Skeletal System

Types of Skeletons

There are 2 types of skeleton.

Endoskeleton Exoskeleton

Example: Humans

Endoskeleton basically means that the skeleton is inside the body. “Endo” meaning within.

Example: Crabs, lobster, Shrimp etc

Exoskeleton means that the skeleton is outside of the body which allows it to have that hard shell. “Exo” meaning outside of the body.

The Human Skeleton

The newborn human body consist of about 300 bones. But when the body reaches certain ages, certain bones start to fuse together which lower the number. When a body reaches adulthood it usually has around 206 bones.

The Human Skull

The skull is mainly to protect the cranium so it does not get damaged. Because damage of the brain could permanently affect you in very harsh ways. But it also has the job of protecting our senses so we are still able to use them.

Osteoporosis

Most common bone disease in the world. The majority of all the people that have it are women

that are the age of 45. Osteoporosis is where the bone is smaller then normal

and is more fragile. This will cause the bones to break easier. Usually the process will be painless up until the point

where the bone breaks.

Type of Joints

Suture joint- a tight joint that sutures crack. Example- the skull

Ball-and-socket joint- a joint sutures itself by a ball on one bone and a socket on the other. Examples- hips-pelvis and arm and shoulder

Hinge joint- a joint that works like a door hinge. Examples- arms and knees

Arthrodial joint-A synovial joint in which the opposing surfaces are nearly planes and in which there is only a slight, gliding motion. Example-hands

Condyal joint-A modified biaxial ball-and-socket joint in which the joint surfaces are elongated or ellipsoidal. Example- arms

Word Definitions

Bone- Mortal remains. Cartilage- Tough connective parts of the body. Joint- Area where adjacent bones meet or articulate. Marrow- The spinal chord. Ossification- The natural process of bone formation. Osteocyte- a branched cell embedded in the matrix of bone tissue. Pectoral Girdle- A bony cartilaginous structure in vertebrates. Humerus- The long bone or forelimb extending from the shoulder

elbow. Ulna-The bone extending from the elbow to the wrist on the side

opposite to the thumb in humans. Radius- A long, prismatic, slightly curved bone, the shorter and

thicker of the two forearm bones, located on the lateral side of the ulna.

Carpals- A bone of the carpus. Metacarpals- Any of the bones of the metacarpus

Word Definitions (Continued)

Phalanges- Any of the bones of the metacarpus.Skull- The bony or cartilaginous framework of the head of vertebrates, made

up of the bones of the braincase and face; cranium. Mandible- The lower jaw of a vertebrate animal. Sternum- A long flat bone in most vertebrates that is situated along the

ventral midline of the thorax and articulates with the ribs. The manubrium of the sternum articulates with the clavicles in humans and certain other vertebrates.

Rib Cage-The enclosing structure formed by the ribs and the bones to which they are attached.

Vertebral Column- the series of vertebrae forming the axis of the skeleton and protecting the spinal cord.

Pelvic Girdle- A bony or cartilaginous structure in vertebrates, attached to and supporting the hind limbs or fins. Also called pelvic arch.

Femur- A bone of the leg situated between the pelvis and knee in humans. It is the largest and strongest bone in the body.

Word Definitions (Continued)

Patella- A flat triangular bone located at the front of the knee joint. Also called kneecap.

Tibia- The inner and larger of the two bones of the lower human leg, extending from the knee to the ankle.

Fibula- The outer and narrower of two bones of the human lower leg, extending from the knee to the ankle.

Tarsal- Of or relating to the tarsus of the eyelid: the tarsal ligaments.

Metatarsals- Any of the bones of the metatarsus