Transcript Prentice Hall Biology - Cathedral High School

Chapter 36 Skeletal, Muscular
and Integumentary Systems
1
Section Outline
Section 36-1
I. The Skeletal System
A. The Skeleton: two subdivisions: Axial and Appendicular
1. Functions
a. supports the body
b. protects internal organs (brain and internal
organs
c. provides for movement (levers for muscles
to act on)
d. stores minerals (calcium)
e. site for red blood cell production (produced
in red marrow)
2
The Skeletal System
Section 36-1
Skull
Axial
Skeleton
Clavicle
Sternum
Scapula
Humerus
Ribs
Radius
Pelvis
Ulna
Carpals
Metacarpals
Vertebral
column
Phalanges
Femur
Patella
Fibula
Tibia
Tarsals
Metatarsals
Phalanges
3
Appendicular
Skeleton
B. Structure
of Bones - a solid network of living cells
Section
Outline
and protein fibers, surrounded by calcium mineral salts
Section 36-1
1. periosteum – a tough layer of connective tissue
surrounding a bone
2. Haversian canals – a network of tubes running
through compact bone that carry blood vessels
3. spongy bone – strong but light bone found and the
ends of long bones, and between compact
bone in ribs and skull bones
4. bone cells- three types
a. osteocytes – mature bone cells that maintain
bone structure
b. osteblasts – create new bone tissue
c. osteoclasts – break down bone
4
Figure 36-3 The Structure of Bone
Spongy bone
Haversian
Compact
canal
bone
Compact bone
Periosteum
Bone
marrow
Spongy bone
Osteocyte
Artery
Periosteum
Vein
5
Section Outline
Section 36-1
C.
Development of Bones
1. embryonic skeletons are composed of cartilage
2. cartilage is replaced by bone during embryonic
development
3. the process of replacement is called ossificaton
4. in early adulthood all the cartilage is replaced by
bone (ossification)
6
Section 36-1
D. Types of Joints
1. Immovable Joints – allow no movement – skull bones
2. Slightly Movable Joints – allow some movement –
between bones of lower leg, and between vertebrae
3. Freely Movable Joints – movement in one or more
directions
a. ball and socket joint –movement in many
directions (shoulder and hip)
b. hinge joint – movement in one direction (knee
and elbow)
c. pivot joint – one bone rotates around another
(lower arm)
d. saddle joint – bones slide in two directions
(between wrist and hand)
7
Figure 36-4 Freely Movable Joints and Their
Movements
Ball-and-Socket Joint
Pivot Joint
Clavicle
Humerus
Ball-andsocket
joint
Radius
Pivot
joint
Hinge Joint
Scapula
Saddle Joint
Ulna
Humerus
Femur
Patella
Fibula
Metacarpals
Tibia
Hinge
joint
Saddle joint
8
Carpals
E. Structure
of joints and skeletal disorders
Section
Outline
Section 36-1
1. ends of bones in freely moveable joints are covered
with cartilage for protection
2. the joint is surrounded by a tough joint capsule that
has two layers
a. ligaments are strips of connective tissue
that hold bones together and stabilize the
joint
b. the other layer produces synovial fluid,
which lubricates the joint
3. bursa are small sacs found in a joint that reduce
friction and act as cushions
4. Skeletal System Disorders
a. bursitis – inflammation of the bursa
b. osteoporosis – a loss of calcium from
bones which causes them to weaken
9
Figure 36-5 Knee Joint
Section 36-1
Muscle
Tendon
Femur
Patella
Bursa
Ligament
Synovial fluid
Cartilage
Fat
Fibula
Tibia
10
Section Outline
Section 36-2
II. Muscular System– causes movement of body parts and
materials
A. Types of muscle tissue
1. skeletal – connected to the skeletal system
a. striations – alternating light and dark bands
seen under a microscope
b. under voluntary nervous control
c. have many nuclei in each cell
2. smooth muscle – located in internal organs
a. no striations present
b. involuntary nervous control
3. cardiac muscle – found in the heart
a. striations present
b. involuntary nervous control
11
Section Outline
Section 36-2
B. Muscle Contraction
1.muscle cells are made up of 2 fibers called myofibrils
a. a thin filament called actin
b. a thick filament called myosin
2. a muscle contraction happens when actin and myosin
slide past each other
3. actin and myosin form cross bridges between them
which allows a contraction to take place
4. ATP is used to power the reactions that cause
contraction
C. Control of Muscle contractions
1.skeletal muscle contraction is controlled by the nervous
system
2. a nerve ending connects to each muscle cell at a
neuromuscular junction
12
Section Outline
Section 36-2
3.when a nervous impulse is sent down a nerve, a
chemical is released that causes contraction to begin
a. acetylcholine is the neurotransmitter that is
released
D. Muscle and Bone interaction
1.muscles can only contract, so they are arranged in
opposing pairs
2. muscles connect to bones by connective tissue strips
called tendons
13
Cycle Diagram
1
Myosin forms
cross-bridge
with actin
5
2
Myosin returns
to original
shape
Cross-bridge
changes
shape
4
3
Cross-bridge
releases actic
Actin pulled
14
Figure 36-7 Skeletal Muscle Structure
Section 36-2
15
Figure 36-8 Muscle Contraction
Section 36-2
Relaxed Muscle
Z line
Myosin
Actin
Z line
Movement of Actin Filament
Actin
Sarcomore
Contracted Muscle
Cross-bridges
Crossbridge
Binding
sites
Myosin
Z line
16
Figure 36-8 Muscle Contraction
Section 36-2
Relaxed Muscle
Z line
Myosin
Actin
Z line
Movement of Actin Filament
Actin
Sarcomore
Contracted Muscle
Cross-bridges
Crossbridge
Binding
sites
Z line
Myosin
During muscle
contraction, the
knoblike head of a
myosin filament
attaches to a binding
site on actin, forming
a cross-bridge.
16
Figure 36-8 Muscle Contraction
Section 36-2
Relaxed Muscle
Z line
Myosin
Actin
Z line
Movement of Actin Filament
Actin
Sarcomore
Contracted Muscle
Cross-bridges
Crossbridge
Binding
sites
Z line
Myosin
During muscle
contraction, the
knoblike head of a
myosin filament
attaches to a binding
site on actin, forming
a cross-bridge.
16
Powered by ATP,
the myosin crossbridge changes
shape and pulls
the actin filament
toward the center
of the sarcomere.
Figure 36-8 Muscle Contraction
Section 36-2
Relaxed Muscle
Z line
Myosin
Actin
Z line
Movement of Actin Filament
Actin
Sarcomore
Contracted Muscle
Cross-bridges
Crossbridge
Binding
sites
Z line
Myosin
During muscle
contraction, the
knoblike head of a
myosin filament
attaches to a binding
site on actin, forming
a cross-bridge.
16
Powered by ATP,
the myosin crossbridge changes
shape and pulls
the actin filament
toward the center
of the sarcomere.
The cross-bridge is
broken, the myosin
binds to another
site on the actin
filament, and the
cycle begins again.
Figure 36-11 Opposing Muscle Pairs
Opposing Muscle Pairs
Movement
Movement
Biceps (relaxed)
Triceps (relaxed)
Biceps (contracted)
Triceps (relaxed)
17
Section 36-3
III. Integumentary System: Skin, hair, nails and several glands
A. Functions
1. a barrier against infection and injury
2. helps regulate body temperature
3. removes waste products
4. provides protection from ultraviolet light
18
Section 36-3
B. Two main layers: Epidermis and Dermis
1. epidermis – upper layer of skin
a. top layer of skin is dead, and made up of a
waterproofing protein called keratin
b. deeper layer is living and produces a dark
pigment called melanin (UV protection)
c. the epidermis is avascular (no blood vessels)
2. dermis – contains blood vessels, nerve endings, hair
follicles, glands, and smooth muscle
a. blood vessels help to regulate heat loss and gain
b. glands produce sweat and oils to cool the body
and keep the skin flexible and waterproof
19
Concept Map
Section 36-3
Skin
functions
as a
Barrier to
infection
Regulator of
body
temperature
is made
up of the
Protector
against UV
radiation
Remover of
waste products
Epidermis
which
is the
Outer layer
20
Dermis
which
is the
Inner layer
Figure 36-13 The Structure of Skin
Section 36-3
21
5
Video 2
5