hello everyone and this Anatomy lesson I'm going to talk about the different types of bones found in the human skeleton and as you probably noticed bones come in different shapes so an animus like to classify them into different categories and we have four major categories of bones long bones short bones flat bones and irregular bones and we also have two minor categories of bones which are the sesamoid bones and the sutural bones first I'll talk about long bones which are the most common type of bone found in the body and these bones can vary in length but the key characteristic that you want to remember is that they are always going to be longer than they are wide and these bones are going to have a shaft made primarily of compact bone and too bulky ends which often contain spongy bone now the average adult skeleton has 206 bones and there are going to be 90 long bones in the average adult skeleton consisting mostly of bones from the upper and lower extremities such as a humerus radius the femur and so forth as well as those clavicle bones next we have short bones which have approximately the same length and width which gives them a cue block appearance short bones consist mostly of spongy bone that is covered by a thin layer of compact bone and there are 28 short bones in the adult skeleton consisting of the tarsals and most of the carpal bones of the wrist we also have sesamoid bones which some anatomist like to classify as a special subset of short bones and these are going to be embedded in tendons and the word sesamoid sounds kind of like sesame seed and that's because these seeds shaped bones get their name from a greek word that literally means resembling a sesame seed there are four sesamoid bones in the adult skeleton you're gonna have two patella bones which is your kneecap bone and you're also gonna have two paese form bones which are the carpal bones and sometimes sesamoid bones can form on the tarsal or maida tarsal or even the yuccas bone in the ear but this can vary from person to person next we have flat bones which provide protection to those vital organs and as the name suggests they are mostly flat and curved and they have a thin plate lock formation and they contain a layer of spongy bone covered by a thin layer of compact bone and some flat bones do look a little irregular so it can be confusing for example the scapula bone is technically a flat bone but it does contain that spine that acromion and that coracoid process that does make it look somewhat irregular but it's still classified as a flat bone and there are 36 flat bones in the adult skeleton including some of the skull bones as well as the sternum and the ribs and while I'm talking about those flat bones of the skull it's a good time to mention another minor category of Bones called sutural bones or wormy and bones and if you notice the sutures on most of these skull bones that can be very jagged and irregular and sometimes those little jagged suture joints can form a little independent bone and that's all a suture old bony is and they don't actually serve a functional physical purpose but they can be a marker for some diseases and then finally we have the last major category of bones which are the irregular bones and these come in various funky shapes and sizes and they don't fit in any other of the bum categories so they put them in their own category and these also consists of a layer of spongy bone covered by a thin layer of compact bone and there are 48 irregular bones in the adult skeleton including the hip bones the vertebra the hyoid bone and some of your skull bones now some anatomist will disagree on the exact number of bone categories and whether this bone should be in this category or that category so I would recommend you double-check your textbook to find out what your professor wants you to learn but generally speaking that should help you understand the different types of bones and we have a free quiz on our website that you can check in the description below to help you test your knowledge on this topic also we have a whole playlist of Anatomy videos so make sure to check that out thank you so much for watching and please subscribe