1. Skeletons & Muscles

2. Animal Movement What are the advantages of being mobile? sessile

3. Lots of ways to get around…

4. Lots of ways to get around…
mollusk
mammal
bird
reptile

5. Lots of ways to get around…
bird
insect
mammal
bird

6. Human endoskeleton 206 bones Axial Division Appendicular
Skull, vetebral column & rib cage
Appendicular
Arm and leg bones, pelvis and shoulder bones
ball & socket
hinge
206 bones
pivot

7. What are bones made-up of?
Living Parts (1/3)
Cartilage cells
Osteocytes (bone cells)
Connective tissue
Tendons- muscle to bone
Ligaments – bone to bone
Blood Vessels and nerves (found in Haversian canals)
Nonliving Parts (2/3)
Mineral Deposits
Calcium carbonate
Calcium phospate
Ossification: the process in which temporary cartilage is replaced by osteocytes

8. Structure of Bones Spongy bone Middle and end of bones
Gives strength with out adding mass
Compact bone
Outer part of bone
Haversian canals run through it
Contains blood vessels & nerves
Bone Marrow
Yellow marrow – made up of fat
Red marrow – makes red blood cells and some white blood cells
Cartilage
Found at ends of mature bones
Protects the joints

9. Muscle evolved first involuntary, found only in heart
contract on their own
Slight striations and single nucleus
Attached to bone, Voluntary
Have stripes (striations) and many nuclei
All cells have a fine network of actin and myosin fibers that contribute to cellular movement. But only muscle cells have them in such great abundance and far more organized for contraction.
SMOOTH MUSCLE Smooth muscle was the first to evolve. Lining of blood vessels, wall of the gut, iris of the eye. Some contract only when stimulated by nerve impulse. Others generate electrical impulses spontaneously and then are regulated by nervous system.
CARDIAC MUSCLE Small interconnected cell with only one nucleus. Interconnected through gap junctions. Single functioning unit that contract in unison via this intercellular communication. Mostly generate electrical impulses spontaneously. Regulated rather than initial stimulation by nervous system.
SKELETAL MUSCLE Fusion of many cells so multi-nucleated. Attached by tendon to bone. Long thin cells called muscle fibers.
Involuntary, found in organs
No striations and single nucleus
evolved first

10. Organization of Skeletal muscle
tendon
muscle fiber (cell)
bundles of protein fibers
protein fibers

11. Muscles movement Muscles do work by contracting
skeletal muscles come in antagonistic pairs
flexor vs. extensor
contracting = shortening
move skeletal parts
tendons
connect bone to muscle
ligaments
connect bone to bone

13. The Trigger: motor nerves
Motor nerves trigger muscle contraction

14. Fast twitch & slow twitch muscles
Slow twitch muscle fibers
contract slowly, but keep going for a long time
more mitochondria for aerobic respiration
long distance runner
“dark” meat = more blood vessels
Fast twitch muscle fibers
contract quickly, but get tired rapidly
sprinter
“white” meat

15. Muscle limits Muscle fatigue Muscle cramps lack of sugar low O2
lack of ATP
low O2
lactic acid lowers pH which interferes with protein function
nerve fatigue
loss of chemical transmitter
Muscle cramps
build up of lactic acid
lack of energy (ATP)
ion imbalance
massage or stretching increases circulation

16. Diseases of Muscle tissue
ALS
amyotrophic lateral sclerosis
Lou Gehrig’s disease
motor neurons degenerate
Myasthenia gravis
auto-immune
antibodies to nerve transmitter chemical
Stephen Hawking

17. Botox Bacteria Clostridium botulinum toxin
blocks release of nerve transmitter
but botulism can be fatal!
muscle