1 Monocot and dicot are short for monocotyledon and dicotyledon. 2  Mono-means one, and monocots have one cotyledon. 3  Di-means two, and dicots have two cotyledons. monocot plant has one cotyledon (scutellum) in its embryo whereas a dicot plant has two cotyledones. 2. A moncot pl â¦ ant has generally isobilateral leaf with parallel venation whereas a diicot plant has dorsiventral leaf with reticulate venation. 3.
The AR-15 was developed as a lighter, 5.56 mm version of the AR-10. The AR in all ArmaLite pattern firearms simply stands for ArmaLite, and can be found on most of the company's firearms: AR-5, a .22 caliber rifle; the AR-7, another .22 caliber; the AR-17 shotgun; the AR-10 rifle; and the AR-24 pistol.
The vast majority of AR barrels fall between the 14.5 military M4 type and the 20. M16 size, with 16 being currently the most popular for civilians. You can buy 14.5 barrels, but for most of us it would require a muzzle device at least 1.5 inches long, and permanently attached, to meet the legal 16 minimum.