PROTECTION,

SUPPORT,

MOVEMENT

PROTECTION, SUPPORT & MOVEMENT

Integumentary

system

Skeletal system

Muscular system

2

INTEGUMENT

“Skin”

Function

Physical barrier to environment

Protection from dehydration

Temperature regulation

Vitamin D production

3

Human Skin

3 Layers

Epidermis

Outermost layer of

dead, flattened cells

Pigmented cells

Non-vascular

4

Human Skin

3 Layers

Epidermis

Dermis

Blood capillaries

Hair follicles

Sweat & oil glands

Mechanoreceptors

Dense irregular CT

5

Human Skin

3 Layers

Epidermis

Dermis

Hypodermis

Adipose & loose CT

Vascularized and

innervated

Connects skin to muscle

6

Comparison of Misc. Vertebrate Skins

Mammals

Hair

Reptiles

Scales

Amphibians

Glands

Birds

Feathers, scales

7

SKELETAL SYSTEMS

Common function

Support for body movement

8

Types of Skeletal Systems

Hydrostatic skeleton

Muscles work against

internal body fluids

(incompressible)

9

Types of Skeletal Systems

Exoskeleton

Rigid external parts

10

Types of Skeletal Systems

Endoskeleton

Rigid internal parts

11

Vertebrate Skeleton

Bones & cartilage

Functions

Protection

Support

Movement

Mineral storage

Blood cell formation

12

Human Skeleton

Axial skeleton

Forms body axis

80 bones

Appendicular

skeleton

Forms body

appendages

126 bones

Cartilages

13

Bone Structure

Compact bone

Dense framework

Strength

Outer covering

Shafts of long bones

Medullary cavity

Yellow marrow in adults

Fat storage

14

Bone Structure

Compact bone

Spongy bone

“Sponge-like” framework

Ends of long bones

Center of short, flat & irregular

bones

Red marrow

Produces blood cells

15

Bone Structure

Periosteum

Osteon

Central canal

Lacunae

Osteocytes

Lamellae

Canaliculi

16

Long Bone Formation

Hyaline cartilage

Blood vessel invasion

Production of bone

tissue (replaces

cartilage)

Remodeling

Formation of shaft

Continual formation

at ends (epiphysial

plates)

17

Osteoporosis

Result of…

Nutritional imbalance

Lack of exercise

Vices

Hormonal imbalance

18

Joints

Fibrous

Sutures

Immobile

E.g., skull plates

19

Joints

Fibrous

Cartilaginous

Limited movement

Shock absorption

E.g., ribs (costal

cartilage), intervertebral

disks

20

Joints

Fibrous

Cartilagenous

Synovial

Cartilage separated by fluid

filled cavity

Freely moveable

Bones opposite joint linked

by ligaments

E.g., knee, fingers, shoulder

21

MUSCULAR SYSTEM

Skeletal muscles

Provide force to move bones

Attached to bones by tendons

Do 1 thing…contract

Provide movement

Stabilize joints

22

Muscle Action

Antagonists vs. synergists

23

Muscle Action

Flexors vs. extensors

extension flexion

24

Muscle Action

Origin vs. insertion

origin

insertion

25

Muscle Structure

Muscle

Fascicle

Bundles of muscle fibers

Muscle fiber

= muscle cell

Myofibril

Bundle of contractile filaments

Myofilaments

Actin

Myosin

26

Myofibril

Sarcomere = individual contractile unit

Striations

Banding

patterns

A band

I band

sarcomere sarcomere

Z line Z line Z line

27

Myofilaments

Actin & myosin

Individual contractile protein fibers

Muscle Contraction

Sliding filament

process

relaxed

contracted

sliding_filament_theory 29

Sliding Filament Process

Exposure of myosin

binding sites on actin

Requires calcium

Attachment

Power stroke

Detachment

Requires ATP

“Cocking” of the myosin

head

sliding filament 30

Calcium & Exposure of Myosin Binding Sites

Myofibrils surrounded by

sarcoplasmic reticulum

Stores calcium

31

Calcium & Exposure of

Myosin Binding Sites

Ca2+ release

Initiated by nerve impulse

Modifies arrangement of

actin filaments

Enables binding of myosin

heads

32

control of muscles

Muscle Control

33