musculoskeletal system
DESCRIPTION
Muscular and Skeletal system combinedTRANSCRIPT
Musculoskeletal System
Introduction
The Musculoskeletal system is made up of two different systems.
It is important to know how each system works.
Three Types of Muscles
The three types of muscles tissues are:– Smooth– Skeletal – Cardiac
Smooth Muscle
smooth (or visceral) muscle- – forms the muscle layers in the walls of the
digestive tract, bladder, various ducts, arteries and veins, and other internal organs.
– Smooth- muscle cells are elongated and thin, have only one nucleus, and form sheets rather than bundles of muscles.
– Smooth muscle is controlled by the autonomic nervous system (ANS).
Smooth Muscle
Skeletal Muscle
skeletal (or voluntary/striated) muscle, is the most abundant tissue in the human body, it produces movement.
Each skeletal-muscle fiber is roughly cylindrical, contains many nuclei, and is crossed by alternating light and dark bands called striations.
Fibers bind together, via connective tissue, into bundles; and these bundles, in turn, bind together to form muscles.
Thus, skeletal muscles are composite structures composed of many muscle fibers, nerves, blood vessels, and connective tissue.
Skeletal muscles are controlled by the somatic nervous system (SNS).
Skeletal Muscle
Cardiac Muscle
cardiac (or heart) muscle, a cross between the smooth and striated muscles, makes up the heart tissue.
Like smooth muscle, it is controlled by the autonomic nervous system (ANS).
Cardiac Muscle
Muscle Function
There are two important proteins involved in muscle function.
– Actin – Myosin
They overlap at an area called the sarcomere.
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Muscle Function
Skeletal System
Its 206 bones form a rigid framework to which the softer tissues and organs of the body are attached.
Vital organs are protected by the skeletal system.
They also function to move, support, produce red and white blood cells and store minerals.
The parts of the skeleton
The human skeleton is divided into two distinct parts:
– Axial– Appendicular
Axial Skeleton
The axial skeleton consists of bones that form the axis of the body and support and protect the organs of the head, neck, and trunk.The Skull
The Sternum
The Ribs
The Vertebral Column
Appendicular Skeleton
The appendicular skeleton is composed of bones that anchor the appendages to the axial skeleton.– The Upper Extremities– The Lower Extremities– The Shoulder Girdle– The Pelvic Girdle--(the sacrum and coccyx are
considered part of the vertebral column)
Sacrum
Composition of bones
Bone is not a uniformly solid material, but rather has some spaces between its hard elements.
Two types of bone tissue
– Compact– Spongy
Compact Bone
The hard outer layer of bones is composed of compact bone tissue, so-called due to its minimal gaps and spaces.
This tissue gives bones their smooth, white, and solid appearance, and accounts for 80% of the total bone mass of an adult skeleton.
Spongy Bone
Filling the interior of the organ is the trabecular bone tissue (an open cell porous network also called cancellous or spongy bone) which is composed of a network of rod- and plate-like elements that make the overall organ lighter and allowing room for blood vessels and marrow.
Trabecular bone accounts for the remaining 20% of total bone mass, but has nearly ten times the surface area of compact bone.
Bone Cells
Osteoblasts: are mononucleate bone-forming cells. Osteoblasts also manufacture hormones, to act on the bone itself.
Osteocytes originate from osteoblasts. Their functions include formation of bone, matrix maintenance and calcium homeostasis.
Osteoclasts are the cells responsible for bone resorption (remodeling of bone to reduce its volume).
Five different types of bones
Long (femur) Short (carpus) Flat (sternum) Irregular (vertebrae) Sesamoid (embedded
in tendon)
Disorders
Bone fracture Osteomyelitis Osteoporosis Osteosarcoma Osteogenesis
imperfecta Arthritis
How do they work together?
The musculoskeletal system consists of the skeletal system -- bones and joints and the skeletal muscle system. These two systems work together to provide basic functions that are essential to life, including:
Protection Support Blood cell formation Mineral homeostasis Storage: stores fat and minerals. Leverage
Tissues involved
There are 5 basic tissues comprising the musculoskeletal system: – bones, – ligaments (attaching bone to bone) – cartilage (protective gel-like substance lining the
joints and intervertebral discs), – skeletal muscles– tendons (attaching muscle to bone).
How do our muscles and bones work together to cause locomotion?
Joint: where two bones meet
2 types: – Structural– Functional
Structural Joints
Fibrous Cartilaginous Synovial
If you have a weak stomach look away now!!
Functional Joints
Functional joints are classified by the range of movement they provide
– synarthroses – amphiarthroses – diarthrosis
Moveable joints
Ball and socket Hinge Pivot Gliding Saddle Condyloid
Categories of moveable joints
How do muscles work to move joints?
Flexor Vs Abductor– Flexor contracts– Abductor extends
Homeostasis and muscles
Feedback loop– Cold weather– Reflex
Muscles help you respond to changes in your environment by enabling you to move.