{"id":120312,"date":"2022-05-09T17:13:09","date_gmt":"2022-05-09T11:43:09","guid":{"rendered":"https:\/\/www.mapsofindia.com\/my-india\/?p=120312"},"modified":"2022-05-09T17:13:09","modified_gmt":"2022-05-09T11:43:09","slug":"chapter-20-locomotion-and-movement-questions-and-answers-ncert-solutions-for-class-11-biology","status":"publish","type":"post","link":"https:\/\/www.mapsofindia.com\/my-india\/education\/chapter-20-locomotion-and-movement-questions-and-answers-ncert-solutions-for-class-11-biology","title":{"rendered":"Chapter 20 – Locomotion and Movement Questions and Answers: NCERT Solutions for Class 11 Biology"},"content":{"rendered":"

1. Draw the diagram of a sarcomere of skeletal muscle showing different regions.<\/h2>\n

Solution:
\nThe diagram below shows the sarcomere of skeletal muscle showing different regions:<\/h3>\n

\"\"<\/p>\n

2. Define sliding filament theory of muscle contraction.<\/h2>\n

Solution:
\nSliding filament theory states that the muscle fibre contraction occurs due to the sliding of the thin filaments over thick filaments.<\/h3>\n

3. Describe the important steps in muscle contraction.<\/h2>\n

Solution:
\nThe mechanism of muscle contraction is explained well by the sliding filament theory which states that the muscle fibre contraction occurs due to the sliding of the thin filaments over the thick filaments.<\/h3>\n

\"\"<\/p>\n

\"\"<\/p>\n

Mechanism of muscle contraction:
\nStep 1 \u2013 Depolarization of Sarcolemma
\n1. The central nervous system (CNS) sends a signal through a motor neuron which arrives at the neuromuscular junction or the motor end plate
\n2. The junction present between the sarcolemma of the muscle fiber and the motor neuron is called the neuromuscular junction
\n3. The release of a neurotransmitter called acetylcholine is triggered when the signal arrives at the neuromuscular junction. The action potential in the sarcolemma is set by this release.
\nStep 2 \u2013 Release of Calcium ions
\n1. The sarcolemma transmits the action potential to the sarcoplasmic reticulum in order to release the calcium ions in the sarcoplasm
\nStep 3 \u2013 Conformational changes occurs in the Actin filaments
\n1. The calcium ions that are released, tends to bind to the troponin and tropomyosin located on the active filaments
\n2. This linkage causes a modification in the three-dimensional structure of the actin-troponin-tropomyosin complex. The active site for myosin which is located on the actin filament is exposed.
\nStep 4 \u2013 Activation of Myosin heads
\n1. The calcium ions release causes the myosin heads to get activated which inturn causes the release of energy in the form of ATP
\n2. Hydrolysis of ATP releases energy which causes the binding of myosin heads to the active sites found on the actin filaments hence forming a cross-bridge
\nStep 5 \u2013 Actin Filaments slide over Myosin
\n1. The myosin head rotates due to the formation of cross-bridge, pulling the actin filaments to the centre of the A-band which is the H-zone
\n2. The z-line which is attached to the actin filaments is pulled inwards too
\n3. Contraction of sarcomere occurs when the actin filaments are pulled in the opposite ends
\n4. During the process of contraction, the I-band shortens whereas the A-band maintains its length causing the muscles to contract.<\/h3>\n

4. Write true or false. If false change the statement so that it is true.
\n(a) Actin is present in thin filament
\n(b) H-zone of striated muscle fibre represents both thick and thin filaments.
\n(c) Human skeleton has 206 bones.
\n(d) There are 11 pairs of ribs in man.
\n(e) Sternum is present on the ventral side of the body.<\/h2>\n

Solution:
\n(a) Actin is present in thin filament \u2013 True
\n(b) H-zone of striated muscle fibre represents both thick and thin filaments \u2013 False
\nCorrected statement: H-zone of the striated muscle fiber represents only thick filaments
\n(c) Human skeleton has 206 bones \u2013 True
\n(d) There are 11 pairs of ribs in man \u2013 False
\nCorrected statement: There are 12 pairs of ribs in man.
\n(e) Sternum is present on the ventral side of the body \u2013 True<\/h3>\n

5. Write the difference between:
\n(a) Actin and Myosin
\n(b) Red and White muscles
\n(c) Pectoral and Pelvic girdle<\/h2>\n

Solution:
\nThe differences are as follows:
\na) Actin and myosin
\nActin
\nMyosin
\nThin filaments (I-bands) of the myofilament are formed
\nThick filaments (A-bands) of the myofilament are formed
\nIt is built of globular actin monomers
\nIt is built of meromyosin monomers
\nThe regulatory proteins Tropnin and tropomyosin are linked with the actin
\nThe regulatory proteins are not linked, instead each of the meromyosin is built of four light chains and two identical heavy chains
\nb) Red and white muscles
\nParameters
\nRed muscles
\nWhite muscles
\nMyoglobin content
\nHigh
\nLow
\nAmount of sarcoplasmic reticulum
\nModerate
\nHigh
\nFibers
\nNarrow and thin
\nBroad and thick
\nMitochondria
\nPossess many
\nFew
\nFatigue
\nNot fatigued
\nFatigued
\nType of respiration from which energy is derived
\nAerobic
\nAnaerobic
\nc) Pectoral and Pelvic girdle
\nPectoral girdle
\nPelvic girdle
\nPectoral girdle is called as the shoulder girdle
\nPelvic girdle is called as the hip girdle
\nEach part\/half of the girdle consists of two bones \u2013 clavicle and scapula
\nEach part\/half of the girdle consists of three bones \u2013 ischium, ilium and pubis
\nForelimb articulation is offered
\nHindlimb articulation is offered
\nHead of the humerus articulates with the glenoid cavity of the pectoral girdle
\nHead of the femur articulates with the acetabulum of the pelvic girdle<\/h3>\n

6. Match Column I with Column II:
\nColumn I
\nColumn II
\n(a) Smooth muscle
\n(i) Myoglobin
\n(b) Tropomyosin
\n(ii) Thin filament
\n(c) Red muscle
\n(iii) Sutures
\n(d) Skull
\n(iv) Involuntary<\/h2>\n

Solution:
\nColumn I
\nColumn II
\n(a) Smooth muscle
\n(iv) Involuntary
\n(b) Tropomyosin
\n(ii) Thin filament
\n(c) Red muscle
\n(i) Myoglobin
\n(d) Skull
\n(iii) Sutures<\/h3>\n

7. What are the different types of movements exhibited by the cells of human body?<\/h2>\n

Solution:
\nMovement is considered to be one of the fundamental characteristics which is observed in the living entities. The different types of movements exhibited by the human body cells are:
\n1. Amoeboid Movement \u2013 Leucocytes found in blood exhibit this type of movement. Leucocytes from the circulatory system move towards the injury site when there is a damage to the tissue in order to initiate an immune response.
\n2. Muscular movement \u2013 The muscle cells exhibit this type of movement
\n3. Ciliary movement \u2013 Sex cells (sperms and ova) exhibit this type of movement. This movement facilitates the passage of ova via the fallopian tube on its way to the uterus.<\/h3>\n

8. How do you distinguish between a skeletal muscle and a cardiac muscle?<\/h2>\n

Solution:
\nThe differences between a skeletal muscle and a cardiac muscle is as follows:
\nSkeletal muscle
\nCardiac muscle
\nLinked to the primary bones
\nLocated in the walls of the heart
\nVoluntary in nature
\nInvoluntary in nature
\nPeripherally located nucleus
\nCentrally located nucleus
\nThe muscle fibers of the skeletal muscles are unbranched
\nThe muscle fibers of the cardiac muscles are branched
\nIntercalated discs are not found in the Muscle fibers of the skeletal muscles
\nIntercalated discs are found in the muscle fibers of the cardiac muscles
\nBrings about the locomotory actions of the body and maintains body posture
\nResponsible for the movement\/motion of the heart<\/h3>\n

9. Name the type of joint between the following:-
\n(a) atlas\/axis
\n(b) carpal\/metacarpal of thumb
\n(c) Between phalanges
\n(d) femur\/acetabulum
\n(e) Between cranial bones
\n(f) Between pubic bones in the pelvic girdle<\/h2>\n

Solution:
\nThe types of joints are as follows:
\n(a) atlas\/axis \u2013 Pivot joint
\n(b) carpal\/metacarpal of thumb \u2013 Saddle joint
\n(c) Between phalanges \u2013 Hinge joint
\n(d) femur\/acetabulum \u2013 Ball and socket joint
\n(e) Between cranial bones \u2013 Fibrous joint
\n(f) Between pubic bones in the pelvic girdle \u2013 cartilaginous joint<\/h3>\n

10. Fill in the blank spaces:
\n(a) All mammals (except a few) have __________ cervical vertebra.
\n(b) The number of phalanges in each limb of human is __________
\n(c) Thin filament of myofibril contains 2 \u2018F\u2019 actins and two other proteins namely____ and _____.
\n(d) In a muscle fibre Ca++ is stored in __________
\n(e) __________ and __________ pairs of ribs are called floating ribs.
\n(f) The human cranium is made of __________ bones<\/h2>\n

Solution:
\n(a) Seven
\n(b) Fourteen
\n(c) Troponin, tropomyosin
\n(d) Sarcoplasmic reticulum
\n(e) Eleventh, twelfth
\n(f) Eight<\/h3>\n","protected":false},"excerpt":{"rendered":"

Class 11 Biology NCERT book solutions for Chapter 20 – Locomotion and Movement Questions and Answers.<\/p>\n","protected":false},"author":21830,"featured_media":120091,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":{"0":"post-120312","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-education"},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts\/120312","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/users\/21830"}],"replies":[{"embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/comments?post=120312"}],"version-history":[{"count":1,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts\/120312\/revisions"}],"predecessor-version":[{"id":120316,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts\/120312\/revisions\/120316"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/media\/120091"}],"wp:attachment":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/media?parent=120312"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/categories?post=120312"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/tags?post=120312"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}