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.
AR-15 barrel length. The AR-15 is perhaps the most popular carbine in America. It's commonly compared to the AK-47 despite the vast number of differences between the two weapons. While AR-15s are modular weapons meaning many of the parts can easily be replaced or upgraded, barrel length is often left unchanged at 16 inches. There are many reasons to deviate from the standard 16 barrel length. Many M16 rifles were built with a 20 barrel that gave it a little better accuracy. Some AR rifles are available with 20, 18, and 14.7 barrels are also become popular.