<span>Yellow marrow fills the canals of long bones, and red marrow is found in the rounded ends of long bones (for example, the femur). Red marrow is made up of components of blood (red & white blood cells, platelets), while yellow marrow is primarily composed of fat cells.</span>
Q1. Muscles are made of muscle cells that are able to contract. They are only cells in the organisms able to do that. Due to contraction, cells change their shape and length. This enables some organ activity (such as heart, or many other organs that are surrounded by smooth muscles that helps them perform their function) or body movements.
Q2. Striated muscles are called striated because of the series of sarcomeres, basic units of striated muscles. They are made up of long cylindrical fiber and attach to the bones. Contraction of these muscles is voluntary <span>except for the heart muscles</span><span>. During these contractions, the muscle is extended by the action of an antagonist muscle.</span>
Well first, your immune system has two main halves, innate and adaptive... the innate is the line of defense to fight off disease and bacteria, which is made up of anatomical barriers
