Identify and illustrate the two subdivisions of the skeleton the axial and appendicular
Axial Skeleton
The axial skeleton consists of the 80 bones along the central axis of the human body. It is composed of three parts; the human skull, the rib cage and the vertebral column. its main purpose is to protect the inner organs form harm and being dameged.
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The Skull
The Skull The skull, or cranium-sound, could be thought of as the most important structure in your skeleton, especially considering that it houses your brain. Your skull provides the framework for most of your sensory organs, such as eyes, ears, tongue, nose, and some skin.
Your skull is made up of 22 cranial or facial bones, plus the three in each ear. As a baby you have more. Most are fixed joints separated by cartilage as a baby, but fuse together a later as you grow. Once fused, they are locked together, forming an immovable joints, called a suture-sound.
Your skull is made up of 22 cranial or facial bones, plus the three in each ear. As a baby you have more. Most are fixed joints separated by cartilage as a baby, but fuse together a later as you grow. Once fused, they are locked together, forming an immovable joints, called a suture-sound.
The Backbone
The backbone, or vertebral or spinal column, though called a "bone", is really a flexible structure made of 26 bones. As a baby, you have 33 vertebrae, or back bones, but the lower four fuse to form the coccyx-sound, and the next lower five fuse to become the sacrum. The backbone serves several important functions itself. It provides structure from which all other upper body structures branch, and it protects the spinal nerve, which is the "highway" that all the information your brain sends to your body travels. If the spinal column were to be damaging, also damaging the spinal nerve, it would be like the highway collapsed, and all landmarks past that point could no longer be visited, causing paralyzation from that point in your back and down.
The backbone is approximately 28 inches, or 70 cm, long, and is separated into five regions. The last two, the coccyx and sacrum-sound, are separated by the fused vertebrae. The remaining three are distinguished mostly by concavity with respect to your front. The remaining regions are: the cervical-sound curvature made of 7 vertebrae and concave; the thoracic-sound region made of 12 vertebrae and convex, and the lumbar-sound curvature made of 5 vertebrae and concave
The backbone is approximately 28 inches, or 70 cm, long, and is separated into five regions. The last two, the coccyx and sacrum-sound, are separated by the fused vertebrae. The remaining three are distinguished mostly by concavity with respect to your front. The remaining regions are: the cervical-sound curvature made of 7 vertebrae and concave; the thoracic-sound region made of 12 vertebrae and convex, and the lumbar-sound curvature made of 5 vertebrae and concave
The Rib Cage
The bony thorax is basically your chest, comprising your breast bone and ribs. Your breast bone, or sternum-sound, is around 6 inches (15 cm) tall, spanning about half the length of your ribs.
You have twelve ribs, forming the structure for your chest. One primary purpose of your ribs is to protect your lungs are heart. Except for your floating ribs, each rib connects to the sternum by cartilage on the tips. Your top seven ribs are called true ribs because they connect directly to the sternum. The next four ribs are called false ribs because they attach to the sternum so indirectly if at all. If they do not connect to the sternum, they do connect to upper cartilage for support. The last two ribs are called floating ribs because they do not connect to the sternum or any other support on the end.
You have twelve ribs, forming the structure for your chest. One primary purpose of your ribs is to protect your lungs are heart. Except for your floating ribs, each rib connects to the sternum by cartilage on the tips. Your top seven ribs are called true ribs because they connect directly to the sternum. The next four ribs are called false ribs because they attach to the sternum so indirectly if at all. If they do not connect to the sternum, they do connect to upper cartilage for support. The last two ribs are called floating ribs because they do not connect to the sternum or any other support on the end.
Appendicular Skeleton
The appendicular skeleton refers to your arms and legs. They are called appendicular (from "append") because they are attached by girdles, which bridge each with the main body, as if they had been appended after the main body was formed. These girdles give these appendages a remarkable range of movement unique from anywhere else in the body. Obviously the arms are the same allowing symmetry, and the legs are too. But ignoring size and shape, and instead focusing on joints and relative placement, your arms and legs are the same, too.
The Upper Appendages
The Upper Appendages The main purpose of the arms is to do work. They are lighter and are made to focus on detail.
In your upper arm is your humerus which connects to the girdle as a ball-and-socket joint. It connects to your forearm with a hinge joint. The forearm is really two bones, the radius-sound and the ulna-sound. The ulna is the bone that joins with the humerus-sound in the elbow joint. Having two bones instead of one allows for a wide range of twisting of the wrists.
The Hand The carpus, or wrist of the hand, is made of eight small bones in two irregular rows connect with gliding joints. These eight bones give your wrist the flexibility it has.
Five metacarples-sound extend from the carpus, covered with skin, form the palm. Looking at just the skeleton, they look like the base of really long fingers. The tips of these bones are the knuckles you see when you make a fist. At the beginning of this, the skeletal, topic, one of the characteristics that make the human skeleton unique is the opposable thumb. The first metacarpal, the thumb base, is jointed differently that the rest of the metacarples. They lay in a single plane, while the thumb metacarpal is connected with a saddle joint, giving it a range of movement. This is what makes grasping things as easy as it is.
The rest of the hand comprises the phalanges, what we see as the fingers. Each finger has three phalanges, except for the thumb, which has two.
In your upper arm is your humerus which connects to the girdle as a ball-and-socket joint. It connects to your forearm with a hinge joint. The forearm is really two bones, the radius-sound and the ulna-sound. The ulna is the bone that joins with the humerus-sound in the elbow joint. Having two bones instead of one allows for a wide range of twisting of the wrists.
The Hand The carpus, or wrist of the hand, is made of eight small bones in two irregular rows connect with gliding joints. These eight bones give your wrist the flexibility it has.
Five metacarples-sound extend from the carpus, covered with skin, form the palm. Looking at just the skeleton, they look like the base of really long fingers. The tips of these bones are the knuckles you see when you make a fist. At the beginning of this, the skeletal, topic, one of the characteristics that make the human skeleton unique is the opposable thumb. The first metacarpal, the thumb base, is jointed differently that the rest of the metacarples. They lay in a single plane, while the thumb metacarpal is connected with a saddle joint, giving it a range of movement. This is what makes grasping things as easy as it is.
The rest of the hand comprises the phalanges, what we see as the fingers. Each finger has three phalanges, except for the thumb, which has two.
The lower Appendages
The Pelvic (Hip) Girdle. The pelvic girdle consists of two large, sturdy hip bones. Each hip bone consists of three fused bones namely the ilium, ischium and the pubis. The ilium is the largest of the three and forms the upper part of the hip bones. The sacrum fits like a wedge posteriorly between the two hip bones. The sacrum has a large, flat articular surface on each side for articulation with the ilia. The ischium forms the inferior part of the hip bone and the pubis the central in front. The two pubic bones are attached in the middle, on the front side by a symphysis which consists of fibrocartilage and ligaments, the pubic symphysis. The two hip bones and the sacrum form a complete bony ring, the pelvis . On the outer side of the point where the fused bones meet, there is a deep hip socket into which the head of the femur fits.
The pelvic girdle forms a strong support for the attachment of the limbs. Strong muscles of the back, the legs and the buttocks are attached to it. It protects some of the internal organs. In females it forms a strong basin-like structure for supporting and protecting the developing foetus during child-bearing.
The Pelvic Girdle.
The Upper Leg or Thigh
The upper leg has a single long bone, the femur and is the longest bone in the body. The head of the femur is turned slightly inwards and has a large, rounded portion which articulates in the acetubulum, forming a ball-and-socket joint. At its distal end, the femur widens to form two large knobs (condyles) which form the hinged knee joint with the main long bone (tibia) of the lower leg. On the anterior side of these two condyles, there is an articular surface against which the kneecap (patella) slides. The patella is a small, triangular, flat bone which develops on the tendon of the thigh muscle and is attached by ligaments to the tibia. This enables movement in the knee joint.
The Lower Leg
The two bones of the lower leg are the tibia (shinbone) in front and the fibula behind. The tibia is the larger of the two and extends from the knee to the ankle. The upper end of the tibia has two articulating facets into which the condyles of the femur fit to form the knee joint. The lower end of the tibia articulates with one of the tarsals to form the ankle joint. The fibula is smaller than the tibia and is situated on the outside and slightly behind it. The upper end articulates with the tibia but does not form part of the knee joint. The lower end forms part of the ankle joint.
The Ankle
There are seven short, thick tarsal bones, the largest of which is the heel bone (calcaneum), which presses firmly onto the ground when one stands, walks or runs. The calf muscles are attached to the calcenum, allowing the heel to be lifted during locomotion.
The Arch of the Foot
The arch is formed partly by some of the tarsals but mainly by the five long metatarsals, which extends from the tarsals to the toes. The arch is modified for receiving the weight of the body.
The Toes
There are fourteen short phalanges in the toes of each foot. The big toe has two phalanges and the other toes have three in each.
The pelvic girdle forms a strong support for the attachment of the limbs. Strong muscles of the back, the legs and the buttocks are attached to it. It protects some of the internal organs. In females it forms a strong basin-like structure for supporting and protecting the developing foetus during child-bearing.
The Pelvic Girdle.
- The Lower Limbs or Legs.
The Upper Leg or Thigh
The upper leg has a single long bone, the femur and is the longest bone in the body. The head of the femur is turned slightly inwards and has a large, rounded portion which articulates in the acetubulum, forming a ball-and-socket joint. At its distal end, the femur widens to form two large knobs (condyles) which form the hinged knee joint with the main long bone (tibia) of the lower leg. On the anterior side of these two condyles, there is an articular surface against which the kneecap (patella) slides. The patella is a small, triangular, flat bone which develops on the tendon of the thigh muscle and is attached by ligaments to the tibia. This enables movement in the knee joint.
The Lower Leg
The two bones of the lower leg are the tibia (shinbone) in front and the fibula behind. The tibia is the larger of the two and extends from the knee to the ankle. The upper end of the tibia has two articulating facets into which the condyles of the femur fit to form the knee joint. The lower end of the tibia articulates with one of the tarsals to form the ankle joint. The fibula is smaller than the tibia and is situated on the outside and slightly behind it. The upper end articulates with the tibia but does not form part of the knee joint. The lower end forms part of the ankle joint.
The Ankle
There are seven short, thick tarsal bones, the largest of which is the heel bone (calcaneum), which presses firmly onto the ground when one stands, walks or runs. The calf muscles are attached to the calcenum, allowing the heel to be lifted during locomotion.
The Arch of the Foot
The arch is formed partly by some of the tarsals but mainly by the five long metatarsals, which extends from the tarsals to the toes. The arch is modified for receiving the weight of the body.
The Toes
There are fourteen short phalanges in the toes of each foot. The big toe has two phalanges and the other toes have three in each.
What are the three main functions of the skeleton
The entire frame of our body is made of bones and is called the skeleton. It is the name given to the framework of bones that holds up the rest of our body. All the bones of our body are connected to each other. The places where the bones meet are called joints.
The end of each bone is covered by a tough, smooth shiny substance called cartilage. The ends of each bone are further separated by a thin film of slippery fluid that works like oil in a car. It prevents the,bones from bumping against each other when you move. Our bones are held together by strong elastic-like bands called ligaments.
Our skeleton is very important to us. It has three main functions:
1. It protects the important organs inside our body such as the brain, the heart and the lungs. The bony part of the head is called skull. The bones around our chest form a rib cage.
2. The skeleton supports our body and gives it shape. It is like a container for all the internal organs and tissues of the body. Can you imagine what would happen to your body if you had no bones?
The skeleton allows us to move. Our muscles are attached to our bones. When our muscles move, they move the bones, and thus we move. There would be little or movement possible without the help of the skeletal system.
When human beings are born, their skeleton has around 350 bones. By the time they become adults, they have around 206 bones. This is because, as we grow, some of the bones fuse together to form one bone.
The end of each bone is covered by a tough, smooth shiny substance called cartilage. The ends of each bone are further separated by a thin film of slippery fluid that works like oil in a car. It prevents the,bones from bumping against each other when you move. Our bones are held together by strong elastic-like bands called ligaments.
Our skeleton is very important to us. It has three main functions:
1. It protects the important organs inside our body such as the brain, the heart and the lungs. The bony part of the head is called skull. The bones around our chest form a rib cage.
2. The skeleton supports our body and gives it shape. It is like a container for all the internal organs and tissues of the body. Can you imagine what would happen to your body if you had no bones?
The skeleton allows us to move. Our muscles are attached to our bones. When our muscles move, they move the bones, and thus we move. There would be little or movement possible without the help of the skeletal system.
When human beings are born, their skeleton has around 350 bones. By the time they become adults, they have around 206 bones. This is because, as we grow, some of the bones fuse together to form one bone.
Name, describe and illustrate the main types of bones
Long Bones
Long Bone:
Long Bones are typically longer than wider. As a rule to remember them is that they have a shaft and two heads at both ends. these bones are usually made up of compact bone. this includes all the bones in the limps except the patella wrist and ankle are long bones.
Long Bones are typically longer than wider. As a rule to remember them is that they have a shaft and two heads at both ends. these bones are usually made up of compact bone. this includes all the bones in the limps except the patella wrist and ankle are long bones.
Short Bones
Short Bone:
short bones are genereally cube shaped and contain mostly spongy bone. the bones of the wrist and ankle are short bones. Sesamoid bones which form in tendonsare special type of short bone. the best known example is the patella.
short bones are genereally cube shaped and contain mostly spongy bone. the bones of the wrist and ankle are short bones. Sesamoid bones which form in tendonsare special type of short bone. the best known example is the patella.
Flat and Irregular Bones
flat bones are thin flattened and usually curved. they have two thin layers of compact bone sandwiching a layer of spongy bone between them. most bones of the skull, ribs and sternum are flat bones. bones that dont fit in the precedong categories are called irregular bones. the vertebrae which make up the spinal column and the hip bones fall into gourp.