Answer:
c. a natural disaster
Explanation:
A limiting factor in an ecosystem can either be density dependent or density independent. A density independent limiting factor is that which does not rely on the density of a population to affect it's size.
A density independent factor affects the population size irrespective of how densely populated the population is. Examples of density independent limiting factors that can affect a population are natural disasters like fire outbreak, hurricane, earthquake etc.
Answer:
Basement membrane
Explanation:
Epithelial tissues is one of the four types of tissues. They are widespread throughout the body and form the covering of all body surfaces, line body cavities and hollow organs, and are the major tissue in glands .
They perform a lot of functions such as absorption, excretion, filtration, diffusion, and sensory reception.
They are anchored to the underlying connective tissue by basement membrane. A thin, fibrous, extracellular matrix of tissue.
The basement membrane acts as a mechanical barrier that prevents malignant cells from invading the deeper tissues.
Answer:
Basically the translation of CK-B protein is inhibited in the U937D cells, despite the fact that the CK-B protein is bounded to the ribosomes. This is because(<u>mechanisms)</u> the translation is inhibited by the binding of translational repressors to the 3’UTR of the CK-B mRNA rather than the actual CK-B mRNA 3'UTR.
Furthermore, the soluble protein inhibitions is due to the reaction of the U937 cells to the short RNA sequences with the 3’UTR.
<u>The introduction of these sequences(shot segement of RNA) </u>into the U937D cells leads to CK-B synthesis. This makes 3’UTR sequences to bind to the translational repressor proteins, thus preventing them from binding to the CK-B mRNA
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COMPLETED QUE.
A common feature of many eukaryotic mRNAS is the presence of a rather long 3' UTR, which often contains consensus sequences. Creatine kinase B (CK-B) is an enzyme important in cellular metabolism. Certain cells—termed U937D cells—have lots of CK-B mRNA, but no CK- B enzyme is present. In these cells the 5’ end of the CK-B mRNA is bound to ribosomes, the mRNA is apparently not translated. Something inhibits the translation of the CK-B mRNA in these cells. Researchers introduced numerous short segments of RNA containing only 3’UTR sequences into U937D cells. As result, the U937D cells began to synthesize the CK-B enzyme, but the total amount of CK-B mRNA did not increase. The introduction of short segments of other RNA sequences did not stimulate the synthesis of CK-B; only the 3’UTR sequences turned on the translation of the enzyme. Based on these results, <u>purpose a mechanism for how CK-B translation is inhibited in U937D cells. Explain how the introduction of short segments of RNA containing the 3'UTR sequences might remove the inhibition.</u>
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Explanation:
Explanation:
It can do three things:
1) It can erode/weather to form new sediments that later become a new sedimentary rock.
2) It can undergo heat and pressure changes and become metamorphic rock.
3) It can be melted and solidify into igneous rock.
Once this happens, it can repeat any of these processes.
Organs<span> that aid in the process of </span>digestion<span> but </span>never <span>touch the </span>food<span> product.</span>
