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1. Human Skeleton Study Guide

Continued From Above. Calcium, iron, and energy in the form of fat. Finally, the skeleton grows throughout childhood and provides a framework for the rest of the body to grow along with it. Skeletal System Anatomy The skeletal system in an adult body is made up of 206 individual bones. These bones are arranged into two major divisions: the axial skeleton and the appendicular skeleton. The axial skeleton runs along the body’s midline axis and is made up of 80 bones in the following regions:. Skull.

Hyoid. Auditory ossicles. Ribs. Sternum. Vertebral column The appendicular skeleton is made up of 126 bones in the folowing regions:. Upper limbs.

Lower limbs. Pelvic girdle. Pectoral (shoulder) girdle Skull The is composed of 22 bones that are fused together except for the mandible. These 21 fused bones are separate in children to allow the skull and brain to grow, but fuse to give added strength and protection as an adult. The remains as a movable jaw bone and forms the only movable joint in the skull with the.

The bones of the superior portion of the skull are known as the cranium and protect the brain from damage. The bones of the inferior and anterior portion of the skull are known as facial bones and support the eyes, nose, and mouth. Hyoid and Auditory Ossicles The is a small, U-shaped bone found just inferior to the mandible. The hyoid is the only bone in the body that does not form a joint with any other bone—it is a floating bone.

The hyoid’s function is to help hold the open and to form a bony connection for the. The malleus, incus, and stapes—known collectively as the —are the smallest bones in the body. Found in a small cavity inside of the temporal bone, they serve to transmit and amplify sound from the eardrum to the inner ear. Vertebrae Twenty-six vertebrae form the of the human body. They are named by region:. (neck) - 7 vertebrae. (chest) - 12 vertebrae.

(lower back) - 5 vertebrae. 1 vertebra. (tailbone) - 1 vertebra With the exception of the singular sacrum and coccyx, each vertebra is named for the first letter of its region and its position along the superior-inferior axis. For example, the most superior thoracic vertebra is called T1 and the most inferior is called T12. Ribs and Sternum The sternum, or breastbone, is a thin, knife-shaped bone located along the midline of the anterior side of the.

The sternum connects to the ribs by thin bands of cartilage called the costal cartilage. There are 12 pairs of ribs that together with the sternum form the ribcage of the thoracic region. The first seven ribs are known as “true ribs” because they connect the thoracic vertebrae directly to the sternum through their own band of costal cartilage. Ribs 8, 9, and 10 all connect to the sternum through cartilage that is connected to the cartilage of the seventh rib, so we consider these to be “false ribs.” Ribs 11 and 12 are also false ribs, but are also considered to be “floating ribs” because they do not have any cartilage attachment to the sternum at all. Pectoral Girdle and Upper Limb The pectoral girdle connects the to the axial skeleton and consists of the left and right clavicles and left and right scapulae. The humerus is the bone of the upper arm. It forms the ball and socket with the scapula and forms the with the lower arm bones.

The radius and ulna are the two bones of the forearm. The ulna is on the medial side of the forearm and forms a hinge joint with the humerus at the elbow.

The radius allows the forearm and hand to turn over at the wrist joint. The lower arm bones form the wrist joint with the carpals, a group of eight small bones that give added flexibility to the wrist. The carpals are connected to the five metacarpals that form the and connect to each of the fingers. Each finger has three bones known as phalanges, except for the thumb, which only has two phalanges. Pelvic Girdle and Lower Limb Formed by the left and right hip bones, the pelvic girdle connects the to the axial skeleton. The is the largest bone in the body and the only bone of the thigh (femoral) region. The femur forms the ball and socket with the hip bone and forms the with the tibia and patella.

Commonly called the kneecap, the patella is special because it is one of the few bones that are not present at birth. The patella forms in early childhood to support the knee for walking and crawling. The tibia and fibula are the bones of the lower leg. The tibia is much larger than the fibula and bears almost all of the body’s weight. The fibula is mainly a muscle attachment point and is used to help maintain balance. The tibia and fibula form the ankle joint with the talus, one of the seven tarsal bones in the.

The tarsals are a group of seven small bones that form the posterior end of the foot and heel. The tarsals form joints with the five long metatarsals of the foot.

Then each of the metatarsals forms a joint with one of the set of phalanges in the toes. Each toe has three phalanges, except for the big toe, which only has two phalanges. Microscopic Structure of Bones The skeleton makes up about 30-40% of an adult’s body mass. The skeleton’s mass is made up of nonliving bone matrix and many tiny bone cells. Roughly half of the bone matrix’s mass is, while the other half is collagen protein and solid crystals of calcium carbonate and calcium phosphate.

Living bone cells are found on the edges of bones and in small cavities inside of the bone matrix. Although these cells make up very little of the total bone mass, they have several very important roles in the functions of the skeletal system. The bone cells allow bones to:. Grow and develop. Be repaired following an injury or daily wear.

Be broken down to release their stored Types of Bones All of the bones of the body can be broken down into five types: long, short, flat, irregular, and sesamoid. Long. Long bones are longer than they are wide and are the major bones of the limbs. Long bones grow more than the other classes of bone throughout childhood and so are responsible for the bulk of our height as adults. A hollow medullary cavity is found in the center of long bones and serves as a storage area for bone marrow. Examples of long bones include the femur, tibia, fibula, metatarsals, and phalanges. Short. Short bones are about as long as they are wide and are often cubed or round in shape.

The carpal bones of the wrist and the tarsal bones of the foot are examples of short bones. Flat. Flat bones vary greatly in size and shape, but have the common feature of being very thin in one direction. Because they are thin, flat bones do not have a medullary cavity like the long bones. The frontal, parietal, and of the cranium—along with the ribs and hip bones—are all examples of flat bones. Irregular bones have a shape that does not fit the pattern of the long, short, or flat bones. The vertebrae, sacrum, and coccyx of the spine—as well as the sphenoid, ethmoid, and of the skull—are all irregular bones.

The sesamoid bones are formed after birth inside of tendons that run across joints. Sesamoid bones grow to protect the tendon from stresses and strains at the joint and can help to give a mechanical advantage to muscles pulling on the tendon. The patella and the of the carpals are the only sesamoid bones that are counted as part of the 206 bones of the body. Other sesamoid bones can form in the joints of the hands and feet, but are not present in all people. Parts of Bones The long bones of the body contain many distinct regions due to the way in which they develop. At birth, each long bone is made of three individual bones separated by hyaline cartilage.

Each end bone is called an (epi = on; physis = to grow) while the middle bone is called a diaphysis (dia = passing through). The epiphyses and diaphysis grow towards one another and eventually fuse into one bone. The region of growth and eventual fusion in between the epiphysis and diaphysis is called the metaphysis (meta = after). Once the long bone parts have fused together, the only hyaline cartilage left in the bone is found as articular cartilage on the ends of the bone that form joints with other bones. The acts as a shock absorber and gliding surface between the bones to facilitate movement at the joint.

Looking at a bone in cross section, there are several distinct layered regions that make up a bone. The outside of a bone is covered in a thin layer of dense irregular connective tissue called the periosteum. The periosteum contains many strong collagen fibers that are used to firmly anchor tendons and muscles to the bone for movement. Stem cells and osteoblast cells in the periosteum are involved in the growth and repair of the outside of the bone due to stress and injury. Blood vessels present in the periosteum provide energy to the cells on the surface of the bone and penetrate into the bone itself to nourish the cells inside of the bone.

The periosteum also contains nervous tissue and many nerve endings to give bone its sensitivity to pain when injured. Deep to the periosteum is the compact bone that makes up the hard, mineralized portion of the bone. Compact bone is made of a matrix of hard mineral salts reinforced with tough collagen fibers. Many tiny cells called osteocytes live in small spaces in the matrix and help to maintain the strength and integrity of the compact bone. Deep to the compact bone layer is a region of spongy bone where the bone tissue grows in thin columns called trabeculae with spaces for red bone marrow in between.

The trabeculae grow in a specific pattern to resist outside stresses with the least amount of mass possible, keeping bones light but strong. Long bones have a spongy bone on their ends but have a hollow medullary cavity in the middle of the diaphysis.

The medullary cavity contains red bone marrow during childhood, eventually turning into yellow bone marrow after puberty. Articulations An articulation, or joint, is a point of contact between bones, between a bone and cartilage, or between a bone and a tooth. Synovial joints are the most common type of articulation and feature a small gap between the bones. This gap allows a free range of motion and space for synovial fluid to lubricate the joint. Fibrous joints exist where bones are very tightly joined and offer little to no movement between the bones.

Fibrous joints also hold in their bony sockets. Finally, cartilaginous joints are formed where bone meets cartilage or where there is a layer of cartilage between two bones. These joints provide a small amount of flexibility in the joint due to the gel-like consistency of cartilage. Skeletal System Physiology Support and Protection The skeletal system’s primary function is to form a solid framework that supports and protects the body’s organs and anchors the skeletal muscles. The bones of the axial skeleton act as a hard shell to protect the internal organs—such as the and the —from damage caused by external forces. The bones of the appendicular skeleton provide support and flexibility at the joints and anchor the muscles that move the limbs. Movement The bones of the skeletal system act as attachment points for the skeletal muscles of the body.

Almost every skeletal muscle works by pulling two or more bones either closer together or further apart. Joints act as pivot points for the movement of the bones. The regions of each bone where muscles attach to the bone grow larger and stronger to support the additional force of the muscle. In addition, the overall mass and thickness of a bone increase when it is under a lot of stress from lifting weights or supporting body weight. Hematopoiesis Red bone marrow produces red and white blood cells in a process known as hematopoiesis.

Red bone marrow is found in the hollow space inside of bones known as the. Children tend to have more red bone marrow compared to their body size than adults do, due to their body’s constant growth and development. The amount of red bone marrow drops off at the end of puberty, replaced by yellow bone marrow. Storage The skeletal system stores many different types of essential substances to facilitate growth and repair of the body. The skeletal system’s cell matrix acts as our calcium bank by storing and releasing calcium ions into the blood as needed. Proper levels of calcium ions in the blood are essential to the proper function of the nervous and muscular systems. Bone cells also release osteocalcin, a hormone that helps regulate blood sugar and fat deposition.

The yellow bone marrow inside of our hollow long bones is used to store energy in the form of lipids. Finally, red bone marrow stores some iron in the form of the molecule ferritin and uses this iron to form hemoglobin in red blood cells.

Growth and Development The skeleton begins to form early in fetal development as a flexible skeleton made of hyaline cartilage and dense irregular fibrous connective tissue. These tissues act as a soft, growing framework and placeholder for the bony skeleton that will replace them. As development progresses, blood vessels begin to grow into the soft fetal skeleton, bringing stem cells and nutrients for bone growth.

Osseous tissue slowly replaces the cartilage and fibrous tissue in a process called calcification. The calcified areas spread out from their blood vessels replacing the old tissues until they reach the border of another bony area.

At birth, the skeleton of a newborn has more than 300 bones; as a person ages, these bones grow together and fuse into larger bones, leaving adults with only 206 bones. Flat bones follow the process of intramembranous ossification where the young bones grow from a primary ossification center in fibrous membranes and leave a small region of fibrous tissue in between each other.

In the skull these soft spots are known as fontanels, and give the skull flexibility and room for the bones to grow. Bone slowly replaces the fontanels until the individual bones of the skull fuse together to form a rigid adult skull.

Long bones follow the process of endochondral ossification where the diaphysis grows inside of cartilage from a primary ossification center until it forms most of the bone. The epiphyses then grow from secondary ossification centers on the ends of the bone.

A small band of hyaline cartilage remains in between the bones as a growth plate. As we grow through childhood, the growth plates grow under the influence of growth and sex hormones, slowly separating the bones. Cost accounting carter 14th edition. At the same time the bones grow larger by growing back into the growth plates. This process continues until the end of puberty, when the growth plate stops growing and the bones fuse permanently into a single bone. The vast difference in height and limb length between birth and adulthood are mainly the result of endochondral ossification in the long bones. Diseases and Conditions A number of, from arthritis to cancer, can impair our mobility and lead to loss of quality of life or even death. At other times, symptoms of joint pain can lead to diagnoses of other underlying health problems.

Pay attention to joint pain and any changes you perceive in your ability to move, sharing those with your healthcare provider. Also, you can learn more about, which can tell you if you’re at a genetically higher risk of hemochromatosis—one of the most common hereditary disorders, causing joint pain—as well as Gaucher disease. Testing can also tell you if you’re an asymptomatic carrier of the genetic variant that you could pass along to your children. Prepared by Tim Taylor, Anatomy and Physiology Instructor.

. Study Guide to the Systems of the Body Study Guide to the Systems of the Body May 11, 2018 Study Guide to the Systems of the Body Have you ever wondered how your food is digested, or how you can breathe, or even move your arms? If you think about it, it's pretty amazing that the human body can do all of these things and more.

These actions are made possible by what are called organ systems which are collections of organs, body parts and tissues that work together for a common goal. For example, each one of your bones are part of the skeletal system; they work collectively to provide support and movement so that you can walk and run. Your bones also work together to protect your important internal organs, such as the heart, lungs and brain.

Other organ systems present in your body are the circulatory, respiratory, muscular, digestive, integumentary, endocrine, reproductive, and nervous systems. All of these systems have specific functions but they cannot function independently, meaning that they rely on all the other systems in order to work properly.

Each system is very important and every person has them. Below you will find a brief overview of each body system along with helpful educational links for adults and instructional links for teachers. Circulatory System The circulatory system consists of the heart and blood vessels which emcompasses all of the arteries, veins, and capillaries. The arteries carry oxygenated blood away from the heart, and veins return deoxygenated blood back to the heart. The main purpose of the circulatory system is to transport blood, oxygen, nutrients and hormones to and from different cells and tissues throughout the body.

This system works hand-in-hand with the respiratory system to facilitate the exchange of oxygen and carbon dioxide within the blood per the alveoli in the lungs. It is also very important for the the removal of wastes and poisons within the body via the digestive and urinary systems. Click on this link and learn all about the circulatory system. Includes information on how it works, its function, major organs within the system, heart structure, and blood. A neat animation of how the circulatory system works.

Human Skeleton Study Guide

Kids who are interested in learning more about the cardiovascular system and what it is can click on this link. On this page, readers will learn more details about the heart, the bloodstream, and how blood gets its oxygen!. This page opens up to a printout of the human heart that can be colored. The printout has the various parts of the heart labeled.

A series of lesson plans for learning about the circulatory system. Blood vessels and how to check one's pulse are a part of the lesson plans provided. Play this game to learn more about the circulatory system.

Watch a great video about the heart and the circulatory system. After the video, kids can read all about it as well. Respiratory System The respiratory system primarily consists of the trachea, bronchi, bronchioles, alveoli, lungs and diaphragm. It's primary functions are to absorb oxygen through the inhalation (inspiration) of air and to expel carbon dioxide back out into the atmosphere through exhalation (expiration). This process is commonly called ventilation, otherwise known as breathing, which facilitates the exchange of oxygen and carbon dioxide between the lungs and atmosphere.

Within the lungs, oxygen and carbon dioxide are exchanged via the alveoli, which are tiny air sacs where this action takes place. During this process the newly oxygenated blood is pumped through the circulatory system by way of the heart to all of the cells, tissues, and organs throughout the body. Educational information provided by the NIH. Includes an overview of the respiratory system, what happens when you breathe, what controls your breathing, and lung diseases and conditions. Includes 2D and 3D interactive respiratory system anatomy explorer. Provides information on each section of the respiratory system and an overview of how it all works together.

An elementary school lesson plan regarding the respiratory system. The lesson plan includes parts from part A to part D. Watch a video summary about the respiratory system. The video is for kids in the fifth grade.

Information about the respiratory system in an easy to understand format. Provides educational information on the respiratory system basics, including breathing, gas exchange, and cellular respiration. Skeletal System The skeletal system is comprised of 206 bones in total and consists of several different types of bones such as long, short, flat, irregular and sesamoid. It also consists of all the joints, cartilage, tendons and ligaments within the body.

The primary functions of the skeletal system are locomotion, support of the body, and the protection of internal organs such as the brain, heart, and lungs. Bones are also responsible for the production of red blood cells, platelets and most white blood cells. Minerals such as calcium, iron, magnesium and phosphorous are also stored within the bones, with 99% of the body’s calcium being stored here.

Learn about the skeletal system components, types of bones, and types of joints. Learn about the skeletal system inside and out by clicking on this link. While reading this page, people can also learn what the skeletal system does and how it works with other systems in the body. An interactive game for grades 4 and 5 that allows kids to label the various bones of the skeletal system. Kids can ask their parents to print out this skeleton for coloring, or it can be colored online.

Spaces are available for labeling the various parts. Learning about the common and proper names of bones can be fun. Print this PDF and connect the common names of the bones with the proper names. Read about the three major jobs that the skeletal system does. This link also tells how many bones there are in the human body. Muscular System The muscular system consists of 650 skeletal, smooth (visceral), and cardiac (myocardium) muscles. The primary functions of this system are movement, joint stabilization, heat generation, maintenance of posture, and the facilitation of blood circulation.

Skeletal muscles connect to bone and work hand-in-hand with the skeletal system to control voluntary movement such as walking and running. Smooth muscles are involuntary muscles that are responsible for the contraction of hollow muscles which include the stomach, intestines, bladder and uterus. Cardiac muscle is involuntary muscle found only in the heart and facilitates the circulation of blood by pumping it to the major arteries and out into the body via the circulatory system. Facts, Functions and Diseases: Provides an educational overview of the human muscular system.

Includes brief information about diseases of the muscular system. Easy to understand educational overview of the muscular system.

Provides more in-depth information about the muscular system. Includes a 2D and 3D interactive anatomy explorer. A collection of classroom and home-school activities and lesson plans that teach kids about their muscles. This class assignment asks two questions about the muscular system, plus includes a bonus question. Links to explore for the answer are provided. The Digestive System The digestive system is mainly comprised of the gastrointestinal (digestive) tract which includes the mouth, esophagus, stomach, small intestine, and large intestine (colon). The liver, gallbladder, and pancreas are also a part of this system and are responsible for contributing to the chemical breakdown of ingested food.

The main functions of the digestive system are digestion, absorption and the elimination of waste. Digestion is the breakdown of foods by mechanical and enzymatic processes into substances that can be utilized by the body. Absorption occurs primarily in the small intestine and is the process by which vitamins, minerals, carbohydrates, fats, and proteins are passed on to the blood for energy. Undigested and non-useful nutrients from food pass through to the large intestine and are eliminated as waste. The large intestine is also where the majority of water and sodium are absorbed into the body for use.

A more in-depth look at how the digestive system works, why it’s important, and what happens to your food as it passes through the digestive system. Click on this link for a neat video about the digestive system. Learn about the nine basic steps that the human digestive system goes through.

An online game where kids help Arnold with his digestive system. Organs are moved into the correct location on the character's body. A video that shows how the digestive system works for kids in grades 3 to 12.

Nervous System The nervous system is made up of two major parts: the central nervous system (CNS) and the peripheral nervous system (PNS). The central nervous system is made up of the brain and spinal cord and acts as the main control system for the body. The peripheral nervous system is made up of all the nerves and ganglia (nerve cell clusters) found outside of the central nervous system; its role is receiving information from various stimuli and sending it to the brain. The main purpose of the nervous system is perceiving information from inside the body and/or from the external environment (PNS) and determining how the body responds to any changes (CNS). An example of this would be pricking your finger on a needle, your body will immediately pull your finger away in direct response to painful stimuli. This system also regulates basic bodily functions such as breathing, blood pressure, digestion, and the control of body temperature. Educational overview of the nervous system from the NIH.

Make a neuron out of clay by following the instructions found on this page. The directions for the model are for kids in third grade through 12th grade. Provides easy to understand information for kids about the nervous system. Includes a slideshow on the different parts of the brain, anatomy of the nervous system, how it works, and illnesses of this system.

Learn all about the nervous system by clicking on this link to the Women's and Children's Health Network. The article even explains how to keep the central nervous system working well!. On this page, kids can learn all about the various body systems. The last system covered by this PDF document is the nervous system. Endocrine System The endocrine system is primarily made up of the hypothalamus, thyroid, parathyroid, pituitary, pineal body, adrenal glands, pancreas, and reproductive glands. The main function of this system is to help regulate and maintain assorted functions of the body by releasing hormones into the bloodstream to maintain homeostasis. Homeostasis is the condition of maintaining balance within the body in relation to its external environment and is vital for life.

Hormones are chemical substances produced by a gland, or glands, to affect other parts of the body. Together these glands are responsible for growth and development, breathing and heart rate, reproduction, metabolism, mood, sleep, tissue function, digestion, the release of insulin, and much more. Provides video addressing each endocrine gland within the body, how it works, and where the glands are located.

It also provides an overview of the endocrine system. Provides educational information for teens regarding each gland and the hormones they produce. Includes overview of the endocrine system along with common disease conditions. Printable activity sheet for labeling the endocrine glands. Includes educational information on the endocrine glands, the hormones they secrete and where they are located.

Activity plan for teachers. This game teaches students about the hormone-receptor interactions within the endocrine system. Integumentary System The integumentary system consists of the skin, sweat and oil glands, nails, and hair. Skin is the largest organ in the body and is made up of three layers: the epidermis, dermis, and subcutaneous tissue.

This system performs several functions that are vital to maintaining homeostasis. These functions are: protecting the body’s internal organs and tissues; protection from dehydration by helping to retain body fluids; protection from infectious organisms; maintaining a body temperature that is consistent with life; receptor site for pressure, sensation, pain, and temperature; excretion of waste materials through sweating; storing fat, water, and glucose; production of vitamin D. Hair is responsible for helping to protect the skin from ultraviolet radiation, while nails help to protect from injury and provide support for the tips of the fingers and toes. Provides general information about this system including the structure of the skin and the different layers. An educational video about the integumentary functions and anatomy is also included.

Educational information about each layer of the skin in an easy to understand format. Lesson plan for teachers that encourages learning about the four functions of the skin. Infographic diagram on the human integumentary system. Also contains basic information about this system.

Urinary/Excretory System The urinary system is made up of the kidneys, ureters, bladder and urethra. The kidneys filter and remove extra fluid, toxins and waste from the bloodstream in the form of urine. Every day this system produces at least 1 to 2 quarts of urine. Other primary functions of the urinary system are maintaining the body’s relative state of homeostasis by keeping the levels of electrolytes in balance, producing hormones that regulate blood pressure, producing red blood cells, and helping to keep bones healthy by maintaining the right amounts of phosphorous and calcium within the body. Educational information from the NIH about this system and its functions. Provides anatomical information about each organ within the system.

Provides information about this system to kids in an easy to understand format. Educational and funny video for children about the urinary system and how it works. Teacher’s lesson plan and activity on the excretory system geared toward elementary school students. Lymphatic System The lymphatic system consists of the lymphatic vessels, tonsils, adenoids, spleen and thymus gland. Lymphatic vessels are similar to the circulatory system’s capillaries and veins and are connected to hundreds of lymph nodes within the body. Lymph nodes produce and store the cells that fight infection and disease. Tonsils take in bacteria and viruses that enter through the mouth and nose and are considered the first line of defense for the immune system.

The spleen is the largest lymphatic organ and is responsible for producing both red and white blood cells and helps to detect dangerous microorganisms, viruses and bacteria within the blood. As part of the immune system, the primary function of the lymphatic system is to transport a clear and colorless infection-fighting fluid called lymph, which contains white blood cells, throughout the body via the lymphatic vessels. Other functions of this system are absorbing fats and fat-soluble vitamins from the digestive system and transporting them into the bloodstream, restoring excess proteins and interstitial fluids to the blood, and helping to rid the body of toxic byproducts. Information from the CDC about each organ in the lymphatic system, where it is found and what they produce. Spleen and Lymphatic System: Provides information about the basic anatomy of the lymphatic system, how it works and disease conditions associated with this system. Crash Course: Educational and funny video about the lymphatic system. Provides a transcript of the video for the hearing impaired.

Fun interactive and educational online game for children. Reproductive System The reproductive system in men consists of the penis, scrotum and testicles and in women it consists of the ovaries, fallopian tubes, uterus, vagina, breasts and mammary glands. Together there are four main functions of the reproductive system: the production of hormones such as testosterone, progesterone and estrogen; the production of egg and sperm cells; the sustenance and transportation of these cells; and the development and nurturing of offspring. This system is vital to the survival of the human species through creating new life. Overview of descriptions and functions of the male and female reproductive organs. Provides educational information for teen boys about the male reproductive system in an easy to understand format.

Provides educational information for teen girls about the female reproductive system. Provides several SexEd lesson plans for teachers geared for students from 4th grade through high school.

See also for specific information on the heart.