Transcript Support and Movement

Support and Movement
Biology
14.2 Support in mammals
in mammals
skeleton
muscular
system
Contents
Why do organisms need a skeleton?
How are plants supported?
What are skeletal tissues?
Multiple choices
Two parts of skeleton
Joints and degree of movement
What is skeletal muscles?
How is movement achieved?
Why do organisms need a
skeleton?

Contents
Mammals have endoskeletons
•for producing blood cells
Do you know
what is the
deficiency
disease of
calcium?
•for support
Why do organisms need a
skeleton?
•for movement
Contents
Lungs
Heart
•for protection
Contents
Why do organisms need a
skeleton?
•for storage of minerals
Ca2+
Ca2+
Why?
acid
If the bone is immersed in an acidic solution
for about 2 days, what will happen?
Contents
Summary

The mammalian skeleton is important in
support, for attachment of muscles and
functioning as a lever for movement, in
protecting internal organs, in producing
blood cells and in storage of calcium.
Contents
What are skeletal tissues?

The skeletons are made up of bones and
cartilages.
?
Transverse section of a
compact bones
Structure of cartilage
Which one contains more mineral salts?
The skeleton
Skeleton consists of :
bones
• hard
• made up
mainly of
minerals
e.g. calcium
phosphate,
calcium
carbonate
cartilage
• found
between
bones
• softer
• reduces
friction
during
movement
Contents
What are skeletal tissues?
Cartilage
Spongy bone containing
red bone marrow.
Compact bone
Cavity containing yellow
bone marrow
Contents
What are skeletal tissues?
If my bones are burnt, it
will become brittle.
Contents
Two parts of skeleton
Axial
skeleton
Appendicular
skeleton
Contents
Two parts of skeleton
Axial skeleton
•
•
•
•
Skull
Sternum
Ribs
Vertebral
column
Appendicular skeleton
•
Pectoral girdles
•
Pectoral limbs
•
Pelvic girdles
•
Pelvic limbs
Correct Posture to Prevent Injury
•Plant your feet firmly - get a stable base.
•Bend at your knees - not your waist.
•Tighten your abdominal muscles to
support your spine.
•Get a good grip - use both hands.
•Keep the load close to your body.
•Use your leg muscles as you lift.
•Keep your back upright, keep it in its
natural posture.
•Lift steadily and smoothly without jerking.
•Breathe - If you must hold your breath to
lift it, it is too heavy.
DO NOT...
•Lift from the floor.
•Twist and lift.
•Lift with one hand (unbalanced)
•Lift loads across obstacles.
•Lift while reaching or stretching.
•Lift from an uncomfortable posture.
•Don't fight to recover a dropped
object.
•Don't hold your breath while lifting GET HELP.
The muscular system
muscular system
• many different
tendons
sets of muscles
• the two ends of • tough sheets
of inelastic
each muscle are
fibres
attached to the
• allow muscles
limb bones
to control the
through tendons
way bones
move
Muscles are attached to
bones through tendons
Joints and degree of
movement
• Synovial

Contents
Joint
1. Hinge joints
Hinge joints allow movement in one plane.
Joints and degree of
movement
Contents
2. Ball-and-socket joints
How many
planes of
movement do
ball-an-socket
joints allow?
Joints and degree of
movement

Contents
2. Ligaments are tough and they prevent
dislocation of a joint during movement.
pelvic girdle
ligaments
cartilage
femur
synovial
joint
synovial
membrane
Contents
What are skeletal muscles?

Muscle attached to the skeleton. Muscle cells
Muscles
contract
with lots
of proteins
fibres
powerfully—ie. They
 Muscles work together with bones to give
work by PULLING. Do
support and movement to mammals.
you think muscles can
stretch themselves—and
In aerobic respiration:
thus work by
PUSHING?
In anaerobic respiration:
Support in mammals
in mammals
skeleton
muscular
system
The muscular system
Muscles as part of the support system
If the forces of
the muscles
acting on both
sides of two
adjacent
bones are
balanced
bones will be kept in
the same position
A skeleton falls down
if let loose because
nothing joins the bones
together
Skeleton without muscles………..
give no
support !!
How is movement
achieved?

Contents
1. Tendons are tough and they connect
muscles to bones.
muscle
tendons
How is movement
achieved?

Contents
2. Biceps and triceps are antagonistic
muscles involved in the movement of the
forearm. They work in pairs and in
opposing directions.
How is movement
achieved?

Contents
3. Contraction of biceps (flexor) bends the
forearm while contraction of triceps
(extensor) straightens the forearm.
triceps
relaxes
biceps
contracts
triceps
contracts
biceps
contracts
How is movement
achieved?
Contents
How is movement
achieved?

Contents
4. Bone act as levers during movement.
Movable joints act as the fulcrum.
Concentration of muscles creates the effort.
contraction of
biceps (effort)
elbow joint
hand (load)
(fulcrum)
Contents
How are plants supported?

1. Support in young plants or non-woody
parts of plants is contributed mainly by
turgidity of the thin-walled cells in the
cortex and pith.
14.3 Support in plants
in plants
Turgidity of cells
For non-woody
plants
Hardness of thickwalled cells in
woody plants
Turgidity of cells
Inside stem of herbaceous plants-(non-woody)
If adequate water supply,
water
water
potential of > potential of
xylem
living cells
Cells become
turgid
water move
from xylem to
living cells in
stems
Turgid cells press against each
other to give support to the plant
Turgidity of cells
Inside stem of herbaceous plants
If inadequate water supply,
water
water
potential of < potential of
xylem
living cells
The plant wilts
Cells become
flaccid
Flaccid cells cannot provide
support to the plant
The hardness of thick-walled cells
Plants are also supported by
thick-walled cells
mostly xylem cells
which contain lignin
As plant grows, older xylem
tissues in stems are pushed
inwards and become wood.
Contents
How are plants supported?
Water absorbed
by osmosis
turgid
Water lost by
osmosis
flaccid
In this case,
transpiration is
faster than
absorption of
water.
Wilting occurs
Contents
How are plants supported?

2. Support in woody stems is contributed
mainly by rigidity of the lignified cells in
xylem.
Contents
Multiple choices
1. Which muscles contract to
effect a change form the
condition shown in Diagram I to
that in Diagram II?
P, Q and R
P, Q and S
P, R and T
Q, S and T
Contents
Multiple choices
2. Which of the following functions are carried
out by bone W?
(1) Producing red blood cells
(2) helping in ventilation of the lung
(3) protecting internal organs
(1) and (2) only
(1) and (3) only
(2) and (3) only
(1), (2) and (3)
Contents
Multiple choices
3. Which of the joints X, Y and Z allow(s)
movement between the bones?
Y only
Z only
X and Y only
Y and Z only
Contents
Multiple choices
4. Which of the following
correctly describes
the functions of
structures A and B?
Structure A
Structure B
holding the bones
together
acting as a pivot
protecting the joint
transmitting force
to the bone
protecting the joint
preventing dislocation of
the joint
acting as a pivot
transmitting force
to the bone
Contents
Multiple choices
5. The diagram below shows a man at a certain stage of
swimming:
Which of the following combinations correctly describes the
conditions of his arm muscles at this stage?
Left arm
Right arm
Biceps
Triceps
Biceps
Triceps
contracted
relaxed
relaxed
contracted
relaxed
contracted
contracted
relaxed
contracted
relaxed
contracted
relaxed
relaxed
contracted
relaxed
contracted
Contents
Multiple choices
6. The diagram below shows a human arm holding a weight:
The length of EF is shorter
than the length of WF. What is
the advantage of this
arrangement?
The biceps would not become fatigue easily.
This would make the biceps stronger than the triceps.
Less energy would be used by the biceps in supporting the weight.
A small contraction of the biceps would move the weight through a
large distance.
Contents
Multiple choices
7. Which structures are parts of the axial skeleton?
1, 2 and 3
1, 2 and 4
1, 3 and 4
2, 3 and 4
3
Contents
Multiple choices
8. Which of the following correctly lists the structures
protected by the different parts of the skeleton?
1
2
3
brain aorta
stomach
ears
heart
aorta
brain spinal cord heart
ears
spinal cord
stomach
3
Contents
Multiple choices
9. The diagram below shows a model of a movable joint:
Which of the following combinations
is correct?
Type of joint
represented by the model
Example
hinge joint
knee joint
hinge joint
shoulder joint
ball and socket joint
ball and socket joint
shoulder joint
Knee joint
Contents
Multiple choices
10. The diagrams below show three sets of bones of the
human skeleton:
1
Ball and socket joint can be formed between
1 and 3.
1 and 4.
2 and 3.
2 and 4.
Contents
Multiple choices
The model below illustrate the movement at the elbow joint:
11. Which of the following occurs when Q is shortened?
P
S
shortened
raised
shortened
lowered
stretched
raised
stretched
lowered
Contents
Multiple choices
The model below illustrate the movement at the elbow joint:
12. The model is useful for demonstrating
the movement of the upper arm.
that the joint allows 360º movement.
that the biceps is stronger than the triceps.
the actions of a pair of antagonistic muscles.
Contents
Multiple choices
Diagram I shows some muscles attached to the leg bones.
Diagram II shows the posture of a person sitting on a stool.
1
13. Which muscles in the
person’s leg are
contracted when he
maintains the posture
shown in the diagram II?
muscles 1 and 2 only
2
muscles 1 and 3 only
muscles 2 and 4 only
muscles 3 and 4 only
Contents
Multiple choices
14. Which of the following are involved in maintaining our
postures?
(1) skeletal muscles
(2) bones
(3) ligaments
(4) nervous system
(1) and (2) only
(3) and (4) only
(1), (2) and (3) only
(1), (2), (3) and (4)
Contents
Multiple choices
14. Which of the following is not a function of the mammalian
skeleton?
storage of fat
storage of calcium
destruction of red blood cells
production of white blood cells
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