<span>Penile shaft
</span>During erection, blood<span> flows into the spaces, causing distention and elevation of the penis. The amount of blood entering the penis can be increased by physical or psychological stimulation. As blood enters, there is a temporary reduction in the rate and volume of blood leaving the penis. The arteries carrying blood to the penis dilate; this, in turn, causes tissue expansion. The veins leading from the penis have funnel-shaped valves that reduce the outflow of blood. As the erectile tissue begins to enlarge, the additional pressure causes the veins to be squeezed against the surrounding fibrous tissue, and this further diminishes the outflow of blood. Essentially, blood becomes temporarily trapped in the organ.</span>
Answer:
B. Sternum
Explanation:
The sternum (or breastbone) is a flat bone in the thorax's anterior area. It has a 'T' shape and is located in the center of the chest. The sternum, which is part of the bony thoracic wall, protects the internal thoracic viscera, such as the heart, lungs, and oesophagus.
Here is a picture from the internet.
The answer is B) metaphase
