Download - Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

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Page 1: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Chapter 38: Protection, Support, Movement: Skin, Skeleton, and

Muscle

Page 2: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 40-11

Epidermis

Dermis

Hypodermis

Adipose tissue

Blood vessels

Hair

Sweatpore

Muscle

Nerve

Sweatgland

Oil glandHair follicle

Page 3: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 50-25a

Bundle ofmuscle fibers

Muscle

Single muscle fiber(cell)

Nuclei

Z lines

Plasma membrane

Myofibril

Sarcomere

Page 4: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 50-25b

TEM

Thickfilaments(myosin)

M line

Z line Z line

Thinfilaments(actin)

Sarcomere

0.5 µm

Page 5: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 50-26

Z

Relaxedmuscle

M Z

Fully contractedmuscle

Contractingmuscle

Sarcomere0.5 µm

ContractedSarcomere

Page 6: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 50-30Spinal cord

Motor neuroncell body

Motor neuronaxon

Nerve

Muscle

Muscle fibers

Synaptic terminals

Tendon

Motorunit 1

Motorunit 2

Page 7: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 50-29

Sarcomere

Ca2+

ATPasepump

Ca2+ released from SR

Synapticterminal

T tubule

Motorneuron axon

Plasma membraneof muscle fiber

Sarcoplasmicreticulum (SR)

Myofibril

Synaptic terminalof motor neuron

Mitochondrion

Synaptic cleft T Tubule Plasma membrane

Ca2+

Ca2+

CYTOSOL

SR

ATP

ADPP i

ACh

Page 8: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 50-27-4

Thinfilaments

ATP Myosin head (low-energy configuration

Thick filament

Thin filament

Thickfilament

Actin

Myosin head (high-energy configuration

Myosin binding sites

ADPP i

Cross-bridgeADP

P i

Myosin head (low-energy configuration

Thin filament movestoward center of sarcomere.

ATP

ADP P i+

Page 9: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 50-28

Myosin-binding site

Tropomyosin

(a) Myosin-binding sites blocked

(b) Myosin-binding sites exposed

Ca2+

Ca2+-binding sites

Troponin complexActin

Page 10: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 50-31

Summation oftwo twitches

Tetanus

Singletwitch

Time

Tens

ion

Pair ofaction

potentials

Actionpotential Series of action

potentials athigh frequency

Page 11: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 40-5k

Skeletal muscle

Multiplenuclei

Muscle fiber

Sarcomere

100 µm

Page 12: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 40-5l

Smooth muscle

Nucleus

Musclefibers

25 µm

Page 13: Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 40-5m

Nucleus Intercalateddisk

Cardiac muscle

50 µm