Skeletal+System

=**Period 1 Skeletal System**=

Cheryl Faux Maddie Wood Celeste Erin Smith

The Skeletal System The Skeletal system is all the bones in the body and the tissues, tendons, ligaments, cartilage, that connect them together. To get a good overview of the Skeletal System here is a funny 'ol video: []

Function of the Skeletal System

> Think of the skeleton as a car, it’s the framework of the body. It supports the softer tissues and provides points of attachment for most muscles. > The skeleton helps to reduce injury to many of the body’s internal organs. For example, cranial bones protect the brain, vertebrae protect the spinal cord, and the ribcage protects the heart and lungs. > A lot of skeletal muscles are attached to bones so whenever those muscles move, it causes the bones to move as well. > Bone tissues store several minerals, including calcium (Ca) and phosphorus (P). > The red bone marrow inside some larger bones help produce blood cells.
 * ** Support
 * Protection
 * Movement
 * Storage of Minerals
 * Production of Blood Cells

Types of Bones Long bones are greater in length than they are in width and consist of a shaft and numerous ending (extremities). Examples include femur, tibia, fibula, humerus, ulna, and radius. Short bones are cube-shaped and are approximately equal in width and length. Examples include wrist and ankle bones. <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Flat bones are thin and flat in shape and provide protection for most muscle attachments are. Examples include cranial bones (protecting the brain), the sternum and ribs (protecting organs), and the scapulae (shoulder blades). <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Irregular bones have complicated shapes due to the fact that some of their functions that they provide for the body. Examples include vertebras and some facial bones. <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Sesamoid bones develop in dome tendons where there are is a lot of friction and tension. Examples soles of the feet, palms of the hand and the patella (kneecaps). <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Sutural bones are small bones located in the sutural joints in the cranium bones. The number of sutural bones varies by person.
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Long Bones
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Short Bones
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Flat Bones
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Irregular Bones
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Sesamoid Bones
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Sutural Bones

<span style="color: #00a9ff; display: block; font-family: Verdana,Geneva,sans-serif; font-size: 170%; text-align: center;">Structure of Bones
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Compact-tissue forms the outer shell of the bone. It consists of extremely hard bone mass.
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">Cancellous (known as spongy)- tissue is located beneath the compact bone and consists of a meshwork of bony bars.

<span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">The diagram to the left shows the basic components of a long bone:
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">articulartory (also known as 'articular') cartilage;
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">spongy bone;
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">bone marrow;
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">endosteum;
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">compact bone;
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">periosteum;
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">medullary cavity, and
 * <span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif;">a blood vessel (indicating blood supply and circulation within bones).

<span style="color: #00a9ff; font-family: Verdana,Geneva,sans-serif; font-size: 120%;">Here's a cool, internactive quiz over the structure of the skeletal system for review: []

How the Skeletal System works with body systems <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">**Integumentary system**- supports skin so that our body does not sag- allows us to stand

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">**Muscular System**- gives skeletal muscle something to pull against so skeletal muscle can move and gives support to body- and works as a lever for muscles to produce movement

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">**Circulatory System**- protects the heart and bone marrow produces red blood cells

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">**Urinary System**- protects the kidneys

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">**Nervous System**- protects the brain and spinal chord

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">**Digestive System**- protects the mouth, esophagus, stomach, pancreas, liver, and gall bladder- leads food safely through- allows mouth to open and air to flow sown the trachea

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">**Respiratory System**- protects trachea, vocal chords and diaphragm <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">


 * Review Questions: **

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">For questions 1-4 use the following choices:

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">a.Hydrostatic Skeleton b.Exoskeleton c.Endoskeleton d.Cuticle


 * <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">1.The calcium carbonate shell of a mollusk is an example of what? _ **
 * <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">2. The jointed exoskeleton of arthropods is a _. **
 * <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">3. This consists of fluid held under pressure. _ **
 * <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">4. Skeleton of most cnidarians, flatworms, nematodes, and annelids. _ **

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">a.Is hardened with organic compounds that cross-link the proteins of the exoskeleton <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">b.Has little cross-linking of proteins <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">c.Sheds its exoskeleton to produce a larger one <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">d.None. The cuticle’s activity is uniform throughout the arthropod.
 * <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">5.An arthopod’s cuticle when protection is most important **

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">a.Hard spicules <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">b.An inward cuticle <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">c.Ossicles <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">d.Soft Tissue
 * <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">6.An echinoderm’s endoskeleton consists of: **

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">a.Cartilage <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">b.Bone <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">c.Soft Tissue <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">d.Both a and b
 * <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">7.Chordates’ endoskeleton consists of: **

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">a.One main part is the skull, backbone, and rib cage and the other is the part of the skeleton that anchor the appendages <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">b.On position <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">c.On necessity to the organism <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">d.All of the above are taken into consideration
 * <span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">8.On what basis is the vertebrate skeleton divided, accord to anatomists? **

=** Enzymes in the Skeletal System **= v Enzymes in the Bone v Enzymes in the Skeletal Muscle
 * alkaline phosphatase
 * an enzyme that has a role in the mineralization of bone
 * Found in the Osteoblast
 * immature bone cells that eventually become entrapped in the bone matrix to become osteocytes- the mature bone cell
 * Aldolase
 * protein (called an enzyme) that helps break down certain sugars into energy
 * Damage to the skeletal muscles creates high levels of Aldolase, particularly in Musclar Dystrophy –a disease that causes muscle weakness and loss of muscle tissue, which gets worse over time
 * Creatine Phosphokinase (CPK or CK)
 * catalyzes the reversible transfer of phosphate groups between creatine and phosphocreatine as well as between ATP and ADP
 * enters the blood rapidly following damage to muscle cell

= Regulation in the Skeletal System = v Calcium and Phosphorus
 * Calcium regulation is needed for bone function
 * The body regulates calcium through the parathyroid hormone (PTH) and vitamin D, and to a lesser extent calcitonin.
 * PTH
 * Increases the amount of calcium in the blood through the release of PTH and the removal of calcium from the blood
 * Decreasing the amount of calcium releases less PTH
 * Vitamin DHomeostasis
 * Helps to form and maintain strong, healthy bones by increasing the amount of dietary calcium absorbed by the intestines
 * Stops the parathyroid gland from secreting parathyroid hormones, which would increase the levels of calcium in the blood (this can become dangerous if too much calcium is in the blood)


 * Calcitonin
 * Increases osteoblast activity
 * Released by the thyroid gland
 * Parathyroid HormoneAs long as calcitonin and parathyroid hormone functions normally, bone mass stays the same (homeostatic state of the bone)
 * Increases osteoclast activity
 * Released by the parathyroid glands
 * If it goes out of balance
 * Build too much bone or
 * Lose bone mass
 * Leads to osteoporosis
 * The skeletal system stores a limited amount of minerals
 * When bones are exposed
 * They take in a lot of minerals to become harder
 * Minerals and hormones
 * Minerals
 * Vitamins A,D,C
 * Dietary Calcium
 * Hormones
 * Thyroid hormones
 * thyroxine (T4) and triiodothyronine (T3), are tyrosine-based hormones produced by the thyroid gland primarily responsible for regulation of metabolism
 * Parathyroid hormone
 * parathormone or parathyrin, is secreted by the chief cells of the parathyroid glands as a polypeptide containing 84 amino acids.
 * Calcitonin
 * (also known as thyrocalcitonin) is a 32-amino acid linear polypeptide hormone that is produced in humans primarily by the parafollicular cells (also known as C-cells) of the thyroid
 * And calcitriol
 * a form of vitamin D that is used to treat and prevent low levels of calcium in the blood of patients whose kidneys or parathyroid glands (glands in the neck that release natural substances to control the amount of calcium in the blood) are not working normally
 * a form of vitamin D that is used to treat and prevent low levels of calcium in the blood of patients whose kidneys or parathyroid glands (glands in the neck that release natural substances to control the amount of calcium in the blood) are not working normally

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">**Answers**: 1. b 2. d 3. a 4. a 5. b 6. c 7. d 8. d

<span style="color: #07b607; font-family: Tahoma,Geneva,sans-serif; font-size: 110%;">Here is a skeletal system rap to finish you guys off!

http://vimeo.com/39230688