactose, LAC REPRESSOR, which is a transcription factor (protein), prevents the binding of RNA polymerase to the PROMOTER region by binding to the OPERATOR region of the lac operon. This inhibits the expression of the lactose genes in the operon.
Note that, the structural genes in the lac operon (lacZ, lacY, lacA) code for proteins that help break down lactose sugar for energy in the E.coli bacteria. Therefore, a bacteria cell with a repressed lac operon will be unable to degrade lactose sugar.
<h2>Transportation across the membrane</h2>
Explanation:
(a) Simple diffusion; Faciliated diffusion-Directions in which two transported solutes move
- In simple diffusion diffusion of non polar compounds across the membrane and along the concentration gradient without the involvement of protein whereas in case of facilitated diffusion membrane transport proteins that facilitate movement pf molecules across the membrane down its concentration gradient
- Both the diffusions does not require energy
(b) Facilitated diffusion; active transport-Direction the solute moves relative to its concentration gradient
- In facilitated diffusion membrane transport proteins that facilitate movement of molecules across the membrane down its concentration gradient without the expenditure of energy
- Active transport drives transportation of solute against the concentration gradient across the membrane
(c) Simple diffusion; Active transport-Directions in which two transported solutes move and Direction the solute moves relative to its concentration gradient
- In simple diffusion diffusion of non polar compouds across the membrane and along the concentration gradient without the involvement of protein and energy
- Active transport drives transportation of solute against the concentration gradient across the membrane;secondary active transporters coupled with transportation of two solute molecules
(d) Direct active transport; Indirect active transport-Direction the solute moves relative to its concentration gradient or its electrochemical potential
- Direct active transport use direct energy such as ATP hydrolysis,oxidation and sunlight energy
- Indirect active transport use indirect energy such as chemical gradient,electrochemical gradient established by direct active transporters;one solute moves along the concentration gradient while other moves against the concentration gradient
(e) Symport; Antiport-Direction in which two transported solutes move
- In symport both the solute molecules move in same direction;coupled with primary active transport(direct transport)
- In antiport both the solutes moves in opposite direction;coupled with secondary active transport(indirect transport)
(f) Uniport; coupled transport-Directions in which two transported solutes move
- Uniport is the transport of single solute across the membrane
- Coupled transport is the transport of two solute molecules across the membrane;it may be symport or antiport
(g) P-type ATPase; V-type ATPase-Kinetics of solute transport
- P-type ATPase always transport cations and undergoes phosphorylation
- V-type ATPase(here V stands for vacuole) transport protons and no phosphorylation occurs;catalytic activity is not reversible
- Both are types of primary active transporters
Answer:
it is better to bread with a chest nut
Explanation: because u get to make an albino horse and there cool and but they dont have the same things
