Bones, Muscles, and Skin. * 4&feature=related 4&feature=related.
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Transcript of Bones, Muscles, and Skin. * 4&feature=related 4&feature=related.
Bones, Muscles, and Skin
*The Human Body
*Organization of the Human Body
*http://www.youtube.com/watch?v=chqwSh4ii84&feature=related
*Organization of the Human Body
*Cells – the basic unit of structure and function
*100 trillion in the adult human body
*Play specific roles
*Tissues – a group of connected cells that have a similar function
*Connective tissue – Form the bodies structure
*Bone and Cartilage
*Organization of the Human Body
*Types of Tissues
*Epithelial tissue
*Line the inner and outer body surfaces
* Skin, lining of the digestive tract
*Protects the body and its internal organs
* Secretes substances like hormones
* Absorbs substances like nutrients
*Organization of the Human Body
*Tissues
*Muscle Tissue
*Have a unique ability to contract
*Attached to bone allowing the body to move
*Nervous Tissue
*Made up of neurons that carry electrical impulses
* Brain and nerves that connect the brain to all other parts of the body
*Organs and Organ Systems
*An organ is a structure that consists of two or more types of tissues that work together to do the same job
*Brain, lungs, heart, skin, kidneys
*In Humans organs are organized into organ systems
*Work together to carry out a complex overall function
* Each organ does a part of a much larger job
* http://www.youtube.com/watch?v=po8D290YF9o&feature=related
*The End Result
*A well-oiled machine
*Closely controlled and regulated by the nervous and endocrine systems
*Nervous system does the controlling of the body systems
*The endocrine system secretes hormones that regulate the activities
*Functioning together they maintain homeostasis
* Temperature, pH, and other conditions at just the right levels to support life
*Maintaining Homeostasis
*Respiratory System
*A high concentration of carbon dioxide in the blood triggers faster breathing.
*The lungs exhale more frequently which removes carbon dioxide from the body more quickly
*Excretory System
*Low level of water in the blood triggers retention of water by the kidneys
*Kidney’s produce more concentrated urine, so less water is lost from the body
*Maintaining Homeostasis
*Endocrine System
*High concentration of sugar in the blood triggers secretion of insulin by the pancreas
* Insulin helps cells absorb more sugar from the blood stream
*Homeostasis Failure
*Cells may not get everything they need
*Toxic wastes may accumulate in the body
*Imbalance may lead to disease or even death
*The Skeletal System
*All the bones of the body
*In adults there are 206 bones
*Cartilage provides a smooth surface on which the joints can move
*Ligaments hold bones together
*The Skeletal System
*Functions
*Protection of internal organs
*Providing attachment surfaces for muscles
*Producing blood cells
*Storing minerals
*Maintaining mineral homeostasis
*Need just the right amount of calcium in the blood for normal body functioning
*Bones can absorb excesses
*Structure of Bones
*Very different from what we might think from looking at the bones of a skeleton
*Bones are very much alive
*Structure of Bones
*Bone matrix
*Compact and spongy bone
*Tough protein fibers (collagen) that becomes hard and rigid due to mineralization with calcium crystals
*Crisscrossed with blood vessels and nerves
*Contains bones cells involved in metabolism
*http://www.youtube.com/watch?v=4qTiw8lyYbs
*Bone Cells
*Osteoblasts – make new bone cells and secrete collagen that mineralizes to become bone matrix
*Bone growth
*Uptake of minerals from the blood
*Osteocytes – regulate mineral homeostasis
*Direct uptake of minerals from the blood and the release of minerals back into the blood as needed
*Bone Cells
*Osteoclasts – dissolve mineral in bone matric and release them back into the blood
*http://www.youtube.com/watch?v=yENNqRJ2mu0&feature=related
*Bone Tissues
*Compact Bone
*Makes up the dense outer layer of bone
*Hard and strong
*Spongy bone
*Found inside bones and is lighter and less dense than compact bone because it is porous
*Bone marrow
*A soft connective tissue that produces blood cells
*Found inside the pores of spongy bone
*Bone Tissues
*Periosteum
*A tough, fibrous membrane that covers and protects the outer surfaces of bones
*Growth and Development of
Bones
*Fetus – cartilage only
*Will turn into hard bone by a process called ossification
*Mineral deposits replace the cartilage
*By birth several area of cartilage remain
* End of long bones
* Remains as the bones grow
*Skeletal maturity reach by about age 20 and growth will stop
*Will increase in thickness
*Bone Growth
*Joints
*A joint is where two or more bones meet
*Immovable – allow no movement
*Skull
*Partly moveable – allow very limited movement
*Held together by cartilage
*Ribs and sternum
*Moveable – allow the most movement
*Connected by ligaments
*Most common type of joint
http://www.youtube.com/watch?v=SOMFX_83sqk
*Joints
*Moveable
*Also called synovial joints
*Space between is filled with a thick fluid called synovial fluid that cushions the joint
*Ball and Socket – shoulder
*Hinge – knee
*http://www.youtube.com/watch?v=zWo9-3GJpr8&feature=related
*Skeletal System Problems
*Fractures – breaks in bone – heal when osteoclasts form new bone
*http://www.youtube.com/watch?v=qVougiCEgH8&feature=PlayList&
*Osteoarthritis – cartilage breaks down causing joint stiffness and pain
*http://www.youtube.com/watch?v=F8YLJxiNh9Y
*Rickets
*http://www.youtube.com/watch?v=2ULfxsJKBuw
*The Muscular System
*Introduction
*Includes all of the muscles of the body
*Made up of muscle cells which are also called muscle fibers
*These muscles fibers can contract or shorten
*No other cell in the body can do this
*This is responsible for all movement of the body both inside and out
*Types of Muscle
*Types of Muscle
*Smooth Muscle
*Walls of internal organs like the stomach and intestines
*Helps the organs carry out their functions
*These contractions are involuntary
*They are not under conscious control
*Types of Muscle
*Skeletal Muscle
*This type of muscle is attached to bone
*Contractions of skeletal muscles are voluntary
*They are under conscious control
*The most common type of muscle
*More on this in a moment
*Types of Muscle
*Cardiac Muscle
*Found in in the walls of the heart
*When it contracts the heart beats and pumps
*Contains lots of mitochondria which produces ATP for energy
*Helps the heart resist fatigue
*Contractions are involuntary
*Skeletal Muscles
*Over 600 in the human body
*Vary greatly in size
*Contain hundreds to thousands of muscle fibers
*Surrounded by connective tissue
*Skeletal Muscleshttp://www.youtube.com/watch?v=XoP1diaXVCIhttp://www.youtube.com/watch?v=uY2ZOsCnXIA&lr=1
*Skeletal Muscles and Bones
*Bones and muscles are connected by tendons
*Muscles can only contract
*So to move in opposite directions they must work together to make that happen
http://www.youtube.com/watch?v=T-ozRNVhGVg&feature=related
*Use it or lose it
*Using skeletal muscles such as in weight lifting causes the muscle to increase in size and strength
*Running increases the strength and efficiency of cardiac muscle
*Continual exercise is necessary to maintain bigger, stronger muscles
*If you don’t use muscle, it get smaller and weaker
*Muscle Contraction
*Happens when muscle fibers shortens
*Muscle Fibers
*Contain organelles called myofibrils
*Made up of two types of protein filaments
* Actin (Thinner) and Myocin (Thicker)
* Actin are connected to structure called Z lines
* Region between two Z lines is called a sacromere
* Actin and Myocin filaments overlap within the sacromere
* Myocin has tine structures called cross bridges that can attach to actin fiber
*Sliding Filament Theory
*http://www.youtube.com/watch?v=7V-zFVnFkWg&feature=related
*Muscles and Nerves
*Muscles need a stimulus to contract
*This message comes in the form of an electrical nerve impulse from the brain to nerve cells called motor neurons
*This neurons cause to muscle to perform the action the is desired
* (Involuntary contractions of cardiac and smooth muscles are also controlled by nerves)
*The Integumentary
System
*Skin
*Integumentary system
*Skin, hair, nails
*Provide protective covering
*Help maintain homeostasis
*http://www.youtube.com/watch?v=IAAt_MfIJ-Y
*Skin
*The largest organ in the body
*1 Square inch of skin
*20 blood vessels
*650 sweat glands
*1000+ nerve endings
*60,000 pigment producing cells
*On 2 mm thick
*http://www.youtube.com/watch?v=uH_uzjY2bEE&feature=fvw
*Epidermis and Dermis
*http://www.youtube.com/watch?v=d-IJhAWrsm0&feature=related
*Epidermis
*The outer layer of skin
*Make up of epithelial cells and little else
*No nerve endings or blood vessels
*Innermost cells are continually undergoing mitosis to form new cells
*They move up through the layers as needed
*Produce a tough, fibrous protein called keratin
* Fill and then die by the time they reach the surface
* Form a protective waterproof layer called the stratum corneum
*Epidermis
*Contains melanocytes
*Produce melanin – brownish pigment that gives skin its color
*Amount produced is determined by heredity
* Increases due to exposure to UV radiation
* Tanning
* Also stimulates the skin to produce vitamin D
* Melanin prevents UV radiation from penetrating the skin
* Darker skinned people may be subject to a Vitamin D deficiency
*Dermis
*Lower layer of skin directly below the epidermis
*Made of tough connective tissue and attached to the epidermis by collagen fibers
*Blood vessels and nerve ending
*Hair follicles and two types of glands
*Dermis
*Hair follicles are when hairs originate – grow out of follicles and exit at the surface of the skin
*Sebaceous glands – produce an oily substance called sebum
*Secreted into hair follicles and makes its way to the surface
*Waterproofs the hair and skin and helps prevent them from drying out
*Antibacterial as well
*Dermis
*Sweat glands
*Produce the salty fluid called sweat
*Contains excess water, salts, and other waste products
*Ducts that pass through the epidermis and open to the surface of the skin through pores
*Functions of the Skin
*Preventing water loss
*Barrier to the entry of microorganisms
*Melanin blocks UV light and protects the deeper layers of the skin from its dangerous effects
*Regulate body temperature
*Skin Problems
*Acne
*Pimples form on the skin due to bacterial infection
*Affects 85% of teens and may continue into adulthood
*Due to excessive secretion of sebum
* Plugs hair follicles and makes them good breeding grounds for bacteria
* http://www.youtube.com/watch?v=11I7ONVqcc0
*Skin Problems
*Skin cancer
*Skin cells grow out of control
*Caused mainly by excessive exposure to UV radiation
*People with fair complexions are at greater risk
*Wear sunscreen and protective clothing
*Nails and Hair
*Nails – fingernails and toenails
*Specialized epidermal cells that are filled with keratin
*Tough and hard
*Fingernails also enhance sensations by acting as a counterforce to the sensitive fingertips when objects are handled
*Nails and Hair
*Hair
*Found only in mammals
*Main component is keratin
* Shaft is dead, keratin-filled cells that overlap each other like shingles on a roof
*Helps shed water
* Insulate and protect the body
*Prevents heat loss
*Eyelashes and eyebrows protect the eyes
*Hairs in the nose traps dust and microorganisms along with sensory input