Transcript Protection, Support & Locomotion

Protection, Support &
Locomotion
Chapter 34
 Skin
has 4 types of
tissues:
 1. Epithelial - covers
surface of body
 2. Connective tough and flexible
protein fibers, holds
the body together
 3. Muscle – interact
with hairs on the skin
to respond to stimuli
 4. Nervous – helps
detect external stimuli
as pain or pressure
Skin composed of 2 layers:

1.
Epidermis –
 outermost
layer, 25-30
layers of dead cells,
 keratin : a protein called
which protects and gives
elasticity
 melanin : inner layer
contains – pigment that
colors skin and protects
from sun
Skin composed of 2 layers:
2. Dermis – inner, thicker
portion of the skin which
contains:
 blood vessels
 Nerves & nerve endings
 hair follicles
 sweat and oil glands
 subcutaneous fat - various
amounts of fat lie under the
dermis
Functions of the Skin:
 1. Thermoregulation –
temperature control
 2. Sensory organ –
pressure, pain,
temperature
 3. Produces essential
vitamins – Vitamin D
 4. Protective layer –
physical and chemical
shield
Skin Facts!
The Skin
Is the body’s largest organ
Makes up about 16% of our total body weight
Every 24 hours, the surface of the skin sheds a
layer of dead cells, constantly renewing about every
28 days
Dead skin cells make up about 90% of household
dust
An average of 40 kilos of skin is shed during a
lifetime
Varies in thickness from 1mm on eyelids to 3mms
on palms and soles
Skin Injury and Healing
injury – fills
with deeper epidermal
cells through cell
division
 Dermis Injury –
bleeding occurs, clots
form, scab covers site,
WBC invade the area to
clean up the mess
 Scaring occurs due to
connective tissue being
laid down on severe
damage/gaps to skin
 Epidermis
BURNS
Amazing Skeleton Facts
Smallest bones are found in the ear.
Longest bone in the body is the femur
Bones are filled with a fatty substance
called bone marrow
In Bone marrow, red and white blood cells
are manufactured and then released into the
bloodstream.
Over half the body's bones are in the hands
and feet
The only jointless bone in your body is the
hyoid bone in your throat.
Skeletal System- 206
Two
systems:
1. Axial (green)
skull, vertebrae,
ribs and the
sternum
2. Appendicular
(Purple) - arms,
legs, shoulder
and hip
 Joints
- point
where 2 bones
meet
 Ligament - fibrous
structure that
connects bone to
bone
 Tendon
-
connective tissue
that connects
muscle to bone
 Bursae - fluid filled
sacs to protect
bones/tendons
Functions of the skeleton
Protect – internal organs & Support –
Move – muscular attachments, levers
Cells - produce blood cells, store
Storehouse
essential
Did you–
know
that humans andminerals,
giraffes
have the same number of bones
in their necks? Giraffe neck vertebrae
are just much, much longer!
fat
Ca
 Did
you know that
humans and
giraffes have the
same number of
bones in their
necks?
 Giraffe neck
vertebrae are just
much, much
longer!
11/10/09
Bone Tissue
 Bones
are porous, these pores contain living
cells and channels for blood vessels that
supply the cells with nutrients. The pores
make bones lighter.
 2 Types:
 1. Spongy or Cancellous bone tissue
 contains many large spaces filled with
marrow (storage for marrow)
 2. Compact or Dense bone tissue
 contains few spaces, it is deposited in a
layer over the spongy bone tissue
Diaphysis Shaft or long main portion,
hollow, covered in compact
bone
 Epiphysis
 Extremities or ends of the
bones, bulbous in shape to
provide muscle attachment
 Metaphysis
 growing portion of the bone
 Articular Cartilage
 Thin layer of hyaline
cartilage covering the
epiphysis (cushions and
protects)

Types of Joints
Go
to page 931 in
your book
Draw and give an
example of the 4
types of joints
1. Hinge
2. Ball & Socket
3. Gliding
4. Pivot
Types of Joints
 Gliding
- (arthrodia),
 flat articulating surfaces
side to side and back and
forth movements
 (Flex/Ext and Ab/ad)
 2 planes - biaxial
 Ex: carpal, tarsal bones,
sternum, clavicle, scapula
 Hinge -(ginglymus) convex surface fits into the
concave surface
 single plane motion
(monaxial) flex/ext
 Ex: elbow, knee, ankle &
interphalangeal joints
 Ball
and Socket - (spheroid) ball like surface
fits into a cup like depression
 (triaxial)moves in 3 planes flex/ext, ab/ad and
rotation
 Ex: hip and shoulder
 Pivot - “twist” on each other, C1-C2, radioulnar joint
Weird Muscle Facts!
 Flea's
can jump 130 times higher
than their own height. In human
terms this is equal to a 6ft. person
jumping 780 ft. into the air
 Hummingbirds are the only animals
able to fly backwards
 A cat has 32 muscles in each ear
Muscular >600

Three Types of muscle
fibers:
 1. Smooth muscle involuntary, non-striated,
blood vessels, digestive
and reproductive tract
 2. Cardiac muscle involuntary, striated, has
own electrical conduction
system, heart
 3. Skeletal muscle voluntary, striated,
muscles for movement
 muscle
fibers - myofibrils - smaller protein
filaments either:
 actin
- thinner filaments
 myosin- thicker filaments
 sarcomeres - sections of the functional units of
muscle
 ATP
supplies muscles in aerobic and
anaerobic exercises
 Sliding filament theory - actin filaments
within a sarcomere slider toward one
another shortening the sarcomere and
causing the muscle to contract