MUSCULAR SYSTEM

1
MUSCULAR SYSTEM

• pp. 917-920

2
FUNCTION

• Support, movement, and protection

3
TYPES

• skeletal muscles that move bones (voluntary)
• smooth involuntary muscles that protect organs
• cardiac involuntary muscles found only in heart

4
MUSCLE STRUCTURE (external)

• Tendons connect muscle to bone
• When the muscle moves, the bones move, and the
  joint bends

5
(No Transcript)
6
MUSCULAR MOVEMENT

• Muscles arranged in opposing pairs and while one
  relaxes the other contracts
• flexor contraction bends the joint
• extensor contraction straightens the
  
• joint

7
MUSCLE STRUCTURE (internal)
myofibril ?muscle cell (fiber)?fascicle ?muscle
8

• Two types of proteins (actin and myosin) involved
• actin myosin ? myofibril
• myofibril attaches to Z line
• sarcomere functional unit from Z line to Z line

9
MUSCLE CONTRACTION
10

• contraction shortening of sarcomere between Z
  lines
• myosin heads walk along the actin
• this requires ATP to walk and to release the
  myosin after walking

11
(No Transcript)
12
ENERGY and FATIGUE

• Aerobic respiration breaking down organic
  compounds to release energy to be used by the
  body
• Fatigue is the inability to contract (and
  release) the muscle due to the lack of ATP

13
SKELETAL SYSTEM

• pp 911-916

14
FUNCTION

• Bones supports and protects organs
• Gives shape and structure to the body
• Produce red and white blood cells

15
SKELETON

• Axial the skull, face, vertebral column, and rib
  cage.
• Appendicular the arms and legs, pelvis, scapula,
  collar bone, etc
• Includes bones and their associated tissues
  (cartilage and ligaments)

16
BONE STRUCTURE

• Porous and made of proteins and minerals and
  contains
• a) Osteocytes cells that make bone
• b) Bone marrow soft bone tissue that produces
  platelets and blood cells

17
BONE DEVELOPMENT

• Bones develop from cartilage hardening
  (ossification)

18
JOINTS

• Place where two bones meet

19

• Fixed no movement between bones (ex. skull).
• Semimovable limited movement (i.e. rib cage and
  vertebrae)
• Movable see your coloring

20
JOINT STRUCTURE

• Cartilage between joints for cushion
• Ligaments connect joints