Regents Biology Skeletons & Muscles

Regents Biology Animal Movement What are the advantages of being mobile? 1. Find food 2. escape 3. migrate 4. find a mate mobile able to move from place to place sessile stay in one place Ex: barnacles

Regents Biology Human endoskeleton 206 bones Axial skeleton skull, rib cage, spine Appendicular Skeleton hips, shoulders, arms and legs

Regents Biology Human endoskeleton Functions 1. support 2. protect 3. Move 4. Store minerals 5. 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

Regents Biology 3 Types of Muscle voluntary involuntary, contract on their own involuntary Connect to bone Work in pairs Striated or striped NOT striated Controlled by the medulla Example – peristalsis, diaphragm Heart ONLY Striated 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

Regents Biology 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

Regents Biology Muscle limits  Muscle fatigue  lack of ATP – anaerobic respiration  low O 2  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

Regents Biology 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