Locomotion and Movement Class 11 Biology Exam Questions

Please refer to Locomotion and Movement Class 11 Biology Exam Questions provided below. These questions and answers for Class 11 Biology have been designed based on the past trend of questions and important topics in your class 11 Biology books. You should go through all Class 11 Biology Important Questions provided by our teachers which will help you to get more marks in upcoming exams.

Class 11 Biology Exam Questions Locomotion and Movement

Class 11 Biology students should read and understand the important questions and answers provided below for Locomotion and Movement which will help them to understand all important and difficult topics.

Objective Type Questions

Question. Hyoid/tongue bone is
(a) T-shaped
(b) J-shaped
(c) U-shaped
(d) L-shaped

Question. Which of the following is not included under ear ossicles?
(a) Malleus
(b) lleum
(c) Incus
(d) Stapes

Question. Human skull is
(a) Dicondylic
(b) Monocondylic
(c) Procoelous
(d) Haterocoelous

Question. Which of the following vertebra in adult human are fused ones?
(a) Thoracic and lumber
(b) Thoracic and cervical
(c) Sacral and coccygeal
(d) Cervical and coccygeal

Question. Which of the following is not correct about sternum?
(a) It is commonly called breast bone
(b) It is a flat bone
(c) It is 2 in number
(d) It is located on the ventral midline of thorax

Question. Typical ribs are
(a) Monocephalic
(b) Dicephalic
(c) Tricephalic
(d) Tetracephalic

Question. Pick up the correct match

Column – I	Column – II
A. False ribs	I. 1st to 7th pair
B. True ribs	II. 11th and 12th pair
C. Floating ribs	III. 8th pair to 10th pair
D. Sternum	IV. One

Options :
(a) A – I, B – II, C – III, D – IV
(b) A – IV, B – III, C – II, D – I
(c) A – I, B – III, C – II, D – IV
(d) A – III, B – I, C – II, D – IV

Question. Ribcage is formed by all except
(a) Thoracic vertebrae
(b) Lumbar vertebrae
(c) Ribs
(d) Sternum

Question. Number of bones in human appendicular skeleton is
(a) 80
(b) 120
(c) 126
(d) 206

Question. Phalangeal/ digital formula for human hand/foot is
(a) 0,2,2,3
(b) 0,2,3,3,3
(c) 2,2,3,3,3
(d) 2,3,3,3,3

Question. Which of the following statement is false?
(a) Each myosin is polymerised protein
(b) Many meromysin constitute one thick filament (myosin)
(c) Each meromysin’s tail is called heavy meromyosin (HMM) and head is called light meromyosin (LMM)
(d) The globular head has an active ATPase enzyme and has binding sites for ATP and active sites for actin

Question. ATP provides energy for muscle contraction by allowing
(a) An action potential formation is the muscle cell
(b) Cross bridge detachment of myosin from actin
(c) Cross-bridge attachment of myosin to actin
(d) Release Ca⁺² from sarcoplasmic reticulum

Question. Motor end plate is a
(a) Neuromuscular junction
(b) Plate of motor neuron
(c) Dendron of motor neuron
(d) Gradient of proton motive force

Question. The energy for muscle contraction is most directly caused by
(a) Phosphocreatin
(b) ATP
(c) Anaerobic respiration
(d) Aerobic respiration

Question. Put the following phrases in proper order to describe what occurs at the neuromuscular junction to trigger muscle contraction
A. Receptor sites on sarcolemma
B. Nerve impulse
C. Release of calcium ions from sarcoplasmic reticulum
D. The neurotransmitter acetylcholine is released
E. Sarcomere shortens
F. Synaptic cleft
G. Spread of impulses over sarcolemma on T-tubules
Options :
(a) B,D,A,F,G,C,E
(b) B,D,F,A,G,C,V
(c) A,B,C,D,E,F,G
(d) G,F,E,D,C,B,A

Question. The muscle band that remains unchanged during muscle contraction and relaxation of skeletal muscle is
(a) I
(b) A
(c) H
(d) Z-line

Question. The compound or pigment acting as an oxygen store in skeletal muscle is
(a) Myoglobin
(b) Haemoglobin
(c) Myokinase of ATP
(d) Cytochrome

Question. Skeletal system consists of
(a) Only bones
(b) Only cartilage
(c) A framework of bone and few cartilage
(d) A frame work of cartilage and a few bones

Question. Cartilage has slightly pliable matrix due to
(a) Chondroitin salts
(b) Osteoblast
(c) Chondroclasts
(d) Osteoclast

Question. Number of bones make up the human skeleton?
(a) 80
(b) 106
(c) 206
(d) None

Very Short Answer Type Questions:

Question. Sarcolemma, sarcoplasm and sarcoplasmic reticulum refer to particular type of cell in our body. Which is this cell and to what parts of that cell do these names refer to?
Ans. There parts belongs to the muscle fibre, which is lined by the plasma membrane called sarcolemma. Muscle fibre is a syncitium because sarcoplasm (the cytoplasm) of muscle fibre contains number of nuclei and sarcoplasmic reticulum is the endoplasmic reticulum of the muscle fibre and is the store house of calcium ions.

Question. Give the location of a ball and socket joint in a human body
Ans. Ball and socket joint are present between humerus and pectoral girdle. These joints allows free movement of bone in all direction. e.g., shoulder jointds (humerus bone in socket of pectoral girdle) and hip joints femur bone in socket pelvic girdle.

Question. Locomotion requires a perfect coordinated activity of muscular ………systems.
Ans. Locomotion requires a prefect coordinated activity of muscular, skeletal and neural systems.

Question. How do our bone joints function without grinding noise and pain?
Ans. The presence of synovial fluid, between articulating surface of the two bones enclosed within synovial cavity of synovial joints to makes our joints to function without grinding noise and pain.

Question. The three tiny bones present in middle ear are called ear ossicles. Write them in correct sequence beginning from ear drum.
Ans. Each middle ear contains three tiny bones, named, i.e., malleus, incus and stapes which are collectively called as ear ossicles.

Question. Which tissue is afflicted by myasthenia gravis? What is the underlying cause.
Ans. Myasthenia gravis is an autoimmune disorder of skeletal muscle, affecting neuromuscular junction, that leads to fatigue, weakening and paralysis of the skeletal muscle.

Question. Name the cells/tissues in human body which
(a) exhibit amoeboid movement (b) exhibit ciliary movement
Ans. (a) Macrophages and leucocytes in blood exhibit amoeboid movement. Cytoskeletal elements like microfilaments are also involved in amoeboid movement.
(b) Ciliary Movement These types of movements occurs mostly in the internal organs, which are lined by the ciliated epithelium. e.g., cilia in trachea helps in removing dust particle and foreign substances inhaled along with atmospheric air.
Passage of ova through the female reproductive tract is also facilitated by the ciliary movement. This is due to the presence of ciliated epithelium in the Fallopian tube.

Question. Our forearm is made of three different bones. Comment.
Ans. Our forearm is made of three different bones, i.e., humerus, radius and ulna.These bones can be seen in following figure

Question. Label the different components of actin filament in the diagram given below

Ans. Representing different component of actin filament

Question. What is the difference between the matrix of bones and cartilage?
Ans. Difference between the matrix of bones and cartilage

Short Answer Type Questions:

Question. Exchange of calcium between bone and extracellular fluid takes place under the influence of certain hormones
(a) What will happen if more of Ca²⁺ is in extracellular fluid?
(b) What will happen if very less amount of Ca²⁺ is in the extracellular fluid?
Ans. (a) More Ca²⁺ concentration in extracellular fluid is associated with hyperparathyroidism.
It causes demineralisation, resulting in softening and bending of the bones. This condition leads to osteoporosis.
(b) Very less amount of Ca²⁺ in extracellular fluid is associated with hypoparathyroidism.
This increases the excitability of nerves and muscles, causing cramps, sustained contraction of the muscles of larynx, face, hands and feet. This disorder is called parathyroidtetany or hypercalcemictetany.

Question. Write a few lines about gout.
Ans. Gout is a disease, caused due to defect in purine metabolism. It causes accumulation of excess of uric acid and its crystals in the joints. The level of uric acid and crystals of its salts get raised in blood causing their accumulation in the joints causes gouty arthritis.
The excess of urates in blood can also lead to the formation stones in the kidneys.

Question. Rahul exercises regularly by visiting a gymnasium. Of late he is gaining weight. What could be the reason? Choose the correct answer and elaborate.
(a) Rahul has gained weight due to accumulation of fats in body
(b) Rahul has gained weight due to increased muscle and less of fat
(c) Rahul has gained weight because his muscle shape has improved
(d) Rahul has gained weight because he is accumulating water in the body
Ans. (b) Rahul has gained weight because his muscle shape has changed. Regular exercise increase the body muscle as there is an enlargement of muscles due to increase in the amount of sarcoplasm and mitochondria and the strength he to developed led him gain the mass and size of body muscle and reduction in fat content.

Question. What are the points for articulation of pelvic and pectoral girdles?
Ans. Pectoral girdle Each half of the pectoral girdle consist of a clavicle and a scapula. The dorsal flat, triangular body of scapula has a slightly elevated ridge called the spine that, projects a flat expanded process called the acromion and the clavicle articulating with it.
Below the acromion their is a depression called the glenoid cavity which articulates with the head of the humerous to form the shoulder joint. Pelvic girdle consist of two coxal bones.
each formed by the fusion of three bones, ilium, ischium and pubis. It articulates with femur through a cavity called acetabulum forming thigh joint.

Question. Name atleast two hormones which result in fluctuation of Ca²⁺ level.
Ans. Parathyroid hormone and calcitonin results in the fluctuation of Ca²⁺ level. Parathyroid Hormone (PTH) increases the Ca²⁺ levels in the blood. PTH acts on the bones and stimulates the process of bone resorption (dissolution/demineralisation).
PTH also stimulates reabsorption of Ca²⁺ by the renal tubules and increases Ca²⁺ absorption from the digested food.
Calcitonin is a 32-amino acid linear polypeptide hormone, that is produced in humans primarily by the parafollicular cells of the thyroid. It acts by reducing blood calcium (Ca²⁺), levels opposing the effect of Parathyroid Hormone (PTH).

Question. With respect to rib cage, explain the following
(a) bicephalic ribs (b) true ribs
(c) floating ribs
Ans. (a) Bicephalic ribs, each ribs has two articulating surfaces on its dorsal end hence, are called as bicephalic ribs.
(b) True ribs are the first seven pairs of ribs Dorsally these ribs are attached to the thoracic vertebrae and ventrally connected to the sternum with the help of hyaline cartilage.
(c) Floating ribs are the last two pair (11th and 12th) of ribs and are not connected ventrally to the sternum therefore, called as floating ribs.

Question. Radha was running on a treadmill at a great speed for 15 minutes continuously. She stopped the treadmill and abruptly came out. For the next few minutes, she was breathing heavily/fast. Answer the following questions.
(a) What happened to her muscles when she did strenuously exercised?
(b) How did her breathing rate change?
Ans. (a) Due, to continuous exercise her muscles got fatigues because of the accumulation of lactic acid within skeletal muscles. Pain is also oftenly experienced in the fatigued muscles.
(b) Her breathing rate changes from normal to high as during exercise, her body muscle require more oxygen for the ATP production, than the normal value, hence her breathing enhances, to lake most oxygen from the atmosphere.

Question. What is the source of energy for muscle contraction?
Ans. ATP (Adenosin Triphosphate) is the source of energy for muscle contraction. The head of each myosin molecule contains an enzyme called myosin ATPase.
In the presence of this enzyme along with Ca²⁺ then, and Mg²⁺ ions the ATP moleculebreaks down into ADP and inorganic phosphate, thus releasing energy in the head of myosin.

Energy from ATP causes energised myosin to cross bridges and to bind with actin and in this way initiates muscle contraction.

Question. In old age, people often suffer from stiff and inflamed joints. What is this condition called? What are the possible reasons for these symptoms?
Ans. The condition of stiff and inflammed joints is called as osteoporosis. It is an age-related disorder characterised by decreased bone mass and increased chances of fractures.
Decreased levels of estrogen is a common cause for osteoporosis in females after menopause, in old aged females.

Long Answer Type Questions:

Question. Explain sliding filament theory of muscle contraction with neat sketches.
Ans. Sliding filament theory
This theory is applicable to smooth, cardiac and skeletal muscles. The essential features of this theory are as follows
(i) During muscle contraction, thin myofilaments slide inward towards the H-zone.
(ii) The sarcomere, the basic unit of muscle contraction, shortens, without changing the length of thin and thick myofilaments.
(iii) The cross-bridge of the thick myofilaments connect with the portions of actin of the thin myofilaments. These cross-bridge move on the surface of the thin myofilaments, resulting in the sliding of thin and thick myofilaments over each other.
(iv) The length of the thick and thin myofilaments do not change during muscle contraction.
(v) A muscle fibre maintains a resting potential under resting conditions just like a nerve fibre. As soon as a nerve impulse reaches the terminal end of the axon, small sacs called synaptic vesicles fuse with the axon membrane and release a chemical transmitter,called acetylcholine.
It diffuses across the synaptic cleft (the space between the axon membrane and the motor end plate) and binds to the receptor sites of the motor end plate.
(vi) As soon as depolarisation of the motor end plate reaches a certain level, it creates an action potential. After this, an enzyme cholinesterase present along with the receptor sites for acetylcholine breaks down acetylcholine into acetate and choline.
A portion of the choline diffuses back to the axon and is reused to synthesise more acetylcholine for the transmission of subsequent impulses.
(vii) Calcium plays a key regulatory role in muscle contraction. The Ca⁺ ions bind to troponin causing a change in its shape and position. This in turn alters the shape and position of tropomyosin.
This shift exposes the active sites on the F-actin molecules and myosin cross-bridges are then able to bind to these active sites.
(viii) The head of each myosin molecule contains an enzyme myosin ATPase. In the presence of myosin ATPase, Ca²⁺ and Mg²⁺ ions, ATP breaks down into ADP and inorganic phosphate as

(ix) Energy from ATP causes energised myosin cross-bridges to bind to actin. The energised cross-bridge move, causing the thin myofilaments to slide along the thick myofilaments. This movement is like the movement of the oars of a boat.
(x) As stated earlier in theory, there is no shortening of thin and thick myofilaments.
However, the sarcomere shortens, because of the sliding of the thin myofilaments produced by cross-bridge movements. The H-zone and I-band shorten, but the width of the A-band remains constant.

Question. Discuss the role of Ca²⁺ ions in muscle contraction. Draw neat sketches to illustrate your answer.
Ans. Calcium plays a key regulatory role in muscle contraction. These ions bind to troponin causing change in its shape and position. This in turn alters the shape and position of tropomyosin. This shift exposes the active sites on the F-actin molecules and myosin cross-bridges able to bind to these active sites.
The complete process is outlined in the figure below

Role of calcium ion, is the contraction and relaxation process. The head of each myosin molecule contains an enzyme myosin ATPase. In the presence of myosin ATPase, Ca²⁺and Mg²⁺ ions, ATP breaks down into ADP and inorganic phosphate as

Energy from ATP causes energised myosin cross-bridges to bind with actin.

Question. Differentiate between pectoral and pelvic girdle.
Ans. The pectoral and pelvic girdle are responsible in providing support to the upper and lower body portions

Question. Calcium ion concentration in blood affects muscle contraction. Does it lead to tetany in certain cases? How will you correlate fluctuation in blood calcium with tetany?
Ans. For the muscle fibre to contract, the binding site on thin filaments must be uncovered. This occurs when Ca²⁺ bind to another set of regulatory proteins, called troponin complex which control the position of tropomyosin on the thin filament.
The calcium binding rearranges the tropomyosin, troponin complex, exposing the myosin-binding sites on the thin filament. When Ca²⁺ is present in the cytosol, the thin and thick filament slide part each other resulting in muscle contraction.
Similarly, when the Ca²⁺ concentration falls, the binding sites get covered and contraction stops.
In case of tetany there occur low calcium levels in body fluid due to diminished function of parathyroid gland. This gland is mainly involved in the secretion of parathyroid hormone which is associated in regulating calcium levels in blood. Tetany results in periodic painful muscular spasm (wild contraction) and tremors.

Question. An elderly women slipped in the bathroom and had severe pain in her lower back. After X-ray examination doctors told her it is due to a slipped disc. What does that mean? How does it affect our health?
Ans. Slipped disc is a medical condition in which spine is affected due to wear and tear in the outer fibrous ring (anulus fibrosus) of an intervertebral disc, allowing the soft, central portion to bulge out beyond the damaged outer rings.
These intervertebral disc are present between the bodies of adjacent vertebrae from the second cervical vertebra to the sacrum. This discs form strong joints that permit various movements of vertebral column and absorbs vertical shock.

The cause of slip disc can be due to general wear and tear of intervertebral disc during performing various jobs, that require constant sitting and squatting. The slipped disc or herniation occurs in two regions of body, i.e., cervical disc and lumber disc.
Slip disc in lower back lumber disc, lead to sharp pain in one part of leg due to sciatica, (disturbance in sciatic nerve), hip and cause numbness in other lower parts of the body.
Slip disc in neck region (cervical disc) leads to pain while moving neck near or over the shoulder bone or pain occurs while moving forearm, or fingers. It also causes numbness in shoulder, elbow, forearm and finger area.
Hence, slipped disc affect the upper and lower body parts, thus, influencing life style and health.

Question. How does a muscle shorten during its contraction and return to its original form during relaxation?
Ans. Formation of cross-bridge between the actin and myosin filament help muscle to contract.
(i) An ATP molecule joins the active site on myosin head of myosin myofilament. These heads contains an enzyme, myosin ATPase that along with Ca²⁺ and Mg²⁺ ions catalyses the breakdown of ATP.

(ii) The energy is transferred to myosin head which energises and straightens to join an active site on actin myofilament, forming a cross-bridge.

(iii) The energised cross-bridges move, causing the attached actin filaments to move towards the centre of A-band. The Z-line is also pulled inwards causing shortening of sarcomere, i.e., contraction. It is clear from the above explanation that during contraction A-bands retain the length, while I-bands get reduced.
(iv) The myosin head releases ADP and Pi, relaxes to its low energy state. The head detaches from actin myofilaments when new ATP molecule joins it and cross-bridge are broken.
(v) In repeating cycle, the free head cleaves the new ATP. The cycles of cross-bridge formation and breakage is repeated causing further sliding.

(vi) Muscle relaxation occurs after contraction when the calcium ions are pumped back to the sarcoplasmic cisternae, thus, blocking the active sites on actin myofilaments. The Z-line returns to original position, i.e., relaxation.