What is the function of operator region in an operon?
Operator Definition 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 lac operon model?
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.
Why are operons not found in eukaryotes?
When an operon is transcribed, all of the genes on the operon are on the same mRNA. Operons occur in prokaryotes, but not eukaryotes. In eukaryotes, each gene is made on individual mRNAs and each gene has its own promoter. Cells can’t afford to waste energy making genes if they don’t need them.
Why do bacteria have operons?
Operon, genetic regulatory system found in bacteria and their viruses in which genes coding for functionally related proteins are clustered along the DNA. This feature allows protein synthesis to be controlled coordinately in response to the needs of the cell.
What cells do platelets come from?
Platelets are produced from very large bone marrow cells called megakaryocytes. As megakaryocytes develop into giant cells, they undergo a process of fragmentation that results in the release of over 1,000 platelets per megakaryocyte.
Is Thrombocyte a white blood cell?
The three classes of formed elements are the erythrocytes (red blood cells), leukocytes (white blood cells), and the thrombocytes (platelets).
What is the function of white blood cells?
White blood cells are part of the body’s immune system. They help the body fight infection and other diseases. Types of white blood cells are granulocytes (neutrophils, eosinophils, and basophils), monocytes, and lymphocytes (T cells and B cells).
What are the three roles of white blood cells?
For example: 1) they can cause the different pathogens to stick together, so phagocytes can ingest them more easily 2) acting as a label on the pathogens so phagocytes recognise them more easily 3) cause the pathogen cells to burst 4) neutralise the toxins produced by the pathogens Finally, some lymphocytes develop …