Regents Biology 2007-2008

Skeletons & Muscles

Regents Biology

Animal Movement

What are the advantages of being mobile?1. Find food 2. escape 3. migrate 4. find a mate

mobileable to move from

place to place

sessilestay in one place

Ex: barnacles

Regents Biology

Human endoskeleton

206 bones

Axial skeletonskull, rib cage,

spine

Appendicular Skeleton

hips, shoulders, arms and legs

Regents Biology

Human endoskeleton

Functions

1. support

2. protect

3. Move4. Store minerals5. Make blood cells

Ossification – the replacement of cartilage by bone

Regents Biology

6 Types of Joints – Name, type of movement, example

1. Ball and socket• Wide range of movement - ex. Hips and shoulders

2. Hinge• Back and forth movement – ex. Wrist and knee

3. Pivot • Twisting movement – ex. Neck and elbow

4. Fixed• NO movement – ex. skull

5. Gliding• Sliding movement – ex. Wrist and ankle

6. Saddle• Allows thumb to cross over palm – ex. Thumb ONLY

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3 Types of Muscle

voluntaryinvoluntary,contract on their own

involuntary

Connect to boneWork in pairsStriated or striped

NOT striatedControlled by the medullaExample – peristalsis, diaphragm

Heart ONLYStriated

striated

smooth

cardiac

Regents Biology

Muscle movement Muscles do work by contracting (shortening)

Muscles can only pull bone skeletal muscles come in antagonistic pairs

Muscles work against each other Flexor (bends) vs. extensor (straightens)

Regents Biology

3 Types of connective tissue♦Tendons - connect bone to muscle

Ligaments - connect bone to bone

Cartilage – cushions between bones

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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

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Muscle limits Muscle fatigue

lack of ATP – anaerobic respiration low O2

lactic acid lowers pH which interferes with enzyme (protein) function

Muscle cramps build up of lactic acid – causes the

“burn” lack of (ATP) massage or stretching increases

circulation

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Diseases – failure to maintain homeostasis

ALS - amyotrophic lateral sclerosis(Lou Gehrig’s disease)motor neurons degenerate

Osteoporosis – loss of Calcium Arthritis – loss of cartilage – bones

“rub” together Tendonitis Leukemia – cancer of bone marrow