1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
True [87]
3 years ago
13

The lactose (lac) operon in E. coli is an example of a repressed gene when lactose is not available in a cell. In 3-5 sentences

Biology
1 answer:
irakobra [83]3 years ago
4 0

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.

You might be interested in
30) Which of these is NOT a way that large molecules, like glucose, can enter a cell? A) diffusion through the cell membrane. B)
Katen [24]

Answer:

the answer is B.

Explanation:

4 0
3 years ago
How do plasma cells form, and how do they help fight pathogens
xz_007 [3.2K]
<span>Plasma cells, they are also called  plasma B cells,  or effector B cells, are white blood cells that secrete large volumes of antibodies. They are transported by the blood plasma and the lymphatic system. Plasma cells originate in the bone marrow; B cells differentiate into plasma cells that produce antibody molecules closely modeled after the receptors of the precursor B cell. Once released into the blood and lymph,</span>
5 0
3 years ago
Read 2 more answers
What type of intercellular junction bands together adjacent cells, making the epidermis stronger?.
fenix001 [56]

Answer:

Tight or occluding junctions This type of junction is also called zonula occludens and is the most apical structure in the epithelial cell. Zonula occludens describes, that there is a formed band of tight junctions which encircles every cell.

Explanation:

8 0
2 years ago
How does mudstone turn into metamorphic rock?
Veseljchak [2.6K]

C is the answer.

Metamorphic rocks is when a rock changes under time and lots of pressure.

Sedimentary is rocks made of sediment.

Igneous rocks are rocks that are made of magma.

Knowing this, C is closest to the definition of metamorphic rocks.

7 0
2 years ago
Read 2 more answers
This part of the cell stores wastes, water for food
valentina_108 [34]

Answer:

<h2>Vacuoles</h2>

Explanation:

Vacuoles (located in the cell), store water, food and waste. It acts as a storage unit for the cell.

5 0
3 years ago
Read 2 more answers
Other questions:
  • 2 Summarize how the Ti plasmid is used to<br> insert genes into plant cells.
    14·1 answer
  • Sam came home from school with a cold caused by a virus and his sister, Ana, caught it from him. Sam got well and went back to s
    14·2 answers
  • How are the molecules in photosynthesis and cellular respiration similar? Please include descriptions of the molecules
    6·1 answer
  • Which characteristics describe the troposphere? Select two options.
    15·1 answer
  • What all body systems are affected by osteoporosis? (Osteoporosis is the thinning of your bones which leaves them weak and susce
    14·1 answer
  • A woman with a history of chronic alcohol abuse is admitted to the obstetric unit in labor. When assessing the newborn, which of
    12·1 answer
  • If red flowers were dominant over white flowers, R is for red flowers, what allele makes sense to represent
    7·1 answer
  • The texture of igneous rock that is composed of large mineral grains
    15·1 answer
  • What is the first step in a scientific investigation?
    5·2 answers
  • How does erosion affect the composition of soil in a region?
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!