In fetal life, the lungs are not expanded, so most of the blood from the right ventricle is shunted from the pulmonary artery to the aorta through the patent ductus arteriosus. With a few breaths the lungs expand, and blood flows from right ventricle to pulmonary artery into the lungs. Withdrawal of circulating prostaglandin from the mother plus bradykinins released from the expanding lung of the infant cause the ductus to close over a few minutes to hours. The closed ductus remains as the ligamentum arteriosum.
Answer:
b. Forward or reverse primers
Explanation:
Sanger sequencing is a technique of DNA sequencing based on the extension of DNA fragments with variable sizes terminated with dideoxynucleotides at the 3′ end. This technique was developed by Frederick Sanger in 1977. In Sanger sequencing, a short primer is added in order to bind by complementarity to the target DNA region of interest. Subsequently, a DNA polymerase adds nucleotides (A, T, C and G) in the 5'-3' direction. Finally, the extension of the DNA strand is stopped by adding dideoxynucleotides, which are nucleotide analogs (i.e., modified nucleotides) that act as DNA synthesis terminators.
"They are <span>multicellular" is not a characteristic of bacteria. Although it should be noted that the smallest life forms don't necessarily have to be bacterial. </span>
Answer/Explanation:
Cells of a similar type are organized together to make tissues. Different types of tisues come together to perform a similar function as part of organs.
For example, take the organ the stomach. There are various tissues that make up the stomach, including, for example, mucosa, and muscle tissue.
The mucosa tissue of the stomach is made up of secretory cells such as parietal cells, which secrete hydrochloric acid, and foveolar cells which produce mucus that protects the lining of the stomach.
