Answer:D
Explanation: The pulmonary air sacs of birds only permit a unidirectional flow of air through the lungs. Unidirectional flow means that air is inhale and exhale through one trachea alternatively. This means the bird lungs only receive largely fresh air which has a high oxygen content during inhalation and do not receive fresh during exhalation. While air flow bidirectional in mammals.
Answer:
Answer is B. Priapism.
Explanation:
Corpus spongiosum are the three cylinders encased in the bucks fascia. They run through the glass and shaft of the penis, and during erection, they contain almost 85-90% of theology volume.
Priapism can be described as persistent erection of the penis, which is caused by excessive blood flow to the penis or when blood is trapped inside the penis blood chambers I. e, corpus spongiosum.
Priapism can be of two types, they are
1. High- flow Priapism : this is caused when the artery supplying blood to the penis is damaged, thereby, causing it to be oversupplied with oxygenated blood. This type is not painful and can be treated by adopting cold therapy, the use of ice packs.
2. Low-flow Priapism : This occurs when old blood is trapped inside the penis blood chambers. This type is very painful and require urgent medical attention.
Note that, the second type of priapism,low-flow priapism, is caused in the case of a sickled-cell person, because the shape of the blood cell can easily trap blood in the penis.
