It is possible for a cell to make proteins that last for months; hemoglobin in red blood
cells
is a good example. However, many proteins are not this long-lasting. They may be degraded in days or even hours.
Can differentiated cells produce clones by regaining?
Can differentiated cells produce clones by regaining the potential to express genes that have been silenced?
Yes
. Under the right conditions, single differentiated cells, such as a root cell from a carrot, can grow and divide and eventually become a fully functional adult plant. This can occur in animal cells as well.
Which of the following would be most likely to lead to cancer?
The most common risk factors for cancer include
aging, tobacco, sun exposure
, radiation exposure, chemicals, and other substances, some viruses and bacteria, certain hormones, family history of cancer, alcohol, poor diet, lack of physical activity, or being overweight.
Which of the following best describes the term operon?
An operon is
a region of DNA that consists of a single gene regulated by more than one promoter
. … An operon is a region of DNA that codes for a series of functionally related genes under the control of the same promoter. This arrangement of genes is common in bacteria.
Is every protein in every cell being made all the time?
Within any cell,
only a proportion of proteins are produced at any one time
. Proteins that perform essential roles are produced constantly, while others are expressed only when they are needed.
What increases gene expression?
Activators
enhance the interaction between RNA polymerase and a particular promoter, encouraging the expression of the gene. Activators do this by increasing the attraction of RNA polymerase for the promoter, through interactions with subunits of the RNA polymerase or indirectly by changing the structure of the DNA.
How many unique proteins are in humans?
In humans, up to ten different proteins can be traced to a single gene. Proteome: It is now estimated that the human body contains
between 80,000 and 400,000 proteins
. However, they aren’t all produced by all the body’s cells at any given time. Cells have different proteomes depending on their cell type.
What are the best cells to clone from?
Stem cells harvested from embryos rather than adults
remain the most powerful for cloning and other purposes; Yang’s team showed that cloning from such cells succeeded in 49 percent of attempts and led to 18 mouse pups.
Why do cells make proteins with such a short life?
Short-lived proteins
enable the cells to adjust (control) gene expression when this is critical to their well-being
.
What does it mean if a cell is multipotent?
Definition. Multipotent stem cells are
cells that have the capacity to self-renew by dividing and to develop into multiple specialised cell types present in a specific tissue or organ
. Most adult stem cells are multipotent stem cells.
What are the 7 warning signs of cancer?
- Change in bowel or bladder habits.
- A sore that does not heal.
- Unusual bleeding or discharge.
- Thickening or lump in the breast or elsewhere.
- Indigestion or difficulty in swallowing.
- Obvious change in a wart or mole.
- Nagging cough or hoarseness.
What are the top 10 causes of cancer?
- Cancer syndromes.
- Smoking.
- Materials.
- Alcohol.
- Diet.
- Obesity.
- Viruses.
- Bacteria and parasites.
What are the four most common cancers in us?
- 1 – Skin cancer. Skin cancer is divided into the non-melanoma and melanoma categories. …
- 2 – Lung cancer. …
- 3 – Prostate cancer. …
- 4 – Breast cancer. …
- 5 – Colorectal cancer. …
- 6 – Kidney (renal) cancer. …
- 7 – Bladder cancer. …
- 8 – Non-Hodgkin’s lymphoma.
Which best describes the lac operon?
Which of the following BEST describes catabolite repression of the lac operon? The operon is
transcriptionally active when an activator protein binds to the promoter in the absence of glucose
. … Catabolite or glucose repression of the lac operon is a regulatory system, which depends on the levels of cAMP in the cell.
How do miRNA recognize a particular target mRNA?
How do miRNA recognize a particular target mRNA? … 1)
The miRNA and mRNA have the same sequence so they base pair
. 2) The miRNA sequence is complementary to the mRNA sequence so they base pair. 3) The binding of miRNA complex to RISC alters the RISC complex so these proteins bind directly to the mRNA.
What is an operon and where is it found?
More specifically, an operon is
a segment of DNA containing adjacent genes including structural genes, an operator gene, and a regulatory gene
. … Operons are found in many prokaryotic organisms (bacteria, viruses and some algae) and have yielded valuable insights into microbial genetics. See also: Selfish operon.
