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Text Comments (3)

1 answer

Last reply by: Dr Carleen Eaton
Thu Nov 17, 2011 4:52 PM

Post by Daniel Delaney on November 17, 2011

Dr. Eaton, It is amazing in how clearly you explain everything; you are a tremendous help.

0 answers

Post by bo young lee on December 18, 2012

i dont understand the summation and tetanus

Musculoskeletal System

  • The skeletal system functions in support, protection and mobility. An exoskeleton is located outside of the body, while an endoskeleton is located on the inside of the body.
  • Bone is a type of connective tissue. It is mineralized, which accounts for its strength. Cartilage is also connective tissue but is more flexible than bone.
  • Skeletal muscle cells are large and multinucleated. Skeletal muscle is striated due to the regular arrangement of actin and myosin within muscle fibers.
  • The contractile unit of skeletal muscle is the sarcomere.
  • According to the sliding filament theory, during muscle contraction the thick and thin filaments slide past one another, causing the sarcomere to shorten.
  • Smooth muscle is under involuntary control. It lacks striations and unlike skeletal muscle, the cells have only one nucleus each.
  • The heart is composed of cardiac muscle. Cardiac muscle is striated and is inherently contractile

Musculoskeletal System

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

AP Biology Intro