CHAPTER 4: SUPPORT AND MOVEMENT B. Short Questions Answers

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CHAPTER 4: SUPPORT AND MOVEMENT
B. Short Questions Answers

i) What are the main functions of skeleton?
Ans: FUNCTIONS OF SKELETON:

1. Support and Shape:
   It provides supporting frame work of the body, it gives the body a particular shape.
   
   
2. Protection:
   Bones protect critical internal organs, such as brain spinal cord, heart, lungs and reproductive organs.
   
   
3. Movement:
   Skeletal muscles attached to the bones help move the body.
   
   
4. Mineral Homeostasis:
   Bones serve as depository for calcium, phosphorus, sodium and potassium. Bones can release or take up minerals through negative feed back mechanisms to maintain the homeostasis.
   
   
5. Blood Cell Production:
   Red and white blood cells are produced in bone narrow.

ii) Distinguish between bone and cartilage.
Ans: Difference Between Bone And Cartilage:

S.NO.	Bones	Cartilage
1.	Bones are the hard, inelastic and a tough organ that forms part of the vertebral skeleton.	Cartilage is a soft, elastic and flexible connective tissue that protects the bone from rubbing against each other.
2.	Bones are of two types: compact or spongy.	Cartilage is of three types: Hyaline cartilage, fibrocartilage and elastic cartilage.
3.	Bone cells are known as osteocytes.	Cartilage cells are known as chondrocytes.
4.	Presence of blood vessels.	Absence of blood vessels
5.	Has deposits of calcium salts.	May or may not have deposition of calcium salts.
6.	The bones have a rich blood supply.	Lacks blood supply (hence repair is slower)
7.	Protect the body from mechanical damage, provide a framework and shape for the body, helps in the movement of the body, store minerals, and produce both RBC – red blood cells and WBC – white blood cells.	Supports the respiratory tract, acts as shock absorbers between weight-bearing bones, maintains the shape and flexibility of fleshy appendages and reduces friction at joints.

iii) Locate the cartilages in different organs.
Ans: Cartilage is a connective tissue found in many areas of the body including:

• Joints between bones e.g. the elbows, knees and ankles
• Ends of the ribs
• Between the vertebrae in the spine
• Ears and nose
• Bronchial tubes or airways.

iv) Enlist the name and number of bones present in hind limb.
Ans: The number of bones present in the hind limb is altogether 30 . Their detail is as follows:

• Femur (thigh bone – the longest bone),
• Tibia
• Fibula
• Patella
• Tarsals (ankle bones – 7 in number),
• Metatarsals (5 in number)
• Phalanges (digits – 14 in number).

v) Locate the immovable joints in the human body.
Ans: Immovable joints are called Synarthroses. These include:

• Skull sutures i.e. 8 bones of skull
• The articulations between the teeth and the mandible
• The joint found between the first pair of ribs and the sternum.
• 3 bones of pelvic girdle

vi) Draw neat and labeled diagram of hinge joint and ball and socket joint.
Ans: Labelled Diagram Of Hinge Joint

KNEE JOINT

ELBOW JOINT

Labelled Diagram Of Ball And Socket Joint

vii) What is Rickets? Give its causes.
Ans: Rickets:

• Rickets is a skeletal disorder which is most common in children.
• It results in bowed legs and deformed pelvis.
• It includes the softening and weakening of bones.

Causes:

• It is caused by deficiency of calcium in diet or extremely prolonged vitamin D deficiency. Vitamin D plays vital role in the absorption of Ca⁺⁺, deficiency of vitamin D leads to deficiency of Ca in bone.
• Mainly it is caused by a lack of vitamin D, calcium, or phosphate.
• These nutrients are important for the development of strong, healthy bones.
• People with rickets may have weak and soft bones, stunted growth, and, in severe cases, skeletal deformities.

viii) Distinguish between ligament and tendon.
Ans: Difference Between Ligament And Tendon:

S.NO.	Tendons	Ligaments
1.	A tendon is a tough fibrous connective tissue that connects muscle to bone.	A ligament is a fibrous connective tissue that connects bones to other bones.
2.	Tough and elastic.	Elastic.
3.	Connects the end of the muscles to bones.	Connects the end of the bones at joints.
4.	Each muscle contains only one tendon.	Each joint contains many ligaments.
5.	White in colour.	Yellow in colour.
6.	Blood supply is poor.	Blood supply is just as poor.
7.	Fibroblasts lie in a continuous row.	Fibroblasts are scattered.
8.	The fibres are compact and present in parallel bundles.	They are not arranged in parallel bundles but are compactly packed.
9.	No such classification.	They are classified into three types, namely: Articular ligaments, Remnant ligaments and Peritoneal ligaments.

ix) Locate hinge joint in the body of human? and also describe its movement?
Ans: Location Of Hinge Joint
The hinge joints of the body include:

• The elbow,
• Knee,
• Interphalangeal (IP) joints of the hand and foot

The tibiotalar joint of the ankle.

Movement Of Hinge Joint:
Hinge joints move back and forth like the hinge on a door and allow movements in one plane only.

x) What do you mean by bicep and triceps muscles?
Ans: The biceps and triceps are two major muscle groups of our arm that play a significant role in the movement of the upper extremities.
Well-developed biceps and triceps are highly sought after by bodybuilders and recreational gym-goers alike.

BICEP MUSCLES:
The bicep muscle is a large muscle that lies on the front of the upper arm between the shoulder and elbow. It has two heads or origin.

Function:
The functions of the biceps include :

• Flexion of the elbow joint. This involves bringing our forearm toward our body.
• Forearm supination. This means turning our palm to face upward.
• Shoulder elevation. This means raising our arm.

Generally, the biceps are the smaller of the upper arm muscles, second to the triceps.

TRICEP MUSCLES:
The tricep is also a large muscle on the back of arm. It is three headed or origin. 

Funtion:
The functions of the triceps include:

• Extension of elbow. This includes moving the forearm away .
• Stabilizing shoulder. For example, when carrying things overhead.
• Shoulder extension. This includes moving our arm back and behind our body.

The triceps serve as an antagonist, or opposing, muscle of the biceps.

More Short Question And Answers

xi) Define following terms?
Irritability, stimuli
Ans: Irritability:
The cells of an organism have a living material, protoplasm,which is sensitive, due to its sensitive nature it possess special property called irritability.

Stimuli:
The change in environment takes place due to some factors these factors are called stimulus (stimuli: p).

xii): Prove that skeleton provide support and movement?
Ans: Skeleton Provide Support and Movement:
Person Stand Straight:
Skeleton provides support to the body, especially limbs. i.e: Hind Limbs and pelvic girdle provide support to the human body to be a bipedal animal, with these limbs the complete vertebrae of vertebral column provide support to stand straight.

Cartilage Gives Support And Proper Shape To Organs As:

• Cartilage of external pinna and nose support the organs to make their proper shape.
• Cartilages also support larynx, trachea and bronchi of respiratory system.
• It forms tough pads which acts as shock absorbers found in knee joints and also form intervertebral discs between vertebrae of backbone.

xiii) Locate Ball and socket joint in the body of human? and also describe its movement?
Ans: Location Of Ball And Socket Joint
The ball and socket joints include:

• Hip joints and
• Shoulder joints

Movement Of Ball And Socket Joint:
This joint allows movement in all directions.
The ball of humerus and femur fit into the socket of pectoral and pelvic girdle respectively.