Samacheer Kalvi 11th Bio Zoology Guide Chapter 9 Locomotion and Movement

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Zoology Guide Pdf Chapter 9 Locomotion and Movement Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Zoology Guide Chapter 9 Locomotion and Movement

11th Bio Zoology Guide Locomotion and Movement Text Book Back Questions and Answers

Part I

Question 1.
Muscles are derived from
a) ectoderm
b) mesoderm
c) endoderm
d) neuroectoderm
Answer:
b) mesoderm

Question 2.
Muscles are formed by
a) myocytes
b) leucocytes
c) osteocytes
d) lymphocytes
Answer:
a) myocytes

Question 3.
The muscles attached to the bones are called
a) skeletal muscle
b) cardiac muscle
c) involuntary muscle
d) smooth muscles
Answer:
a) skeletal muscle

Question 4.
Skeletal muscles are attached to the bones by
a) tendon
b) ligament
c) pectin
d) fibrin
Answer:
a) tendon

Question 5.
The bundle of muscle fibers is called
a) Myofibrils
b) fascicle
c) sarcomere
d) sarcoplasm
Answer:
b) fascicle

Question 6.
The pigment present in the muscle fiber to store oxygen is
a) myoglobin
b) troponin
c) myosin
d) actin
Answer:
a) myoglobin

Question 7.
The functional unit of a muscle fibre is
a) sarcomere
b) sarcoplasm
c) myosin
d) actin
Answer:
a) sarcomere

Question 8.
The protein present in the thick filament is
a) myosin
b) actin
c) pectin
d) leucine
Answer:
a) myosin

Question 9.
The protein present in the thin filament is
a) myosin
b) actin
c) pectin
d) leucine
Answer:
b) actin

Question 10.
The region between two successive Z-discs is called a
a) sarcomere
b) microtubule
c) myoglobin
d) actin
Answer:
a) sarcomere

Question 11.
Each skeletal muscle is covered by
a) epimysium
b) perimysium
c) endomysium
d) hyponychium
Answer:
a) epimysium

Question 12.
The knee joint is an example of
a) saddle joint
b) hinge joint
c) pivot joint
d) gliding joint
Answer:
b) hinge joint

Question 13.
The name of the joint present between the atlas and axis is
a) synovial joint
b) pivot joint
c) saddle joint
d) hinge joint
Answer:
b) pivot joint

Question 14.
ATPase enzyme needed for muscle contraction is located in
a) actinin
b) troponin
c) myosin
d) actin
Answer:
c) myosin

Question 15.
Synovial fluid is found in
a) Ventricles of the brain
b) Spinal cord
c) immovable joint
d) freely movable joints
Answer:
d) freely movable joints

Question 16.
Inflammation of joints due to accumulation of uric acid crystals is called as
a) Gout
b) myasthenia gravis
c) osteoporosis
d) osteomalacia
Answer:
a) Gout

Question 17.
The acetabulum is located in
a) collar bone
b) hip bone
c) shoulder bone
d) thigh bone
Answer:
b) hip bone

Question 18.
Appendicular skeleton is
a) girdles and their limbs
b) vertebrae
c) skull and vertebral column
d) ribs and sternum
Answer:
a) girdles and their limbs

Question 19.
The type of movement exhibits by the macrophages are
a) flagellar
b) ciliary
c) muscular
d) amoeboid
Answer:
d) amoeboid

Question 20.
The pointed portion of the elbow is
a) acromion process
b) glenoid cavity
c) olecranon process
d) symphysis
Answer:
c) olecranon process

Question 21.
Name the different types of movement
Answer:

• Amoeboid movement
• Ciliary movement
• Flagellar movement
• Muscular movement

Question 22.
Name the filaments present in the Sarcomere.
Answer:
Thick and thin filaments are the two types of filaments present inside the sarcomere.

Question 23.
Name the contractile proteins present in the skeletal muscle.
Answer:

• Myosin – thick filament
• Actin – Thin filament

Question 24.
When describing a skeletal muscle. What does “Striated mean?
Answer:
Each skeletal muscle fibre has a repeated series of dark and light bands. The dark A-bands and light I-bands give a striated appearance to the muscle.

Question 25.
How does an isotonic contraction take place?
Answer:
In isotonic contraction, the length of the muscle changes but the tension remains constant.
(eg) lifting dumbbells and weight lifting.

Question 26.
How does an isometric contraction take place?
Answer:
In isometric contraction, the length of the muscle does not change but the tension of the muscle changes. The force produced is changed, e.g., pushing against a wall, holding a heavy bag.

Question 27.
Name the bones of the skull.
Answer:
The cranial bones are 8 in number.

1. Paired parietal
2. Paired temporal
3. frontal
4. Sphenoid
5. Occipital
6. Ethmoid

Question 28.
Which is the only jointless bone in the human body?
Answer:
The jointless bone is the hyoid bone in our throat. The hyoid bone (lingual bone) is a horseshoe.

Question 29.
List the three main parts of the axial skeleton.
Answer:

1. Cranium
2. Hyoid (Lingual)
3. Vertebral column
4. Thoracic cavity.

Question 30.
How is tetany caused?
Answer:
Tetany is caused when rapid muscle spasms occur in the muscles due to deficiency of parathyroid hormone resulting in reduced calcium levels in the body.

Question 31.
How does rigor mortis happen?
Answer:
After the death of an individual, the membrane of muscle cells becomes more permeable to calcium ions. This happens due to the partial contraction of skeletal muscles. The contracted muscles are unable to relax. This condition is known as rigor mortis.

Question 32.
What are the different types of rib bones that form the rib cage?
Answer:
Thoracic vertebrae ribs and sternum together constitute the ribcage.

Question 33.
What are the bones that make the pelvic girdle?
Answer:

• Ilium
• Ischium
• Pubis

Question 34.
List the disorders of the muscular system.
Answer:

1. Myasthenia gravis
2. Tetany
3. Muscle fatigue
4. Atrophy
5. Muscle pull
6. Muscular dystrophy

Question 35.
Explain the sliding-filament theory of muscle contraction.
Answer:
Sliding filament theory is an active process. It is proposed by Andrw F. Huxley in 1954 and Rolf Niedergerke.

• Muscle contraction is initiated by a nerve impulse sents by the central nervous system through a motor neuron
• When the nerve impulse reaches neuromuscular junction acetylcholine is released and created action potential.
• This action potential triggers the release of calcium from the sarcoplasmic reticulum
• The released calcium ions bind to troponin on thin filaments.
• The active sites are exposed to the heads of myosin to form a cross bridge. Hence actin and myosin form a protein complex called actomyosin.
• Utilizing the energy released from the hydrolysis of ATP the myosin head rotates until it forms a 90° angle with a long axis of the filament.
• The power stroke begins after the myosin head and hinges region tilt from a 90° angle to a 45° angle.
• The cross-bridge transforms into a strong high force bond which allows the myosin head to swells it.
• When the myosin head swells it pulls the attached actin filament towards the centre of the A – band.
• The myosin returns back to its relaxed state and releases ADP and phosphate ions. A Newer ATP molecule binds to the head of the myosin and the cross-bridge is broken.
• At the end of each power stroke each myosin head detaches from actin then swivels back and binds to a new actin molecule to start another contraction cycle.
• The power stroke repeats many times and the thin filaments move toward the centre of the sarcomere.
• In this process, there is no change in the lengths of thick or thin filaments.
• The Z – discs attached to the actin filaments are also pulled inwards from both sides causing the shortening of the sarcomere. This process continues.
• When motor impulse stops the calcium ions are purnbed back into the sarcoplasmic reticulum results in the masking of the active sites of the actin filament and the myosin head fails to bind with the actin and causes Z – discs back to their original relaxed position.

Question 36.
What are the Benefits of regular exercise?
Answer:

1. The benefits of regular exercise are:
2. The muscles used in exercise grow larger and stronger.
3. The resting heart rate goes down.
4. More enzymes are synthesized in the muscle fiber.
5. Ligaments and tendons become stronger.
6. Joints become more flexible.
7. Protection from a heart attack.
8. Influences hormonal activity.
9. Improves cognitive functions.
10. Prevents obesity.
11. Promotes confidence, esteem.
12. Aesthetically better with a good physique.
13. Overall well-being with good quality of life.
14. Prevents depression, stress, and anxiety.

Part II

11th Bio Zoology Guide Locomotion and Movement Additional Important Questions and Answers

I. Choose The Best Options

Question 1.
Which of the following is not related to skeletal muscle?
(a) It is attached to the bone
(b) It is striated
(c) It is an involuntary muscle
(d) It brings about movement of the organ
Answer:
(c) It is an involuntary muscle

Question 2.
Where is a ciliary movement taking place?
Answer:
a) Respiratory tract
b) Stomach
c) oesophagus
d) Reproductive tract
Answer:
d) Reproductive tract

Question 3.
The cytoplasm of the muscle fibre is ……………….
(a) Sarcolemma
(b) Sarcoplasm
(c) Ectoplasm
(d) Endoplasm
Answer:
(b) Sarcoplasm

Question 4.
Muscles are made up of ………………….
a) Myocytes
b) Lymphocytes
c) adenocytes
d) leucocytes
Answer:
a) Myocytes

Question 5.
The cranial bones are ………………..
(a) 22
(b) 14
(c) 8
(d) 3
Answer:
(c) 8

Question 6.
Name the connective tissue which covers the entire muscle?
a) Epimycium
b) Perimycium
c) Endomyciurn
d) Mesornyscium
Answer:
a) Epimycium

Question 7.
The number of vertebrates is ………………..
(a) 8
(b) 12
(c) 5
(d) 33
Answer:
(d) 33

Question 8.
Name the membrane which covers each muscle fiber?
a) Epimycium
b) Perimycium
c) Endomycium
d) Mesomysciurn
Answer:
c) Endomycium

Question 9.
Match and Find the Correct Pair
1. Sarcoplasm – a) Respiratory pigment
2. Myoglobin – b) Glucose giver
3. Glycosome – c) Unit of skeletal muscle
4. Sarcomere – d) cytoplasm

Answer:
a) I- d, II – a, III – b,IV- c

Question 10.
Find the correct and wrong statement and arrange the following statement.
1. The contraction of muscle fibres depends on the actin and myosin protein.
2. The thick muscle fibres depend on Myosin.
3. Each meromyosin molecule will have a globular head with a long arm.
4. The head of the meromyosin bears an actin-binding site and an ATP binding site.

Answer:
a) True True False True

Question 11.
The joint between carpal and metacarpals is ………………..
(a) Pivot joint
(b) Ball and socket joint
(c) Saddle joint
(d) Hinge joint
Answer:
(c) Saddle joint

Question 12.
Who has proposed sliding – filaments hypothesis?
a) Andrew F. Huxley and Rolf Nieder gerke
b) Andrew F. Huxley and Nelson
c) Andrew F. Pluxley and Darwin
d) Andrew F. Huxley and Mendal
Answer:
a) Andrew F. Huxley and Rolf Nieder gerke

Question 13.
Which of the following disorders is related to the endocrine gland?
(a) Myasthenia gravis
(b) Tetany
(c) Atrophy
(d) Muscular dystrophy
Answer:
(b) Tetany

Question 14.
Find out the wrong pair
a) Fast – oxidative fibres – have high ATP ase activity
b) Slow – oxidative fibres – low rates of ATP ase activity
c) Oxidative fibres – less number of mitochondria
d) Red muscle fibres – oxidative fibres
Answer:
c) Oxidative fibres – less number of mitochondria

Question 15.
Which of the following is deficiency disorder?
(a) Osteoarthritis
(b) Rheumatoid arthritis
(c) Gouty arthritis
(d) Osteoporosis
Answer:
(d) Osteoporosis

Question 16.
………………………… a number of bones from the endoskeleton of man?
a) 210
b) 220
c) 206
d) 209
Answer:
c) 206

Question 17.
Hove many bones are there in the axial and appendicular skeleton?
a) 80 and 126
b) 126 and 80
c) 80 and 120
d) 80 and 118
Answer:
a) 80 and 126

Question 18.
How many bones are there in the facial and cranial bones?
a) 14 and 9
b) 14 and 8
c) 14 and 10
d) 14 and 12
Answer:
b) 14 and 8

Question 19.
Name the opening of the temporal bone
a) External auditory meatus
b) Nasal opening
c) Optic opening
d) Mouth
Answer:
a) External auditory meatus

Question 20.
Name the U-shaped single bone present at the base of the buccal cavity.
a) Palantine bone
b) Hyoid bone
c) Ethmoid bone
d) Sphenoid bone
Answer:
b) Hyoid bone

Question 21.
How many bones from the vertebral column?
a) 33
b) 32
c) 30
d) 36
Answer:
a) 33

Question 22.
Match and find the correct pair
1) Cervical vertebrae – a) – 5
2) Thoracic – b)-l
3) Pelvic bone – 0-7
4) Coccyx bone – d) -12

Answer:
a) I -c, II – d, III – a,IV – b

Question 23.
In which bone ………….. situated?
a) Cervical vertebra
b) thoracic vertebra
c) Pelvic vertebra
d) all the above
Answer:
d) all the above

Question 24.
Name the first vertebra?
a) Atlas
b) Maleus
c) Incus
d) Stapes
Answer:
a) Atlas

Question 25.
Name the second vertebra?
a) Atlas
b) Axis
c) Maleus
d) Stapes
Answer:
b) Axis

Question 26.
How many are the number of ribs?
a) 14 pair
b) 13 pair
c) 12 pair
d) 15 pair
Answer:
c) 12 pair

Question 27.
Match and find the correct answer
1) ribs – a) – 1, 7
2) True ribs – b) -11, 12
3) False ribs – c) – Bicephalic
4) Floating ribs – d) – 8, 10

Answer:
b) I – c, II – a, III – d,IV -b

Question 28.
How many bones are there appendicular skeleton?
a) 130
b) 140
c) 126
d) 122
Answer:
c) 126

Question 29.
Which forms the appendicular skeleton?
a) Upper and hindlimbs
b) Upper limbs and thoracic bones
c) Hind and vertebral column
d) Hind and cranial bones
Answer:
a) Upper and hindlimbs

Question 30.
Name the bones which join the axial and appendicular skeleton.
a) Clavicle bone
b) Scapula
c) Acromian process
d) None of the above
Answer:
a) Clavicle bone

Question 31.
Flow many bones are there in the upper arm.
a) 30
b) 32
c) 34
d) 36
Answer:
a) 30

Question 32.
Find the wrong pair.
a) Wrist bone – 8
b) Fore arm bones – 30
c) Facial bone – 16
d) Cranial bones – 8
Answer:
c) Facial bone – 16

Question 33.
Find the wrong pair
a) Palm bones – 5
b) Phalanges – 14
c) Thoracic bone – 12
d) Vertebral column – 33
Answer:
d) Vertebral column – 33

Question 34.
Match and find the correct pair.
1) Cervical vertebra – a) 12
2) Thoracic vertebra – b) 1
3) Pelvic vertebra – c) 7
4) Coccyx – d) 5

Answer:
a) I- c, II – a, III – d, IV – b

Question 35.
The oxidative skeletal muscle fibres are termed as
a) Fatty muscle fibres
b) White muscle fibres
c) red muscle fibres
d) yellow muscle
Answer:
c) red muscle fibres

Question 36.
Whether the following statement is correct or wrong find out the correct sequence.
1) Pelvic bone Ilium, Ischium, and pubis
2) Acetabulum cavity is present in the sacrum
3) The head of the thigh bone fits in the acetabulum cavity
4) The pubic bones articulate anteriorly at the pubic symphysis
Sequence:
a) 1 – True, 2 – False, 3 – True, 4 – True
b) 1 – False, 2 – False, 3 – True, 4 – True
c) 1 – False, 2 – True, 3 – True, 4 – True
d) 1 – True, 2 – True, 3 – False, 4 – True
Answer:
a) 1 – True, 2 – False, 3 – True, 4 – True

Question 37.
Which is the prominent bone of the pelvic bone?
a) Ilium
b) Ischium
c) Pubis
d) all the above
Answer:
a) Ilium

Question 38.
What is the number of hind limbs?
a) 32
b) 37
c) 30
d) 34
Answer:
c) 30

Question 39.
Name the longest bone
a) Femur
b) Humerus bone
c) Tibia
d) all the above

Answer:
a) I – a, II – d, III – c, IV – b

Question 40.
Match and find the correct pair.
1)Patella – a) 14
2) Tarsus – b) 5
3) Metatarsus – c) 7 bones
4) Phalanges – d) kneecap
Answer:
3) Metatarsus – c) 7 bones

Question 41.
Name the membrane which covers the femur bone.
a) Periosteum
b) Endosteum
c) Osteoclast
d) Osteoblast
Answer:
a) Periosteum

Question 42.
Name the joints seen in the cranial region
a) Fibrous joints
b) Cartilagenous joints
c) Diarthroses joints
d) Synovial joints
Answer:
a) Fibrous joints

Question 43.
The Synovial fluid is seen in joints.
a) Cartilagenous joints
b) Diarthroses joints
c) Fibrous joints
d) all the above
Answer:
b) Diarthroses joints

Question 44.
Name the diseases due to the deficiency of acetylcholine.
a) Myasthenia gravis
b) Tetany
c) Duchene muscular dystrophy
d) Muscle pull
Answer:
a) Myasthenia gravis

Question 45.
Name the disease due to the deficiency of ATP
a) Muscle fatigue
b) Muscle pull
c) Muscular dystrophy
d) Tetany
Answer:
a) Muscle fatigue

Question 46.
A tear in the muscle
a) Muscle fatigue
b) Muscle pull
c) Atrophy
d) Muscular dystrophy
Answer:
b) Muscle pull

Question 47.
Name arthritis due to aging.
a) Osteoarthritis
b) Rheumatoid arthritis
c) Gout
d) Osteoporosis
Answer:
a) Osteoarthritis

Question 48.
Osteoporosis is due to
a) Calcium
b) Sodium
c) Magnesium
d) Potassium
Answer:
a) Calcium

Question 49.
The deposition of urate crystals on the joints is called as
a) Gout
b) Rheumatoid
c) arthritis
d) Osteoporosis
Answer:
a) Gout

Question 50.
Assertion A: Acetylcholine is secreted in the Neuromuscular junction.
Reason B: If acetylcholine is not secreted there won’t be any multiple gated channels in the sarcolemma.
a) A true B wrong
b) A true B this explains the action of A
c) A wrong B true
d) A wrong B wrong
Answer:
b) A true B this explains the action of A

Question 51.
Assertion A: The upper limbs are attached to the pectoral girdles.
Reason B: The pectoral girdles are very light and allow the mobility of the hand
a) A wrong B wrong
b) A True B does not explain the A
c) A True B explains the functions of A
d) A True B wrong
Answer:
c) A True B explains the functions of A

Question 52.
Assertion A: In the pelvis bone a deep socket is present called acetabulum.
Reason B: The head of the femur bone fits in the acetabulum.
a) A True B explains the functions of A
b) A wrong B explains the functions of A
c) A True B wrong
d) B does not explain the structure of B
Answer:
a) A True B explains the functions of A

Question 53.
Assertion A: The pelvis of the female is shallow wide and flexible in nature
Cause B: This helps during pregnancy.
a) A True B explains the functions of A
b) A wrong B explains the functions of A
c) A True B wrong
d) B does not explain the structure of A
Answer:
a) A True B explains the functions of A

Question 54.
Assertion A: The lower arm carries the entire weight of the body and is subjected to exceptional forces when we jump or run.
Reason B: To bear the weight of the body it has 46 bones
a) A True B True
b) A wrong B wrong
c) A True B does not explain the functions of A
d) A True B Wrong
Answer:
c) A True B does not explain the functions of A

Question 55.
Assertion A: The cranium belongs to immovably fixed joints.
Reason B: Structures of the flat skull bones are fibrous joints.
a) A True B Wrong
b) A True B explains the structure of A
c) A True B True
d) B does not explain the structure of A
Answer:
b) A True B explains the structure of A

Question 56.
Assertion A: The decreased synthesis of acetylcholine in the neuromuscular junction, causes myasthenia gravis.
Reason B: This leads to muscle fatigue weakness, paralysis.
a) A and B are True
b) A and B are wrong
c) A True B wrong
d) A wrong B True
Answer:
a) A and B are True

Question 57.
Match and arrange the sequence:


Answer:
a) I – D, II – C, III – A, IV – B

Question 58.
Match and arrange the sequence:


Answer:
b) I – C, II – D, III – B, IV -A

2 marks

II. Very Short answers

Question 1.
What is amoeboid movement?
Answer:
The movement of cells by streaming movements of the cytoplasm forming pseudo-podia is known as amoeboid movement, e.g., macrophages.

Question 2.
What are the types of muscles?
Answer:

• Skeletal muscle
• Visceral muscles
• Cardiac muscles

Question 3.
What is flagellar movement?
Answer:
The movement due to the lashing of flagella is known as flagellar movement, e.g., sperm cells.

Question 4.
Name the regulatory proteins in the thin filaments.
Answer:

• Tropomyosin
• Troponin

Question 5.
What is a fascicle?
Answer:
Each muscle is made up of bundles of muscle fibres called fascicles.

Question 6.
On the basis of ATP formation, how are muscles classified?
Answer:

• Oxidative fibres
• Glycolytic fibres

Question 7.
What is epimysium?
Answer:
The connective tissue covering the whole muscle is the epimysium.

Question 8.
What is perimysium?
Answer:
The connective tissue covering around each fascicle is the perimysium.

Question 9.
Differentiate the oxidative fibre from the glycolytic fibre.
Answer:

Oxidative fibre	Glycolytic fibre
1. Numerous mitochondria	There are few mitochondria
2. Depends on blood flow	Not depend on blood flow
3. Myoglobin is present	No myoglobin
4. These are known as red muscle fibres	These are called muscle fibres as white muscle fibres

Question 10.
What is endomysium?
Answer:
The connective tissue surrounding the muscle fibre is called the endomysium.

Question 11.
What is a tendon?
Answer:
Skeletal muscle is attached to the bone by a bundle of collagen fibres known as tendons.

Question 12.
What is an endoskeleton?
Answer:
It is found inside the body of vertebrates. It is composed of bones and cartilages, (eg) Man.

Question 13.
What is sarcoplasm?
Answer:
The cytoplasm of the muscle fibre is called the sarcoplasm.

Question 14.
What are Glycosomes?
Answer:
Glycosomes are the granules of stored glycogen that provide glucose during the period of muscle fiber activity.

Question 15.
What is sarcomere?
Answer:
The functional unit of the skeletal muscle is known as the sarcomere.

Question 16.
Name the ear ossicles?
Answer:

• Malleus
• incus
• stapes

Question 17.
What is meromyosin?
Answer:
The monomer of the myosin molecule is called meromyosin.

Question 18.
Name the openings of the skull?
Answer:

• The orbits
• Nasal cavity
• Foramen magnum

Question 19.
What is meant by foramen magnum?
Answer:

• It is a large opening found at the posterior base of the skull.
• Through this opening, the medulla oblongata of the brain descends down as the spinal cord.

Question 20.
What are oxidative fibres?
Answer:
The muscle fibres that contain numerous mitochondria and have a high capacity for oxidative phosphorylation are classified as oxidative fibres. They are also called red muscle fibres.

Question 21.
Name the first two bones of the vertebral column.
Answer:

1. Atlas
2. Axis

Question 22.
What are the functions of the vertebral column?
Answer:

• It protects the spinal cord.
• Supports the head
• Serves as the point of attachment for the ribs and musculature of the back.

Question 23.
Give short notes on sternum?
Answer:

• The sternum is a flat bone on the midventral line of j the thorax.
• It provides space for the attachment of the thoracic ribs and abdominal muscles.

Question 24.
What is a metaphysis?
Answer:
The bone region where the diaphysis and epiphyses meet is called the metaphysis.

Question 25.
What are true ribs?
Answer:
The first seven pairs of ribs are called true ribs. Daily they are attached to the thoracic vertebrae and ventrally connected to the sternum.

Question 26.
What is endosteum?
Answer:
Internal bone surfaces are covered with a delicate connective tissue membrane called the endosteum.

Question 27.
What is the sternum?
Answer:
The sternum is a flat bone on the midventral line of the thorax. It provides space for the attachment of the thoracic ribs and abdominal muscles.

Question 28.
What is meant by an appendicular skeleton?
Answer:
The bones of the upper and lower limbs along with their girdles constitute the appendicular skeleton. It is composed by 126 bones.

Question 29.
White the 3 segments of the lower limb.
Answer:

1. The thigh
2. the leg or the shank and
3. the foot.

Question 30.
What is meant by the acromion process?
Answer:
The scapula has a slightly elevated ridge called the spine which projects as a flat expanded process called the acromion.

Question 31.
What is meant by the glenoid cavity?
Answer:
Below the acromion is a depression called the glenoid cavity which articulates with the head of the humerus to form the shoulder joint.

Question 32.
What is meant by the olecranon process?
Answer:
The radius and ultra bones present in the forearm that form the pointed portion of the elbow called the olecranon process.

Question 33.
What is meant by carpal tunnel?
Answer:

• There are 8 bones in the wrist arranged in two rows of four each.
• The anterior surface of the wrist has a tunnel-like appearance. This tunnel is termed a carpal tunnel.

Question 34.
Name the bones which form the coxal bones.
Answer:

• Ilium
• Ischium
• Pubis

Question 35.
What is meant by pubic symphysis?
Answer:
Ventrally the two halves of the pelvic girdle meet and form the pubic symphysis containing fibrous cartilage.

Question 36.
Where calcium ion binds with the muscle fibre? Name the molecules which bind with calcium?
Answer:

• The calcium released from the sarcoplasm binds with the thin fibre of the muscle.
• The released calcium binds to troponin thin filaments.

III. Fill Up The Blanks With Suitable Options

1. Scapula – Acromian process
……………. – Bones of the upper arm
2. First 7 pair of rib bones – True ribs
11 and 12th pair of ribs – …………….
3. Cervical vertebrae – 7
……………. – Lumbar bones
4. Skull bones – 22
……………. – Skull bones
5. Thick fibres – Myosin
……………. – Thin fibres
6. Amoeboid movement – Macrophage cells
……………. – Sperm cells
Answer:

1. Olecranon process
2. Floating ribs
3. 5
4. 8
5. Actin
6. Flagellated movement

3 marks

IV. Short answers

Question 1.
Give short notes on skeletal muscle and their covering membranes.
Answer:

• Each muscle is made up of bundles of muscle fibres called fascicles. Each muscle fibre contains rod-like structures called myofibrils.
• The connective tissue covering the muscle is the epimysium.
• The covering around each fascicle is the perimysium.
• The muscle fibre is surrounded by endomysium.

Question 2.
Give the structure of a skeletel muscle fibre.
Answer:

• Each muscle fibre is thin and elongated.
• Most of the taper at one or both ends.
• Muscle fibres are surrounded by sarcolemma the cytoplasm of the muscle fibre is called the sarcoplasm.
• It contains glycosomes myoglobin and sarcoplasmic reticulum.
• Myoglobin is a red-coloured respiratory pigment and glycosomes are reserved glycogen.
• Muscle fibres contain muscle protein actin and myosin.

Question 3.
Give notes on slow oxidative fibres.
Answer:

• These fibers have low rates of myosin ATP hydrolysis but have the ability to make large amounts of ATP.
• This type of fiber seen in long-distance swimmers and long-distance runners.

Question 4.
Give notes on fast – oxidative fibres.
Answer:

• These fibres have high myosin ATP as activity and can make large amounts of ATP.
• They are suited for rapid action.

Question 5.
Give notes on fast glycolytic fibres.
Answer:

• These fibres have myosin ATP ase activity but cannot make as much ATP as oxidative fibres because their source of ATP in glycolysis.
• These fibres are best suited for rapid intense actions such as short sprints at maximum speed.

Question 6.
Name the facial bones.
Answer:
There are 14 facial bones.

1. Pair of maxilla
2. Pair of Zygomatic
3. Pair of Palantine
4. Pair of lacrimal
5.  Pair of Nasal
6. Mandible or lower jaw
7. Vomer

Question 7.
Give notes on fibrous joints.
Answer:

• They are immovably fixed joints in which no movement between the bones is possible.
• Sutures of the flat skull bones are fibrous joints.

Question 8.
Give notes on cartilaginous joints.
Answer:
They are slightly movable joints in which the joint surface is separated by cartilage and slight movement is only possible.

Question 9.
Give notes on synovial joints.
Answer:
They are freely movable joints the articulating bones are separated by a cavity which is filled with synovial fluid.

Question 10.
Give notes on myasthenia gravis.
Answer:

• It is an autoimmune disorder affecting the action of acetylcholine at the neuromuscular junction leading to fatigue.
• Weakening and paralysis of skeletal muscles.
• Acetylcholine receptors on the sarcolemma are blocked by antibodies leading to weakness of muscles.
• When the disease progresses it can make chewing swallowing talking and even breathing difficult.

Question 11.
Give notes on muscle fatigue.
Answer:

• It is the inability of a muscle to contract after repeated muscle contraction.
• This is due to lack of ATP and accumulation of lactic acid by anaerobic break down of glucose.

Question 12.
Give notes on the Atrophy of muscles.
Answer:

• A decrease in the activity of muscles results in the atrophy of muscles.
• There is a reduction in the size of the muscle and makes the muscle become weak which occurs with lack of usage as in chronic bedridden patients.

Question 13.
What is meant by muscle pull?
Answer:

• Muscle pull is actually a muscle tear.
  Atraumatic pulling of the fibres produces a tear known as a sprain.
• This can occur due to the sudden stretching of muscle beyond the point of elasticity.
• Back pain is a common problem caused by muscle pull due to improper posture with static sitting for long hours.

Question 14.
What is meant by muscular dystrophy?
Answer:

• The group of diseases collectively called muscular dystrophy is associated with the progressive degeneration of skeletel muscle fibers weakening the muscles and leading to death from lung or heart failure.
• (eg) Duchene muscular dystrophy.

Question 15.
What is meant by skeletel muscle glycogen analysis?
Answer:

• This is used to measure an athlete’s muscle glycogen.
• Muscle glycogen provides the main source of energy during anaerobic exercise.
• A single glycogen molecule may contain 5000 glucose molecules.

Question 16.
Give notes on osteoporosis?
Answer:

• It occurs due to deficiency of vitamin D and hormonal imbalance.
• It causes rickets in children and osteomalacia in adult females.
• The bones become soft and fragile.
• It can be minimized with adequate calcium intake vitamin D intake and regular physical activities.

Question 17.
What is carpal tunnel syndrome?
Answer:

• The narrow passage bounded by bones and ligaments in the wrist gets narrowed and pinches the median nerve.
• This syndrome is mostly seen among clerks, software professionals, and people who constantly play or text on mobile phones.

5 Marks

V. Give Detailed Answers 

Question 1.
Explain the structure of skeletal muscle fibre?
Answer:

1. Each muscle fibre is thin and elongated.
2. It has multiple oval nuclei beneath sarcolemma.
3. The cytoplasm of the muscle fibre is called sarcoplasm.
4. It contains glycosomes, the stored glycogen granules, myoglobin, respiratory pigment, and sarcoplasmic reticulum.
5. Actin and myosin are muscle proteins present in the muscle fibre.
6. Each myofibril has a repeated series of dark and light bands called A-bands and I-bands.
7. Each dark band has a lighter region in its middle called the H-zone.
8. Each H-zone is bisected vertically by a dark line called the M-line.
9. Each light I-band has a darker mid-line area called the Z-disc.
10. The sarcomere is the functional unit of the skeletal muscle. It is a region of a myofibril between two successive Z-discs.
11. Sarcomere has thick and thin filaments. The thick filaments extend the entire length of the A-band, the thin filaments extend across the I-band and partly into the A-band.
12. The invagination of the sarcolemma forms transverse tubules (T-tubules) and they penetrate into the junction between the A and I-bands.

Question 2.
Describe the structure of the sarcomere.
Answer:

• The unit of the skeletal muscle is the sarcomere A sarcomere is the region of a myofibril between two successive z – discs.
• It contains an ‘A’ band with a half I band which are perfectly aligned with one another.
• This type of arrangement gives the cell a striated appearance.
• Each dark band has a lighter region in its middle called the M – zone.
• Each H – zone is bisected vertically by a dark line called the M – line.
• The I bands have a darker mid-line area called the z – disc.

• Inside the sarcomere, two types of filaments are present namely the thick filaments and thin filaments.
• The thick filaments extend the entire length of the A band, the thin filaments extend across the I band and partly into the A – band.
• The invagination of the sarcolemma forms transverse (T- tubules) tubules and they penetrate into the junction between the A and I bands.

Question 3.
Describe the structure of muscle protein.
Answer:
Contraction of the muscle depends on the presence of contractile proteins such as actin and myosin.
Myosin fibre:

• The thick filaments are composed of the protein myosin.
• Each myosin molecule is made up of a monomer called meromyosin.
• The meromyosin have a globular head with a j short arm and a tail.
• The short arm have heavy meromyosin and the tail portion have light meromyosin.
• The head bears actin-binding site and an ATP binding site
• It also contains ATP ase enzyme that split ATP to generate energy for the contraction of muscle.

Actin filament:

• Actin has polypeptide subunits called globular actin or G – actin and filamentous form F – actin.
• Each thin filament is made of two F – actins helically wound to each other.
• Each F – actin is a polymer of monomeric G – actins, It also contains a binding site for myosin.
• The thin filament contain several regulatory protein like tropomyosin, troponin, which help in regulating the contraction of muscles along with actin and myosin.

Thick filament:
Each thick filament consists of many myosin molecules whose heads produce at opposite ends of the filament Portion of a thick filament

Thin filament:
A thin filament consists of two strands of actin subunits twisted into a helix plus two types of regulatory proteins (troponin and tropomyosin) Portion of a thin filament.

Question 4.
Give the schematic representation of muscle contraction.
Answer:

Question 5.
Write the functions of skeletal system?
Answer:
Functions of skeletal system

1. Support -It forms a rigid framework and supports the weight of the body against gravity.
2. Shape – It provides and maintains the shape of the body.
3. Protection – It protects the delicate internal organs of the body.
4. Acts as reservoir – It stores minerals such as calcium and phosphate. Fat (triglyceride) is stored in yellow bone marrow and represents a source of stored energy for the body.
5. Locomotion – It acts as lever along with the muscles attached to it.
6. Strength – It can withstand heavyweight and absorbs mechanical shock.
7. Asa hemopoietic tissue – Red and white blood cells are produced in the bone marrow of the ribs, spongy bones of vertebrae and extremities of long bones.

Question 6.
Explain the bones that form the skull?
Answer:
The skull is composed of two sets of bones – cranial and facial bones. It consists of 22 bones of which 8 are cranial bones and 14 are facial, bones. The cranial bones form the hard protective outer covering of the brain and called the brain box. The capacity of the cranium is 1500 cm3.

These bones are joined by sutures which are immovable. They are paired parietal, paired temporal and individual bones such as the frontal, sphenoid, occipital and ethmoid. The large hole in the temporal bone is the external auditory meatus. In the facial bones maxilla, zygomatic, palatine, lacrimal, nasal are paired bones whereas mandible or lower jaw and vomer are unpaired bones. They form the front part of the skull.

A single U-shaped hyoid bone is present at the base of the buccal cavity. It is the only bone without any joint. Each middle ear contains three tiny bones- malleus, incus, and stapes collectively are called ear ossicles. The upper jaw is formed of the maxilla and the lower jaw is formed of the mandible.

The upper jaw is fused with the cranium and is immovable. The lower jaw is connected to the cranium by muscles and is movable. The most prominent openings in the skull are the orbits and the nasal cavity. The foramen magnum is a large opening found at the posterior base of the skull. Through this opening, the medulla oblongata of the brain descends down as the spinal cord.

Question 7.
Write a short note on the vertebral column?
Answer:
The vertebral column is also called the backbone. It consists of 33 serially arranged vertebrae which are interconnected by cartilage known as an intervertebral disc. The vertebral column extends from the base of the skull to the pelvis and forms the main framework of the trunk. The vertebral column has five major regions.

They are the cervical, thoracic, lumbar, sacrum (5 sacral vertebrae found in the infant which are fused to form one bone in the adult), and coccyx (4 coccygeal vertebrae found in the infant which are fused to form one bone in the adult).

Each vertebra has a central hollow portion, the neural canal, through which the spinal cord passes. The first vertebra is called the atlas and the second vertebra is called the axis. Atlas is articulated with the occipital condyles. The vertebral column protects the spinal cord, supports the head, and serves as the point of attachment for the ribs and musculature of the back.

Question 8.
Give an account of the ribcage.
Answer:

• There are 12 pairs of ribs.
• Each rib bone is connected dorsally to the vertebral column and ventrally to the sternum.
• It has two articulation surfaces on its dorsal end called bicephalic.
• The first 7 pairs of ribs are called true ribsorvertebro – sternal ribs.
• Dorsally they are attached to the thoracic vertebrae and ventrally connected to the sternum with the help of hyaline cartilages.
• The 8th, 9th, and 10th pairs of ribs do not articulate directly with the sternum but joined with the cartilaginous part of the seventh rib.
• These are called false ribs or vertebro – chondral ribs.
• The last 11th and 12th pairs of ribs are not connected ventrally.

• They are called floating ribs or vertebral ribs.
• Thoracic vertebrae ribs and sternum from the rib cage.

Question 9.
Give an account of the pectoral girdle?
Answer:

• The upper limbs are attached to the pectoral girdles.
• These are very light and allow the upper limbs a degree of mobility not seen anywhere else in the body.
• The girdle is formed of two halves.
• Each pectoral girdle consists of a clavicle or collar bone and a scapula.
• The scapula is a large triangular bone situated in the dorsal surface of the ribcage between the second and seventh ribs.
• It has an elevated expanded process called the acromion.

• The clavicle articulates this process.
• Below the acromion is a depression called the glenoid cavity which articulates with the head of the humerus to form the shoulder joint.
• Each clavicle is a long slender bone with two curvatures which lie horizontally and connect the axial skeleton with the appendicular skeleton.

Question 10.
Describe the structure of the upper limb.
Answer:

• The upper limb consists of 30 separate bones and is specialized for mobility.
• The region between the shoulder and elbow is the humerus.
• The head of humerus articulates with the glenoid cavity of the scapula and forms the shoulder joint.
• The distel end of humerus articulates with the two forearm bones the radius and ulna
• Olecranon process is situated at the upper end of the ulna which forms the pointed portion of the elbow.
• The hand consists of carpals metacarpals and phalanges.
• Carpals the wrist bones 8 in number are arranged in two rows of four each and form a tunnel termed as carpal tunnel.
• Meta carpals the palm bones are 5 in number and phalanges the digit bones are 14 in number.

Question 11.
Give an account of pelvic girdle.
Answer:

• The pelvic girdle is a heavy structure specialised for weight-bearing.
• It is composed of two hib bones called coxal bones that secure the lower limbs to the axial skeleton.
• Together with the sacrum and coccyx the hib bones form the basin-like bony pelvis.
• Each coxal bone consists of three fused bones ilium, ischium, and pubis.
• At the point of fusion of these three bones forms a deep hemispherical socket called the acetabulum present on the lateral surface of the pelvis.
• It receives the head of the femur at hip joint and helps in the articulation of the femur.
• Ventrally the two halves of the pelvic girdle meet and form the pubic symphysis containing fibrous cartilage.
• The ilium is the superior flaring portion of the hip bone. Each ilium forms a secure joint with the sacrum posteriorly.
• The ischium is a curved bar of bone. The ‘V’ shaped pubic bones articulate anteriorly at the pubic symphysis.
• The pelvis of male is deep and narrow with larger heavier bones and the female is shallow wide and flexible in nature and this helps during pregnancy which is influenced by female hormones.

Question 12.
Give an account of the lower limb.
Answer:

• The lower limb consists of 30 bones which carries the entire weight of the erect body and is subjected to exceptional forces when we jump or run.
• The bones of the lower limbs are thicker and stronger than the upper limbs.
• Each lower limb consists of the thigh, the leg or the shank and the foot.
• The femur is the strongest and longest bone of the body.
• The head of femur articulates with the acetabulum of the pelvis to form the hip joint.
• The tibia and fibula form the skeleton of the shank.
• A thick triangular patella forms the knee cap which protects the knee joint arteriorly and improves the leverages of thigh muscles acting across the knee.
• The foot includes the bones of ankle the tarsus (7) the metatarsus (5) and the phalanges or toe ebones. (14)
• The foot supports our body weight and acts as a lever to propel the body forward while walking and running.
• The phalanges of the foot are smaller than those of the fingers.

Question 13.
Give an account of a structure of a typical long bone.
Answer:

• The typical long bone has a diaphysis, epiphysis, and membranes.
• A tubular diaphysis or shaft forms the long axis of the bone and has a central medullary cavity.
• The epiphyses are the bone ends.
• Compact bone forms the exterior of epiphyses and their interior contains spongy bone with red marrow.
• The region where the diaphysis and epiphysis meet is called metaphysics.
• The external surface of the entire bone except the joint surface is covered by a double-layered membrane called the periosteum.
• The outer fibrous layer is dense irregular connective tissue.
• The inner osteogenic layer consists of osteoblasts cell. ( bone-forming cells) and osteoclasts cells (E bone – destroying cells)
• There are primitive stem cells osteogenic cells that give rise to the osteoblasts.
• The periosteum is richly supplied with nerve fibres lymphatic vessels and blood vessels.
• Internal bone surfaces are covered with a delicate connective tissue membrane called the endosteum It also contains osteoblasts and osteoclasts cells.
• Between the epiphysis and diaphysis growth plate or epiphyseal plate is present.

Question 14.
Explain the disorders of the skeletal system?
Answer:
Arthritis and osteoporosis are the major disorders of the skeletal system.
1. Arthritis: Arthritis is an inflammatory or degenerative disease that damages the joints. There are several types of arthritis.

(I) Osteoarthritis: The bone ends of the knees and other freely movable joints wear away as a person ages. The joints of the knees, hip, fingers, and vertebral column are affected.

(II) Rheumatoid arthritis: The synovial membranes become inflamed and there is an accumulation of fluid in the joints. The joints swell and become extremely painful. It can begin at any age but symptoms usually emerge before the age of fifty.

(III) Gouty arthritis or gout: Inflammation of joints due to accumulation of uric acid crystals or inability to excrete it. It gets deposited in synovial joints.

2. Osteoporosis: It occurs due to deficiency of vitamin D and hormonal imbalance. The bone becomes soft and fragile. It causes rickets in children and osteomalacia in adult females. It can be minimized with adequate calcium intake, vitamin D intake, and regular physical. activities.

Question 15.
Tabulate the differentiate between joints man
Answer:

Pivot joint	between atlas and axis
Gliding joint	between the carpals
Saddle joint	between the carpal and metacarpal
Ball and socket joint	between humerus and pectoral gridle
Hinge joint	Knee joint
Condyloid or Angular or Ellipsoid	Joint between radius joint and carpal

Question 16.
Draw the diagram of different types of fracture and arrange them.
Answer:

Question 17.
Bones of the skeletal system. Table: 1 Bones of skeletal system
Answer:

Notes:

1. The strongest muscle in the human: Massetter in cheeks
2. The smallest muscle in the human: Middle ear in stapedius
3. Well moving muscle: Tongue
4. The largest muscle in the human: Buttock in Glutens Maximus
5. The longest muscle in the human : Hip to knee (sartorius)
6. Total number of bones is adults = 206

Question 18.
Explain the basic categories of exercise and physical activity?
Answer:
Exercise and physical activity fall into four basic categories. Endurance, strength, balance, and flexibility. Endurance or aerobic activities increase the breathing and heart rate. They keep the circulatory system healthy and improve overall fitness.

Strength exercises make the muscles stronger. They help to stay independent and cany out everyday activities such as climbing stairs and carrying bags.

Balance exercises help to prevent falls which is a common problem in older adults. Many strengthening exercises also improve balance.

Flexibility exercises help to stretch body muscles for more freedom of joint movements.