Locomotion and Movement MCQs [Difficult level:Easy][From NCERT]

Question: From NCERT | NEET || [Difficult level:Easy] |||

.The human skull has 22 bones with ..................cranial bones and ............................ facial bones

1. 10,12

2. 14,8

3. 12,10

4. 8,14

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Answer ▽ ✅Verified

4. 8,14

SKELETAL SYSTEM

Skeletal system consists of a framework of bones and a few cartilages.
This system has a significant role in movement shown by the body.
Imagine chewing food without jaw bones and walking around without
the limb bones. Bone and cartilage are specialised connective tissues.
The former has a very hard matrix due to calcium salts in it and the latter
has slightly pliable matrix due to chondroitin salts. In human beings,
this system is made up of 206 bones and a few cartilages. It is grouped
into two principal divisions – the axial and the appendicular skeleton.
Axial skeleton comprises 80 bones distributed along the main axis
of the body. The skull, vertebral column, sternum and ribs constitute
axial skeleton. The skull is composed of two sets of bones –

cranial and facial, that totals to 22 bones. Cranial bones are 8 in number.

They form the hard protective outer covering, cranium for the brain. The

facial region is made up of 14 skeletal elements which form the front part

of the skull. A single U-shaped bone called hyoid is present at the base of

the buccal cavity and it is also included in the skull. Each middle ear

contains three tiny bones – Malleus, Incus and Stapes, collectively called

Ear Ossicles. The skull region articulates with the superior region of the

vertebral column with the help of two occipital

condyles (dicondylic skull).

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Question: From NCERT | NEET || [Difficult level:Easy] |||

.Which of the following has ATPase activity?

1. Actin 2. Tropomyosin

3. Head of myosin 4. Troponin

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Answer ▽ ✅Verified

3. Head of myosin

Structure of Contractile Proteins

Each actin (thin) filament is made of two ‘F’ (filamentous) actins

helically wound to each other. Each ‘F’ actin is a polymer of monomeric

‘G’ (Globular) actins. Two filaments of another protein, tropomyosin

also run close to the ‘F’ actins throughout its length. A complex protein

Troponin is distributed at regular intervals on the tropomyosin. In the

resting state a subunit of troponin masks the active binding sites for

myosin on the actin filaments.

Each myosin (thick) filament is also a polymerised protein. Many

monomeric proteins called Meromyosins constitute one

thick filament. Each meromyosin has two important parts, a globular

head with a short arm and a tail, the former being called the heavy

meromyosin (HMM) and the latter, the light meromyosin (LMM). The HMM

component, i.e.; the head and short arm projects outwards at regular

distance and angle from each other from the surface of a polymerised myosin

filament and is known as cross arm. The globular head is an active ATPase

enzyme and has binding sites for ATP and active sites for actin.

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Question: From NCERT | NEET || [Difficult level:Easy] |||

.The ATPase activity of the myosin head is dependent on:

1. Magnesium ions

2. Manganese ions

3. Calcium ions

4. Ferric ions

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Answer ▽ ✅Verified

3. Calcium ions

Muscle contraction is initiated by a signal sent by the central nervous
system (CNS) via a motor neuron. A motor neuron alongwith the muscle
fibres connected to it constitute a motor unit. The junction between a
motor neuron and the sarcolemma of the muscle fibre is called the
neuromuscular junction or motor-end plate. A neural signal reaching
this junction releases a neurotransmitter (Acetyl choline) which generates
an action potential in the sarcolemma. This spreads through the muscle
fibre and causes the release of calcium ions into the sarcoplasm. Increase
in Ca++ level leads to the binding of calcium with a subunit of troponin on
actin filaments and thereby remove the masking of active sites for myosin.
Utilising the energy from ATP hydrolysis, the myosin head now binds to
the exposed active sites on actin to form a cross bridge

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Question: From NCERT | NEET || [Difficult level:Easy] |||

.During muscle contraction, the length of all the following gets reduced except:

1. H-Zone

2. A-Band

3. I-Band

4. Sacromere

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Answer ▽ ✅Verified

2. A-Band

the exposed active sites on actin to form a cross bridge. This pulls the attached actin filaments towards the centre of ‘A’ band. The
‘Z’ line attached to these actins are also pulled inwards thereby causing a
shortening of the sarcomere, i.e., contraction. It is clear from the above
steps, that during shortening of the muscle, i.e., contraction, the ‘I’ bands
get reduced, whereas the ‘A’ bands retain the length.

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Question: From NCERT | NEET || [Difficult level:Easy] |||

.What is true about the white muscle fibers?

1. Myoglobin content is high

2. They have a large number of mitochondria

3. They depend on anaerobic process for energy

4. They are adapted for slow sustained activities

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Answer ▽ ✅Verified

3. They depend on anaerobic process for energy

Muscle contains a red coloured oxygen storing

pigment called myoglobin. Myoglobin content is high in some of the

muscles which gives a reddish appearance. Such muscles are called the

Red fibres. These muscles also contain plenty of mitochondria which can

utilise the large amount of oxygen stored in them for ATP production.

These muscles, therefore, can also be called aerobic muscles. On the

other hand, some of the muscles possess very less quantity of myoglobin

and therefore, appear pale or whitish. These are the White fibres. Number

of mitochondria are also few in them, but the amount of sarcoplasmic

reticulum is high. They depend on anaerobic process for energy.

Why do white muscle fibres have more sarcoplasmic reticulum?

White muscle fibres are designed for quick movements (like the muscles in your hands & for moving your eyes). Also they are used for high energy activity for short periods of time. Due to this they need more sarcoplasmic reticulum so that they are better equipped for quick release and re-uptake of calcium ions.

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Question: From NCERT | NEET || [Difficult level:Easy] |||

.Scapula is a large triangular flat bone situated in the dorsal part of the thorax between:

1. the second and fifth ribs

2. the second and seventh ribs

3. the third and sixth ribs

4. the third and eighth ribs

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Answer ▽ ✅Verified

2. the second and seventh ribs

Pectoral and Pelvic girdle bones help in
the articulation of the upper and the lower limbs
respectively with the axial skeleton. Each

girdle is formed of two halves.Each half of

pectoral girdle consists of a clavicle and a
scapula . Scapula is a large
triangular flat bone situated in the dorsal part
of the thorax between the second and the
seventh ribs. The dorsal, flat, triangular body
of scapula has a slightly elevated ridge called
the spine which projects as a flat, expanded
process called the acromion. The clavicle
articulates with this. 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. This bone
is commonly called the collar bone.

Pelvic girdle consists of two coxal bones
. Each coxal bone is formed by
the fusion of three bones – ilium, ischium and
pubis. At the point of fusion of the above bones
is a cavity called acetabulum to which the thigh
bone articulates. The two halves of the pelvic
girdle meet ventrally to form the pubic
symphysis containing fibrous cartilage.

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Question: From NCERT | NEET || [Difficult level:Easy] |||

.Match each item in Column I with one item in Column II and chose your answer from the codes given below:

Column I

Column II

I. Acetabulum

II. Glenoid Cavity

III. Vertebrosternal ribs

IV. Vertebrochondral ribs

1. Pectoral girdie

2. Pelvic girdie

3. 7 pairs

4. 3 pairs

Codes

I II III IV

(1) 1 2 3 4

(2) 2 1 4 3

(3) 2 1 3 4

(4) 1 2 4 3

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Answer ▽ ✅Verified

(3) 2 1 3 4

Pectoral and Pelvic girdle bones help in
the articulation of the upper and the lower limbs
respectively with the axial skeleton. Each

girdle is formed of two halves.Each half of

There are 12 pairs of ribs. Each rib is a

thin flat bone connected dorsally to the

vertebral column and ventrally to the sternum.

It has two articulation surfaces on its dorsal

end and is hence called bicephalic. First seven

pairs of ribs are called true ribs. Dorsally, they

are attached to the thoracic vertebrae and

ventrally connected to the sternum with the

help of hyaline cartilage. The 8th, 9th and 10th

pairs of ribs do not articulate directly with the

sternum but join the seventh rib with the help

of hyaline cartilage. These are called

vertebrochondral (false) ribs. Last 2 pairs (11th

and 12th) of ribs are not connected ventrally

and are therefore, called floating ribs. Thoracic

vertebrae, ribs and sternum together form the

rib cage .

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Question: From NCERT | NEET 2017 || [Difficult level:Easy] |||

.The pivot joint between atlas and axis is a type of

(1) fibrous joint

(2) cartilaginous joint

(3) synovial joint

(4) saddle joint

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Answer ▽ ✅Verified

(3) synovial joint

JOINTS

Joints are essential for all types of movements
involving the bony parts of the body.

Locomotory movements are no exception to

this. Joints are points of contact between bones, or between bones and

cartilages. Force generated by the muscles is used to carry out movement

through joints, where the joint acts as a fulcrum. The movability at these

joints vary depending on different factors. Joints have been classified into

three major structural forms, namely, fibrous, cartilaginous and synovial.

Fibrous joints do not allow any movement. This type of joint is shown

by the flat skull bones which fuse end-to-end with the help of dense fibrous

connective tissues in the form of sutures, to form the cranium.

In cartilaginous joints, the bones involved are joined together with

the help of cartilages. The joint between the adjacent vertebrae in the

vertebral column is of this pattern and it permits limited movements.

Synovial joints are characterised by the presence of a fluid filled synovial

cavity between the articulating surfaces of the two bones. Such an arragement

allows considerable movement. These joints help in locomotion and many

other movements. Ball and socket joint (between humerus and pectoral

girdle), hinge joint (knee joint), pivot joint (between atlas and axis), gliding

joint (between the carpals) and saddle joint (between carpal and metacarpal

of thumb) are some examples.

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Question: From NCERT | NEET || [Difficult level:Easy] |||

.Select the correct matching of the type of the joint with the example in human skeletal

system

Types of joint Example

1. Cartilaginous joint Between frontal and parietal

2. Pivot joint Between third and fourth Cervical vertebrae

3. Hinge joint Between humerus and pectoral girdle

4. Gliding joint Between carpals