Answer: Options A, B, C and D are correct.
Explanation: They can trigger the activity of histone acetyltransferases.
These RNAs functions by binding to histone-modifying complexes, to DNA binding proteins (including transcription factors), and even to RNA polymerase II.
They can silence genes by promoting the formation of euchromatin by arranging hetero- or euchromatic regions into close proximity may stabilize these domains or it may control the spreading of post-translational modifications (PTMs) to nearest chromatin.
They are actively involved in X chromosome inactivation.
They can regulate the translation and stability of mRNAs.
In Eukaryotic cells RNA transcription is a closely regulated process. Transcription of a lncRNA may regulate the transcription of nearby mRNA genes, either positively (maintaining active chromatin structure) or negatively (for example, colliding polymerases). In these cases, the RNA product may have no importance at all, or it could have an additional function.
Answer:
A: Oxygen levels are low and, therefore, more red blood cells are produced, giving the athletes an advantage when competing at lower altitudes.
Explanation:
<em>At high altitudes, the partial pressure of oxygen is lower compared to lower altitudes</em>. The body system try to adjust to lower oxygen level by undergoing several physiological changes. Depending on the duration spent in high altitude, the body can either try to adjust in the short term or acclimatize for a longer term.
One of the processes the body undergoes during acclimatization is an increase in red blood cell production. The kidney secretes erythropotein in response to inadequate oxygen in body tissues, and this makes the liver to increase erythrocyte production.
The increase in red blood cell production correspondingly increases the oxygen-carrying capacity of the blood as a result of increased hemoglobin. This condition persists for a few weeks even after the body returns to lower altitude where oxygen is adequate. Increased oxygen capacity means the rate of energy production (through respiration) within the body will also increase
<em>Hence, those who acclimatize to high altitude usually experience increased capillary density, tissue perfusion and improved athletic performance at lower altitudes. </em>
The correct option is A.
Answer:
Hormones activate target cells by diffusing through the plasma membrane of the target cells. Hormones circulate throughout the body via the blood, contacting just about all cells. The "target" cells for a particular hormone have receptors, either on the cell membrane
Explanation:
Answer:
I think when the earth was created it took a time. Then dinosaurs came. Then tey extinct because falling of asteroid on Earth.Then after a period of time the sea,mountains and other natural things were made again.
B. malignant is the correct answer