SCIENCE 2ND QT TEST - SKELETEAL SYSTEM

• The skeletal system provides the structural framework for the body and protects internal organs such as heart, lungs, brains, and many more.
• The framework in houses is similar with the skeletal system.
• The skeletal system consists of two divisions: the axial and the appendicular skeleton.
• The axial skeleton includes the skull, the vertebral column, the ribs, and the sternum.
• The appendicular skeleton includes the bones of the shoulders, arms, hands, hips, legs, and feet.
• The human skeleton consists of blank bones: long, short, flat, and irregular.
• Long bones are found in the limbs like arms and legs.
• Short bones are found in the wrists and ankles.
• Flat bones are usually found in the shoulder blades and skull.
• Irregular bones are found in the face and vertebrae.
• When a baby is born, their bones are softer and more flexible because they consist mostly of cartilage.
• Cartilage is a smooth, elastic bone-like tissue found in the nose and joints.
• As a child grows up, some bones or cartilages join together and form a new bone.
• An infant has 350 bones, a child has 208 bones, and a normal adult has 206 bones.
• The skull is the bone in the hand and consists of blank cranium and blank facial bone.
• The cranium is made of blank eight bones that join together to form a rigid case that protects the brain.
• The mandible or jawbone protects the teeth.
• The spinal column and ribs are the bones at the back from the neck going down to the middle part of the hip bone.
• The spinal column protects a very delicate organ called spinal cord.
• The back bone or spinal column is made up of blank regular bones called vertebrae.
• Vertebrae are arranged on top of the other and move over each other slightly.
• There are 33 vertebrae in a spinal column of a child as the child grows up, the last seven bones joined together and form just two bones, so the number of vertebrae of an adult become 26.
• The ribs are the bones at the side of the chest that protect the lungs and the heart.
• There are 12 pairs of ribs, the upper-70s are called true ribs because they are connected to the breastbone or sternum, and the lower five pairs are called false ribs.
• Of the five pairs of false ribs, the upper three pairs are connected to the breastbone, while the last two pairs are not, these ribs are called floating ribs.
• The collarbone and shoulder are the bones at the shoulder.