Who doesn’t love quizzes? When it comes to learning anatomy, they’re absolutely perfect for learning a topic from scratch, or even advancing your current knowledge levels. In the musculoskeletal system, ligaments stabilize the articulating bones and reinforce the joints. Depending on their anatomic position relative to the joint capsule, ligaments are classified into: The brain is made up of three main subparts: the cerebrum, the cerebellum, and the brainstem. Within these areas, there are several key components of the brain that, together with the spinal cord, comprise the central nervous system.

As an individual ages, the joint tissues become less resilient to wear and tear and start to degenerate. This degeneration manifest as swelling, pain, and often-times, loss of mobility of joints. Changes occur in both joint soft tissues and the articulating bones, a condition called osteoarthritis. A more serious form of disease is called rheumatoid arthritis. The latter is an autoimmune disease wherein the body produces antibodies against joint tissues causing chronic inflammation resulting in severe joint damage, pain and immobility. The main function of the extensor hallucis longus is extension of the big toe (hallux) at metatarsophalangeal joints. In addition, the muscle can act on the ankle joint and assist the other muscles of the anterior group to produce dorsiflexion of the foot. The gastrocnemius is innervated by the tibial nerve (S1, S2). Its blood supply is mainly derived from the lateral and medial sural branches of the popliteal artery, with contributions from the superior genicular arteries.Cell-to-cell communication is largely facilitated via gap junctions which are located close to openings in the basement membrane, allowing the regulation and propagation of contractile signals across the smooth muscle tissue. Skeletal muscles are named based on many different factors, including their location, origin and insertion, number of origins, shape, size, direction, and function. Mons pubis: The mons pubis is the rounded, fleshy area on the front of the pelvic bone (the lower belly area) where pubic hair usually grows.

Long bones have a tubular shape, with a longer longitudinal and a shorter transverse diameter. They are composed mostly of compact bone, while the spongy bone and bony marrow fill the ends of the bones. Examples of long bones include the humerus, ulna, tibia and clavicle. All content published on Kenhub is reviewed by medical and anatomy experts. The information we provide is grounded on academic literature and peer-reviewed research. Kenhub does not provide medical advice. You can learn more about our content creation and review standards by reading our content quality guidelines. The skeletal muscles of the human body are organized into four groups for every region of the body:

Myofilament Components

Muscles move by shortening their length, pulling on tendons, and moving bones closer to each other. One of the bones is pulled towards the other bone, which remains stationary. The place on the stationary bone that is connected via tendons to the muscle is called the origin. The place on the moving bone that is connected to the muscle via tendons is called the insertion. The belly of the muscle is the fleshy part of the muscle in between the tendons that does the actual contraction. Names of Skeletal Muscles The kidneys also produce urine when they remove waste from the blood. Urine flows out of the kidneys through the ureters, then down to the urinary bladder. Myasthenia gravis (MG): This autoimmune disease prevents muscles and nerves from communicating as they should. It leads to severe muscle weakness and fatigue. MG can make it difficult to move, walk, speak, chew, see, hold your head up or keep your eyelids open. It can even lead to severe breathing problems. Another function related to movement is the movement of substances inside the body. The cardiac and visceral muscles are primarily responsible for transporting substances like blood or food from one part of the body to another. When the body drifts off into sleep, it undergoes physiological changes related to body temperature, breathing rate and muscular tone. Hypnic jerks may be the result of muscle changes. Another theory suggests that the transition from the waking to the sleeping state signals the body to relax. But the brain may interpret the relaxation as a sign of falling and then signal the arms and legs to wake up. Electroencephalogram studies have shown sleep starts affect almost 10 percent of the population regularly, 80 percent occasionally, and another 10 percent rarely.