Their smooth muscle is less than arteries. Elastic fibers provide recoil which is what you need in arteries to propel the blood forward. Veins lack these which is why large amounts of blood can be stored in them without the walls providing any sort of recoil and keeping pressure low.elative to the walls of arteries, the veins' walls are thinner, because the pressure of the blood in the veins is much lower; so low in fact, that valves are required to prev â¦ ent blood in the veins flowing backwards.
The plant Agave americana, which is sometimes called American aloe, belongs to the Asparagaceae, a different family. The genus is native to tropical and southern Africa, Madagascar, Jordan, the Arabian Peninsula, and various islands in the Indian Ocean (Mauritius, Reunion, RÃ©union, comoros.). etc
Sand and Gravel. All members of the Aloe genus require sandy or gravelly soil with very good drainage to reduce the risk of root rot and nutritional deficiencies. When planted in containers, aloe vera plants do well in a mixture of commercial potting mix with extra sand, granite grit or perlite added.They can also be planted in potting soil meant specifically for cactuses. When planting aloe vera outdoors, look for a sandy spot that dries out completely after rainfall.se mulch and plastic only with great care around aloes. According to Purdue University, aloe vera plants grown under black polyethylene mulch produced more gel per leaf than plants grown on bare soil, but the appearance and size of the aloes did not change.