PROJECT BASED ASSIGNMENT : MEDICAL RESEARCH GROUP 161 by MDM NASHIMAH HABEEB https://padlet.com/MadamNash/Chapt6_161 The Chapter You Are Learning Today is Going To Save Someone's Lives Tomorrow en-us 2021-09-24 01:56:19 UTC 2024-08-11 13:20:35 UTC hello@padlet.com Project Solving Task MadamNash https://padlet.com/MadamNash/Chapt6_161/wish/1769670586 Assume that you have discovered two new strains of E.coli that has a mutation in the lac operon structures. One type of strain has mutation in operator region and another type in promoter region. Explain how this phenomenon would affect the metabolism of lactose.    

The bacterial lacZ gene: an important tool for metastasis research and evaluation of new cancer therapies. As the group of research scientist appointed by  Cancer Research Malaysia, SJMC  you are required to do research how this therapies will help  in term as alternative cancer treatment?

Project objective :
1. Applying the concept of lac operon process in prokaryotic cell
2. How to use LacZ in therapy
]]> 2021-09-27 02:06:44 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1769670586 PROJECT BASED LEARNING MadamNash https://padlet.com/MadamNash/Chapt6_161/wish/1769671500  


The link between perturbations in translational control and cancer etiology is becoming a primary focus in cancer research. It has now been established that genetic alterations in several components of the translational apparatus underlie spontaneous cancers as well as an entire class of inherited syndromes known as “ribosomopathies” associated with increased cancer susceptibility.  As the group of research scientist appointed by  Cancer Research Malaysia, SJMC  you are required to do research  how to control translation in cancer Etiology in term as alternative cancer treatment?

OBJECTIVE: 
1) Applying the concept of translation process in eukaryotic
2) How to inhibit translation process to Control in Cancer Etiology. 



]]> 2021-09-27 02:07:08 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1769671500 PROJECT BASED LEARNING- GENETIC ENGINEERING MadamNash https://padlet.com/MadamNash/Chapt6_161/wish/1769673369 When genes work properly, they tell cells when it is the right time to grow and divide. When cells divide, they make exact copies of themselves. One cell divides into 2 identical cells, then 2 cells divide into 4, and so on. In adults, cells normally grow and divide to make more cells only when the body needs them, such as to replace aging or damaged cells.

 Existing cells in our body divides through the process of meiosis and mitosis to produce new cells. The division of the cells would slowly halve the size of the genome until each cell would die if there is no new copies of DNA is made before undergoes cell division process, which probably would not take long. Therefore, S phase of interphase in cell cycle of a cell is important in keeping the cells alive. What is the process involved in copying DNA in S phase?

A cancer cell doesn’t act like a normal cell. It starts to grow and divide out of control instead of dying when it should. They also don’t mature as much as normal cells so they stay immature. Although there are many different types of cancer, they all start because of cells that are growing abnormally and out of control. Cancer can start in any cell in the body.  Cisplatin is one type of drugs used in cancer treatment. Discover how this drugs overcome the growing of cancerous cell. 

OBJECTIVE:
1) Applying the concept of replication process in eukaryotic
2) How to inhibit replication process by using drugs]]> 2021-09-27 02:07:57 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1769673369 PROJECT BASED LEARNING MadamNash https://padlet.com/MadamNash/Chapt6_161/wish/1776578776 PROJECT BASED LEARNING- TASK : The realization that the increase in rRNA expression has an active role in cancer progression, not only through increased protein synthesis and thus proliferative capacity but also through control of cellular check points and chromatin structure, has opened up new therapeutic avenues for the treatment of cancer through direct targeting of Pol I transcription.  As the group of research scientist appointed by  Cancer Research Malaysia, SJMC  you are required to do research  which  drugs can be used to inhibit targeting of Pol I transcription in term as alternative cancer treatment?

OBJECTIVE: 
1) Applying the concept of transcription process in eukaryotic
2) How to inhibit transcription process by using drugs]]> 2021-09-29 02:29:11 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1776578776 How Replication is inhibited MadamNash https://padlet.com/MadamNash/Chapt6_161/wish/1776584696 2021-09-29 02:31:27 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1776584696 MadamNash https://padlet.com/MadamNash/Chapt6_161/wish/1776794218 2021-09-29 03:57:14 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1776794218 LacZ and cancer theraphy MadamNash https://padlet.com/MadamNash/Chapt6_161/wish/1776856824 2021-09-29 04:29:56 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1776856824 https://padlet.com/MadamNash/Chapt6_161/wish/1782777478 2021-10-01 00:23:22 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782777478 translation process occur in ribosome balkistasya https://padlet.com/MadamNash/Chapt6_161/wish/1782778138 2021-10-01 00:23:42 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782778138 https://padlet.com/MadamNash/Chapt6_161/wish/1782778540 2021-10-01 00:23:56 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782778540 https://padlet.com/MadamNash/Chapt6_161/wish/1782780351 2021-10-01 00:24:53 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782780351 Genetic Code https://padlet.com/MadamNash/Chapt6_161/wish/1782783310 2021-10-01 00:26:33 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782783310 https://padlet.com/MadamNash/Chapt6_161/wish/1782791784 2021-10-01 00:30:59 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782791784 ribosome is a non membrane organelle that acts as the site for protein systhesis balkistasya https://padlet.com/MadamNash/Chapt6_161/wish/1782798298 Organelles that are not fluid-filled don't need to be separated from the rest of the cell in the same way, so they don't have a membrane. These are the non-membrane bound organelles


]]> 2021-10-01 00:34:06 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782798298 https://padlet.com/MadamNash/Chapt6_161/wish/1782803958 2021-10-01 00:36:53 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782803958 m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1782840478 2021-10-01 00:52:50 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782840478 The ribosome usually moves forward from the start to the stop codon on the mRNA in exact steps of one codon at a time balkistasya https://padlet.com/MadamNash/Chapt6_161/wish/1782843966 Proteins are synthesized from mRNA templates by a process that has been highly conserved throughout evolution . All mRNAs are read in the 5´ to 3´ direction,]]> 2021-10-01 00:54:27 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782843966 m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1782844991 2021-10-01 00:54:54 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782844991 CODON https://padlet.com/MadamNash/Chapt6_161/wish/1782846995 2021-10-01 00:55:47 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782846995 Structure of ribosome balkistasya https://padlet.com/MadamNash/Chapt6_161/wish/1782853233 2021-10-01 00:58:34 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782853233 Pre-mRNA to mature mRNA m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1782858478 In bacteria, RNA transcripts are ready to act as messenger RNAs and get translated into proteins right away. In eukaryotes, things are a little more complex, though in an pretty interesting way. The molecule that's directly made by transcription in one of your (eukaryotic) cells is called a pre-mRNA, reflecting that it needs to go through a few more steps to become an actual messenger RNA (mRNA). These are:

Addition of a 5' cap to the beginning of the RNA

Addition of a poly-A tail (tail of A nucleotides) to the end of the RNA

Chopping out of introns, or "junk" sequences, and pasting together of the remaining, good sequences (exons)

Once it's completed these steps, the RNA is a mature mRNA. It can travel out of the nucleus and be used to make a protein.


]]> 2021-10-01 01:00:58 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782858478 Initiation of translation https://padlet.com/MadamNash/Chapt6_161/wish/1782858819 2021-10-01 01:01:07 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782858819 Stages in translation balkistasya https://padlet.com/MadamNash/Chapt6_161/wish/1782861220 Translation of an mRNA molecule by the ribosome occurs in three stages
  •  initiation
  •  elongation
  • termination
]]> 2021-10-01 01:02:15 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782861220 Introns and Exons m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1782868673 2021-10-01 01:05:36 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782868673 RNA Splicing m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1782875101 In RNA splicing, specific parts of the pre-mRNA, called introns are recognized and removed by a protein-and-RNA complex called the spliceosome. Introns can be viewed as "junk" sequences that must be cut out so the "good parts version" of the RNA molecule can be assembled.

The pieces of the RNA that are not chopped out are called exons. The exons are pasted together by the spliceosome to make the final, mature mRNA that is shipped out of the nucleus.]]> 2021-10-01 01:08:24 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782875101 m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1782884650 2021-10-01 01:12:28 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782884650 10 (1).What is structural gene https://padlet.com/MadamNash/Chapt6_161/wish/1782887014 A term derived from the lac operon, structural genes are typically viewed as those containing sequences of DNA corresponding to the amino acids of a protein that will be produced, as long as said protein does not function to regulate gene expression. Structural gene products include enzymes and structural proteins. 
(nabilah)]]> 2021-10-01 01:13:30 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782887014 CISPLATIN : HOW IT WORKS? https://padlet.com/MadamNash/Chapt6_161/wish/1782894233 Cisplatin is chemotherapy medicine used to treat a variety of cancers, including bladder cancer,cervical cancer, head and neck cancer, lung cancer, 🤬 cancer and cancer of the ovaries.

Cisplatin works by stopping the cancer cells from multiplying. It does this by binding together the strands of the cells' genetic material, DNA. DNA is needed for growth and multiplication of cells. Cisplatin damages the DNA or RNA inside the cancer cells that tells the cell how to copy itself in division and so prevents them from multiplying. If the cells are unable to divide, they die. The faster the cells are dividing, the more likely it is that chemotherapy will kill the cells, causing the tumor to shrink. 
]]> 2021-10-01 01:16:35 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782894233 Translation Advanced look https://padlet.com/MadamNash/Chapt6_161/wish/1782904148 2021-10-01 01:20:32 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782904148 10 (2). https://padlet.com/MadamNash/Chapt6_161/wish/1782904658 2021-10-01 01:20:45 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782904658 ANTICODON https://padlet.com/MadamNash/Chapt6_161/wish/1782906969 2021-10-01 01:21:44 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782906969 DNA Replication https://padlet.com/MadamNash/Chapt6_161/wish/1782908247 - the process of copying and duplicating DNA molecule
-DNA replication occurs in the cytoplasm of prokaryotes and in the nucleus of eukaryotes 
-During cell division, DNA replication occur during interphase
 ]]> 2021-10-01 01:22:19 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782908247 The 3 proposed models of DNA replication https://padlet.com/MadamNash/Chapt6_161/wish/1782913448 2021-10-01 01:24:32 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782913448 Elongation of translation https://padlet.com/MadamNash/Chapt6_161/wish/1782916247 2021-10-01 01:25:43 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782916247 In 1957, Matthew s. Meselson and Franklin W. Stahl confirmed semiconservative replication of DNA experimentally https://padlet.com/MadamNash/Chapt6_161/wish/1782917183 2021-10-01 01:26:07 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782917183 10(3). https://padlet.com/MadamNash/Chapt6_161/wish/1782922353 2021-10-01 01:28:17 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782922353 https://padlet.com/MadamNash/Chapt6_161/wish/1782928140 2021-10-01 01:30:46 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782928140 How drugs inhibit transciption. m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1782928308 2021-10-01 01:30:51 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782928308 Complementary base pairing https://padlet.com/MadamNash/Chapt6_161/wish/1782933482 2021-10-01 01:33:01 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782933482 9. https://padlet.com/MadamNash/Chapt6_161/wish/1782934206 Enhancers are short regulatory elements of accessible DNA that help establish the transcriptional program of cells by increasing transcription of target genes.]]> 2021-10-01 01:33:20 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782934206 Protein Synthesis (Translation) https://padlet.com/MadamNash/Chapt6_161/wish/1782950721 2021-10-01 01:40:37 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782950721 haloooo MadamNash https://padlet.com/MadamNash/Chapt6_161/wish/1782964285 2021-10-01 01:46:39 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782964285 2.In what type of cell operon system can be found? https://padlet.com/MadamNash/Chapt6_161/wish/1782969937 -Operons occur primarily in prokaryotes but also in some eukaryotes.
-A prokaryotic cell is a type of cell that does not have a true nucleus or membrane-bound organelles. 

]]> 2021-10-01 01:48:55 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1782969937 TRANSLATION INHIBITORS IN CANCER TREATMENT https://padlet.com/MadamNash/Chapt6_161/wish/1792301811 2021-10-05 08:41:09 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1792301811 1. What is an operon system? https://padlet.com/MadamNash/Chapt6_161/wish/1792741692 An operon is a cluster of functionally-related genes that are controlled by a shared operator. Operons consist of multiple genes grouped together with a promoter and an operator.

There are three basic components to an operon

  • Promoter 
  • Operator
  • Structural genes 



what is an operator?
-An operator is a genetic sequence which allows proteins responsible for transcription to attach to the DNA sequence.
-The gene, or genes, which get transcribed when the operator is bound are known as the operon.

what is a promoter?
-A type of DNA sequence that activates the expression of the lactose genes by acting as an RNA polymerase binding site for the lac operon.

what is a structural gene?
-Structural genes are those genes that control the production of a protein that performs a structural role in cell.


]]> 2021-10-05 12:13:21 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1792741692 Termination (closer look) https://padlet.com/MadamNash/Chapt6_161/wish/1792810575 2021-10-05 12:36:26 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1792810575 3. What are the example of organism in prokaryotic cells? https://padlet.com/MadamNash/Chapt6_161/wish/1792816664 -Example of Prokaryotes-
  • bacteria -They constitute a large domain of prokaryotic microorganisms and  are small single-celled organisms like the bacterium Escherichia coli (E. coli)

]]> 2021-10-05 12:38:14 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1792816664 The Role of Translation Control in Tumorigenesis and Its Therapeutic Implications https://padlet.com/MadamNash/Chapt6_161/wish/1793000457 2021-10-05 13:27:00 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1793000457 4. Example of operon system that operate in E.coli. https://padlet.com/MadamNash/Chapt6_161/wish/1793029117 The lactose metabolism system (lac operon)

  • The lac operon is an operon, or group of genes with a single promoter (transcribed as a single mRNA). The genes in the operon encode proteins that allow the bacteria to use lactose as an energy source.
  • The lac operon of E. coli contains genes involved in lactose metabolism. It's expressed only when lactose is present and glucose is absent.

]]> 2021-10-05 13:33:12 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1793029117 Stages of transcription https://padlet.com/MadamNash/Chapt6_161/wish/1794401312 Elongation
- is a subsequent addition of RNA nucleotides complementary to the DNA template strands.

1. Direction of RNA polymerase elongating is 3' to 5'. RNA polymerase is moves along the 3' to 5' DNA template, free nucleotides are added in the 5' to 3' direction complementary to DNA template.
2. RNA nucleotide is being added at the 3' end of the RNA transcript/strand.
3. Product of this process is RNA.
4. Bond that links between these nucleotides is ester bond. A phosphodiester bond is formed between sugar base of one nucleotide and phosphate group of the adjacent nucleotide .
5. Type of nucleotide that makes the product is adenine (A), guanine (G), cytosine (C), and uracil (U). During elongation, nucleotides are added to the growing RNA strands according to the same base pairing rules as for DNA. ]]> 2021-10-05 20:48:45 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794401312 13. What is the function of lac operon in E. coli? m10833061 https://padlet.com/MadamNash/Chapt6_161/wish/1794728244 The lac operon is an operon, or group of genes with a single promoter (transcribed as a single mRNA). The genes in the operon encode proteins that allow the bacteria to use lactose as an energy source.
E. coli bacteria can break down lactose, but it's not their favorite fuel. If glucose is around, they would much rather use that.


]]> 2021-10-06 00:07:07 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794728244 14. If glucose is present, is the lac operon activated? m10833061 https://padlet.com/MadamNash/Chapt6_161/wish/1794732880 No, The lac operon of E. coli contains genes involved in lactose metabolism. It's expressed only when lactose is present and glucose is absent.
The lac operon has an added level of control so that the operon remains inactive in the presence of glucose even if lactose also is present. High concentrations of glucose catabolites produce low concentrations of cAMP, which must form a complex with CAP to permit the induction of the lac operon.


]]> 2021-10-06 00:09:35 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794732880 15. What happen to the lac operon in the presence of lactose? m10833061 https://padlet.com/MadamNash/Chapt6_161/wish/1794736256
  • If lactose is available, the lac repressor will be released from the operator (by binding of allolactose). This allows RNA polymerase to move forward on the DNA and transcribe the operon.
  • These two events in combination – the binding of the activator and the release of the repressor – allow RNA polymerase to bind strongly to the promoter and give it a clear path for transcription. They lead to strong transcription of the lac operon and production of enzymes needed for lactose utilization.



    • ]]>     2021-10-06 00:11:28 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794736256     16. What is the isomer of lactose? m10833061 https://padlet.com/MadamNash/Chapt6_161/wish/1794740354 Lactose occurs in two isomeric forms, α-lactose and β-lactose
    α and β, differing only in the configuration of the hydroxyl group at the anomeric hemiacetal carbon. α has an axial hydroxyl whereas β hydroxyl is equatorial


    ]]>     2021-10-06 00:13:46 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794740354     How Chemotherapy Drugs Works m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1794748541 2021-10-06 00:17:57 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794748541 https://courses.lumenlearning.com/wm-biology1/chapter/reading-steps-of-genetic-transcription/ aleeyashuhadah https://padlet.com/MadamNash/Chapt6_161/wish/1794753062 Initiation is the beginning of transcription. It occurs when the enzyme RNA polymerase binds to a region of a gene called the promoter. This signals the DNA to unwind so the enzyme can ‘‘read’’ the bases in one of the DNA strands. The enzyme is now ready to make a strand of mRNA with a complementary sequence of bases.]]> 2021-10-06 00:20:10 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794753062 How it works? m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1794757130 2021-10-06 00:22:07 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794757130 m3396234 https://padlet.com/MadamNash/Chapt6_161/wish/1794759816 2021-10-06 00:23:20 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794759816 https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/transcription-initiation aleeyashuhadah https://padlet.com/MadamNash/Chapt6_161/wish/1794764283 Stages of the Transcription Initiation Process
    Transcription initiation is the phase during which the first nucleotides in the RNA chain are synthesized. It is a multistep process that starts when the RNAP holoenzyme binds to the DNA template and ends when the core polymerase escapes from the promoter after the synthesis of approximately the first nine nucleotides.

    -The stages of the transcription initiation process, which are summarized in Figure 2, can be described in terms of the types of interaction between the RNAP and the nucleic acids that are involved

    -The first stage in transcription initiation is the formation of a complex between the holoenzyme and the DNA sequence at the promoter, which is in the form of a double-stranded DNA. 



    ]]>     2021-10-06 00:25:16 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794764283     https://padlet.com/MadamNash/Chapt6_161/wish/1794966360 2021-10-06 01:47:06 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1794966360 11. https://padlet.com/MadamNash/Chapt6_161/wish/1796342555 RNA polymerase bind at promoter]]> 2021-10-06 12:55:27 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796342555 12 https://padlet.com/MadamNash/Chapt6_161/wish/1796399691 An inducer (allolactose or an analog) binds to the repressor and prevents its binding to the operator, thereby releasing the repression and allowing transcription of the lac operon.]]> 2021-10-06 13:11:34 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796399691 Q8. what is the gene that is not part of the operon system? https://padlet.com/MadamNash/Chapt6_161/wish/1796585885 The structural genes in the lac operon activate specific enzymes for the metabolism of lactose. From the above information, we have found that operon does not contain an enhancer in their structure. An enhancer has no specific role in the functioning of the operon. Enhancer sequences are regulatory DNA sequences. These sequences are bound by specific proteins called transcription factors. The binding of these proteins will enhance the transcription of an associated gene. They are not part of the operon structure.]]> 2021-10-06 13:59:09 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796585885 Q7. what are the components of lac operon https://padlet.com/MadamNash/Chapt6_161/wish/1796590597 An operon consists of
    i. an operator
    ii. promoter
    iii. regulator
    iv. structural genes    .

    ]]>     2021-10-06 14:00:19 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796590597     Q7. what are the components of lac operon https://padlet.com/MadamNash/Chapt6_161/wish/1796644251 2021-10-06 14:13:46 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796644251 Q6. what part in the operon that code enzymes? https://padlet.com/MadamNash/Chapt6_161/wish/1796657174 A typical operon consists of a group of structural genes that code for enzymes involved in a metabolic pathway, such as the biosynthesis of an amino acid. These genes are located contiguously on a stretch of DNA and are under the control of one promoter (a short segment of DNA to which the RNA polymerase binds to initiate transcription). A single unit of messenger RNA(mRNA) is transcribed from the operon and is subsequently translated into separate proteins]]> 2021-10-06 14:17:01 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796657174 Q5. who proposed the operon model in bacteria? https://padlet.com/MadamNash/Chapt6_161/wish/1796666453 The operon theory was first proposed by the French microbiologists François Jacob and Jacques Monod in the early 1960s. In their classic paper they described the regulatory mechanism of the lac operon of Escherichia coli, a system that allows the bacterium to repress the production of enzymes involved in lactose metabolism when lactose is not available.]]> 2021-10-06 14:19:25 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796666453 Q23. give the significance of the presence of lactose in E.coli. https://padlet.com/MadamNash/Chapt6_161/wish/1796824525 The lactose operon (lac operon) is an operon required for the transport and metabolism of lactose in E. coli and many other enteric bacteria. ... The gene product of lacZ is β-galactosidase which cleaves lactose, a disaccharide, into glucose and galactose.

    Lactose, being large and highly hydrophilic cannot pass through the E. coli cell membrane. Lactose permease is a membrane protein that allows lactose to enter the cell, moving down its concentration gradient.

    Therefore, when E. coli grows on sources other than lactose, such as carbon-based sources, these genes are not transcribed, leading to a very low concentration of these enzymes in the cell. In contrast, the presence of lactose considerably increases the synthesis of these enzymes

    ]]>     2021-10-06 15:00:12 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796824525     (padlet1.1)mutation occur at operator https://padlet.com/MadamNash/Chapt6_161/wish/1796828551 (Most mutations in the operator, the binding site for repressor,) lead to lower affinity for the repressor and hence less binding.  Thus these mutations allow continued transcription (and thus expression) of the lac operon even in the absence of inducer; this is referred to constitutive expression.]]> 2021-10-06 15:01:17 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796828551 Q17 What is function of the isomer? https://padlet.com/MadamNash/Chapt6_161/wish/1796887328 Chains of alpha glucose compose starch. Since the foundation of starch is alpha glucose, it can be easily broken down into simple sugars. Meanwhile, chains of beta glucose compose cellulose. Unlike starch, cellulose is not easy to break down; hence it is a perfect, building material. The tasty parts of plants are composed of starch while the hard parts of plants are made of cellulose.
     
    Since plants are our main sources for glucose, which comes in the form of starch and cellulose, we depend greatly on them. For plants to store sugar, they need chains of alpha glucose to build starch. For plants to build structural material, they need chains of beta glucose to create cellulose. Humans have the capacity to break down starch while we cannot break down cellulose. Though this is the situation, cellulose is still important in our body system because cellulose is otherwise known as fiber. Fiber plays an important role in our digestive system. There are animals which can digest cellulose, specifically livestock animals such as horses, and cows. Termites can also break down the strong, structural form of cellulose.
    ]]>     2021-10-06 15:17:21 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796887328     padlet 1.2 ( mutation at promoter) https://padlet.com/MadamNash/Chapt6_161/wish/1796893500 Similarly, mutations in the lac promoter are cis-acting, since they alter the binding site for RNA polymerase. When RNA polymerase cannot initiate transcription of the lac operon, none of the genes in the operon can be expressed irrespective of the function of the repressor. In general, trans-acting genes that regulate expression of genes on other DNA molecules encode diffusible products. In most cases these are proteins, but in some cases RNA molecules can act in trans to regulate gene expression.]]> 2021-10-06 15:19:01 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796893500 Q18 What happen to repressor protein after steps that occurs in Q (17)? https://padlet.com/MadamNash/Chapt6_161/wish/1796899163 Change the shape of repressor protein.]]> 2021-10-06 15:20:32 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796899163 Q19 Name the enzyme that binds to promoter site? https://padlet.com/MadamNash/Chapt6_161/wish/1796907546 RNA polymerase is the main transcription enzyme. Transcription begins when RNA polymerase binds to a promoter sequence near the beginning of a gene (directly or through helper proteins).]]> 2021-10-06 15:22:46 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796907546 Q20 What is the function of the enzyme mention in Q (19)? https://padlet.com/MadamNash/Chapt6_161/wish/1796911097 The binding of the activator and the release of the repressor – allow RNA polymerase to bind strongly to the promoter and give it a clear path for transcription. They lead to strong transcription of the lac operon and production of enzymes needed for lactose utilization.]]> 2021-10-06 15:23:44 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796911097 Q21 What is the function of each translated enzyme encoded by structural genes? https://padlet.com/MadamNash/Chapt6_161/wish/1796960023 Lac Z: encodes for β-galactosidase
    Lac Y: encodes for permease
    Lac A: encodes for transacetylase]]>     2021-10-06 15:36:37 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1796960023     The use of LacZ in therapy https://padlet.com/MadamNash/Chapt6_161/wish/1797445067 According to our findings based on this article it states ," As a benchmark, we have established in the present study the stable transfection or transduction of tumor cells with the lacZ gene encoding the bacterial enzyme β-galactosidase that metabolizes the chromogenic substrate 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-Gal) to an insoluble indigo blue dye and allows highly sensitive and selective histochemical blue staining of tumor cells in mouse tissue ex vivo down to the single cell level as shown here. This is a low-cost and not equipment-intensive tool, which allows precise validation of metastasis in studies assessing new anticancer therapies. "

    ]]>     2021-10-06 18:18:55 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1797445067     Findings related to the research. https://padlet.com/MadamNash/Chapt6_161/wish/1797450244 2021-10-06 18:20:54 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1797450244 22. What happened to the lac operon in the absence of lactose? m10833061 https://padlet.com/MadamNash/Chapt6_161/wish/1798119432 When lactose is absent the lac operon is switched off. This is becasue a repressor protein is produced which binds to the operator region. This prevents RNA polymerase from binding to the operon and therefore prevents transcription of the structual genes.]]> 2021-10-07 00:34:46 UTC https://padlet.com/MadamNash/Chapt6_161/wish/1798119432