The tundra biome has permafrost
Sildenafil, also known as viagra, treats <span>erectile dysfunction.
</span>Isosorbide dinitrate- is used to treat or prevent angina.
They both dilate blood vessels, making it easier for blood to flow.
This drugs taken together are not recommended because it may cause blood pressure to fall
excessively, which can lead to cardiovascular collapse.
Other side effects are: dizziness, fainting,
headache, heart palpitations, and priapism (prolonged and
painful erection)
Anti-parallel DNA strands refer to those DNA molecules which contain 2 DNA strands that were held together by hydrogen. In cases that the DNA strands are not anti-parallel the non-symmetrical hydrogen bond will not be possible and will cause some issues.
