Cell membranes are mostly made up of lipids (fats)
<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>
Smilus dramaticus: All of the Duchotomous keys one smiles :)
.Smilus upsettus
Smilus saddus
Smilus winkus
Smilus Saddest
Smilus piratus
Smilus valentinus
Smilus suprisus
Smilus toothyus
Smilus traditionalis
Carbon and nitrogen and an important element of living things. Nitrogen is a major component of DNA and amino acids while carbon can be found in almost all biomolecules. These elements, therefore, need to be renewed and recycled as they are utilized by ecosystems that is ever dynamic.