<h2>Membrane potential </h2>
Explanation:
- Membrane potential represents charge difference across the membrane, all biological cells are negative inside (cytoplasm) and positive outside (due to difference in ionic distribution)
- In a typical neuron cell membrane potential of cytoplasm is negative at rest (when no stimulus is applied) hence called resting membrane potential
- Resting membrane potential of excitable cells is established by Na+ and K+pump
- Repolarization starts with the efflux of K+ by the opening of voltage gated K+ channels
- Voltage gated K+ channels starts to open when voltage gated Na+ channels becomes inactive
- Hyperpolarization occurs due to excessive efflux of K+ by voltage gated K+ channels
- Additional efflux of K+ occurs due to slow inactivation of voltage gated K+ channels
Answer: The science of naming and classifying organisms based on structural comparisons and genetic evidence, is known as taxonomy, a branch of biology.
Explanation: Taxonomy is very important. By categorizing organisms, this branch of biology helps scientists to exchange vital biological information, and therefore understand the diversity of species in our planet.
Phosphate groups are polar and allow the cell to exist in water.
The correct answer is: introns
Processing of mRNA is process that occurs only in eukaryotic cells. After the transcription, newly formed mRNA molecule is called and it must be processed into a messenger RNA (mRNA). Processing includes:
• Addition of a 5' cap to the beginning of the RNA
• Polyadenilation- addition of a poly-A tail (tail of A nucleotides) to the end of the RNA
• Splicing- removal of introns and linking the exons
After these steps mRNA is mature and used for the further steps (e.g. translation).
Sometimes some genes are alternatively spliced.
Shortness of breath or difficulty in breathing is also called dyspnea and can be acute or chronic. It has various causes, but mainly can be caused by a problem in the heart or the lungs. Since your heart and lungs are both involved in the transportation of the oxygen to the tissues and the removal of carbon dioxide, any problems occurring to these systems can affect breathing.
B-type Natriuretic Peptide (BNP) reflect the systolic and diastolic activity of the heart and its blood levels can show any heart failure. A BNP test and can help the nurse decide whether the cause of the dyspnea is a heart failure or some respiratory problem.