Transcript Lesson 2 - The Skeletal and Muscular Systems - Hitchcock

Unit 1 Lesson 2 The Skeletal and Muscular Systems
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What’s Inside?
What are the main functions of the
skeletal system?
• A skeleton is a system of bones which are alive.
• The skeletal system is the organ system that
supports and protects the body and allows it to
move.
• An endoskeleton is a skeleton inside the body.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are the main functions of the
skeletal system?
• The skeletal system stores minerals and produces
red blood cells.
• Bones, like the ribcage and skull, provide
protection for organs like the heart and brain.
• Bones provide support for your body and make it
possible to stand and sit.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are the main functions of the
skeletal system?
• Bones provide a place for muscles to attach. The
muscles pull on bone and cause movement.
• Marrow is a soft tissue at the center of bones. Red
marrow makes red and white blood cells.
• The hard outer layer of bone, called compact
bone, stores minerals such as calcium.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
No Bones About It!
What are the parts of the skeletal
system?
• The skeletal system is divided into two parts.
• The skull, vertebrae, and ribs make up the axial
skeleton, which supports and protects the internal
organs.
• The appendicular skeleton includes the arms, legs,
shoulders, and pelvis.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are the parts of the skeletal
system?
• Bones are alive. They have a blood supply and
nerves.
• A ligament is the tough, flexible strand of
connective tissue that holds bones together.
• Cartilage is a strong, flexible, and smooth
connective tissue found at the end of bones that
allows them to move smoothly.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are bones made of?
• Compact bone is dense and hard, with no visible
open spaces.
• Spongy bone provides most of the strength and
support for the bone. It has many open spaces.
• Bones also contain marrow, the soft tissue in the
center of bones.
• Calcium, the most plentiful mineral in bones, is
deposited by bone cells called osteoblasts.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are bones made of?
• Connective tissue is made mostly of a protein
called collagen, which allows bones to be a bit
flexible.
• Red marrow, at the center of flat bones, makes
red and white blood cells.
• Yellow marrow, at the center of long bones, stores
fat.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are bones made of?
• What are the functions of each of the parts of
bone?
v
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
How do bones grow?
• Babies have cartilage that is later replaced by
bone.
• Growth plates are locations where long bones
lengthen.
• Osteocytes are bone cells that move into cartilage
and harden it into bone.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
Bone Connections
How are bones connected?
• A joint is the place where two or more bones
connect.
• Fixed joints are found in the skull and allow no
movement between bones.
• Movable joints allow movement of the bones.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
How are bones connected?
• Ball and socket joints allow one of the bones to
rotate in a large circle.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
How are bones connected?
• Gliding joints allow flexibility in the wrist and
ankles.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
How are bones connected?
• Hinge joints allow bones to move back and forth.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are some injuries and disorders
of the skeletal system?
• Fractures are bones that are broken.
• Sprains are injuries to a ligament caused by
stretching a joint too far.
• Osteoporosis is a disease that causes bone to
become thin and weak.
• Arthritis is a disease that causes joints to stiffen,
swell, and become painful. Sometimes the joint
becomes misshapened.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
Keep Moving!
What are the main functions of the
muscular system?
• The muscular system is mostly made of the
muscles that allow a body to move and be flexible.
• Muscle is the tissue that contracts and relaxes,
making movement possible.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are the three types of muscles?
• The three types of muscle are skeletal, smooth,
and cardiac.
• Voluntary muscle is skeletal muscle that you are
able to control.
• Involuntary muscle is the smooth and cardiac
muscle you cannot control.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are the three types of muscles?
• Smooth muscle is found in internal organs and
blood vessels.
• Cardiac muscle is the tissue that makes up the
heart.
• Skeletal muscle is attached to bones by tough
strands of tissue called tendons.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are the three types of muscles?
• Most skeletal muscles work in pairs around a joint.
• The flexor bends the joint.
• The extensor straightens the joint.
• As one muscle contracts, the other muscle relaxes.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are the three types of muscles?
• Point out the location of a flexor muscle and an
extensor muscle.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
Move It or Lose It!
What are some injuries and disorders
of the muscular system?
• A strain is a muscle injury in which a muscle is
overstretched or torn.
• Muscular dystrophy causes skeletal muscle to
become weaker over time.
• Tendinitis occurs when tendons become inflamed
or torn.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are some benefits of exercise?
• Exercise is any activity that helps improve
physical fitness and health.
• Exercise can increase strength, endurance, and
flexibility. It can also improve heart and lung
function and reduce stress.
• People should get 30 to 60 minutes of exercise a
day.
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Unit 1 Lesson 2 The Skeletal and Muscular Systems
What are some benefits of exercise?
• Resistance exercises are anaerobic exercises.
Anaerobic exercises do not require oxygen for
contraction, and involve short bursts of intense
effort.
• Endurance exercises are aerobic exercises.
Aerobic exercises require oxygen for contraction,
and involve extended periods of movement.
• Flexibility is improved by stretching muscles.
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