PLEASE HELP AND NO LINKS PLEASE!!!

For this assignment you will complete an illustration(s) (by hand) of how the lac operon works. You should be sure to include de

Fantom [35]

<h2>Lac operon </h2>

Explanation:

Lac operon present in prokaryotic chromosomes whose product involves in transportation and catabolism of lactose

Lac operon consists of three structural genes called Lac Z,Lac Y and Lac A and a regulatory element(promoter and operator)
Lac I gene is present outside the Lac operon,act as regulatory gene and control the expression of Lac operon genes
Lac Z codes for β galactosidase which converts lactose into allolactose
Lac Y codes for Lac permease which act as a membrane transporter and transport lactose into the cells
Lac A codes for transacetylase which neutralize the toxic effects of lactose

Lac operon in absence of lactose

In absence of lactose Lac operon exists in switch off state
Lac I gene produces Lac repressor which binds to operator region and prevent binding of RNA Polymerase thus blocks transcription

Lac operon in presence of lactose

In presence of lactose Lac operon exists in switch on state
In presence of lactose few molecules of Lac operon enzyme catalyse conversion of lactose to allolactose
Allolactose act as an inducer,binds to the Lac repressor and induce conformational changes causing dissociation of Lac repressor from operator
In absence of Lac repressor RNA Polymerase binds to the promoter and starts transcription of genes which catabolize lactose

Lac promoter is a weak promoter and direct transcription of Lac operon genes in very low level in presence of lactose

For higher level expression of Lac operon genes,operon system require conversion of weak promoter to strong promoter which is always mediated by catabolite protein-cAMP complex(CAP-cAMP complex)
CAP cAMP complex binds to the upstream of promoter called CAP binding site and stimulate expression of Lac operon genes by facilitating binding of RNA Polymerase
Catabolite activator protein(CAP) or cAMP receptor protein(CRP) activate when cAMP binds
cAMP is a secondary messenger synthesized from ATP and act as co-activator of CRP
With respect to CAP cAMP complex Lac operon system is positively controlled
In prokaryotic cell cAMP is very low when glucose concentration is relatively high and vice versa
At high concentration of glucose the growth rate is maximum and lactose catabolism is repressed called catabolite repression

6 0

3 years ago

Mutations in DNA include deletions and insertions. These types of mutations:

pantera1 [17]

Answer:

(A). Result in different amino acids to be read due to frame shifts

Explanation:

Insertion or deletion mutations (or Indel mutations) can be defined as mutations in DNA due to insertion (addition) or deletion of nucleotide bases in DNA.

These mutations lead to change in reading frames (sequence of codons), which leads to formation of protein having completely different amino acid sequence. Hence, these mutations are also cause frameshift mutations.

This is due due to triplet nature of genetic codes as insertion or deletion of one or more bases (but not three) would change change in codon sequence and mutated sequence can form a non-functional or truncated protein.

Thus, the correct answer is option (A).

6 0

3 years ago

3) Which one of the following factors generally causes the quickest loss of species diversity within an

Lesechka [4]

Answer: A) Habitat loss

Explanation: While all four options are viable, habitat loss decreases biodiversity the fastest.

6 0

3 years ago

Help, i have info there and i need the punnet square filled! plz

maxonik [38]

Answer:

X. x

Y /. XY / Yx

----------

y /. Xx / xy

Explanation:

hope this helps

6 0

3 years ago

Gene regulations in eukaryotes

mote1985 [20]

Answer:

Gene regulation in eucaryotic cells represents mechanisms that influence gene expression.

Explanation:

This gene expression is regulated via repressors or activators of transcription.

Gene expression is a process that contains information from a transcript gene and translates it into a functional gene product. End products of gene expression are proteins.

Gene regulation is a process that cells and viruses are using to regulate the transformation of gene information into gene products.

Transcription factors are those proteins that regulate gene transcription. Those factors help the real genes to enter the right cells in the body.

The expression of eukaryotic genes is controlled by transcription. This transcription is controlled by proteins that are connecting to regulatory sequences and change the RNA activity. Gene regulation process is developed by combining different proteins of regulation.

5 0

3 years ago