A covalent bond is a chemical bond which involves the sharing of atoms.
The correct answer is hydronephrosis. Distention means being enlarged or swollen due to internal pressure. In this case, the internal pressure would be urine collecting in the kidney. This occurs when the urine is unable to drain from the kidney to the bladder due to an obstruction. Contrary to common belief, hydronephrosis is not a disease itself, but is instead is the result of a disease.
Superior vena cava- upper body inferior vena cava
lower body- bother drain into the right atrium
Pi and sigma bonds
Pi is double bonds and sigma is single bonds
