The H-disk in the skeletal muscle fibre is due to (a) the absence of myofibrils in the central portion of Aband (b) the central gap between myosin filaments in the Aband Questions (c) the central gap between actin filaments extending through myosin filaments in the A-band (d) birefringence of myosin filaments in the central portion of A-band

1 Answer

Answer :

Ans:(c)

Related questions

Description : The H-zone in the skeletal muscle fibre is due to (a) the central gap between actin filaments extending through myosin filaments in the A-band (b) extension of myosin filaments in the central portion ... the central portion of A-band (d) the central gap between myosin filaments in the A-band.

Last Answer : (a) the central gap between actin filaments extending through myosin filaments in the A-band

Description : With reference to the skeletal muscle myofilaments a. actin is the major constituent of thin filaments b. myosin and tropomyosin combine to form the thick filaments c. troponin is a constituents of thin filaments d. tropomyosin prevents the interaction of actin and myosin in the resting state

Last Answer : actin is the major constituent of thin filaments

Description : During muscle contraction in humans, the (a) sarcomere does not shorten (b) A band remains same (c) A, H and I bands shorten (d) actin filaments shorten.

Last Answer : (b) A band remains same

Description : In the skeletal muscle: a. myosin is found in the thick filament b. the thin filament contains actin and troponin c. during stimulus excitation calcium ions are derived from the serum d. tropomyosin masks the myosin-combining sites on the actin

Last Answer : tropomyosin masks the myosin-combining sites on the actin

Description : Calcium is important in skeletal muscle contraction because it (a) binds to troponin to remove the masking of active sites on actin for myosin (b) activates the myosin ATPase by binding to it ... filament (d) prevents the formation of bonds between the myosin cross bridges and the actin filament.

Last Answer : (a) binds to troponin to remove the masking of active sites on actin for myosin

Description : Calcium is important in skeletal muscle contraction because it :- (1) binds to troponin to remove the masking of active sites on actin for myosin. (2) activates the myosin ATPase by binding to ... filament. (4) prevents the formation of bonds between the myosin cross bridges and the actin filament.

Last Answer : (1) binds to troponin to remove the masking of active sites on actin for myosin.

Description : Select the correct statement regarding the specific disorder of muscular or skeletal system. (a) Muscular dystrophy - Age related shortening of muscles (b) Osteoporosis - Decrease in bone mass and ... of myosin filaments (d) Gout - Inflammation of joints due to extra deposition of calcium

Last Answer : (b) Osteoporosis – Decrease in bone mass and higher chances of fractures with advancing age

Description : Sliding filament theory can be best explained as (a) actin and myosin filaments do not shorten but rather slide pass each other (b) when myofilaments slide pass each other, myosin filaments shorten ... filaments do not shorten (d) actin and myosin filaments shorten and slide pass each other.

Last Answer : (a) actin and myosin filaments do not shorten but rather slide pass each other

Description : The organic portion of bone consists of which one of the following proteins. a) fibrin b) collagen c) actin d) myosin

Last Answer : ANSWER: B -- COLLAGEN

Description : The H-zone in the skeletal muscle fibre is due to

Last Answer : The H-zone in the skeletal muscle fibre is due to A. the absence of myofibrils in the central ... filaments in the central portion of the A-band.

Description : Myosin bridges can be prevented from combining actin by two regulator proteins in resting muscle by (a) troponin (b) myofibril (c) troponin and tropomyosin (d) natural inhibiting proteins

Last Answer : Ans:(c)

Description : The contractile proteins in a muscle are (1) Actin and Myosin (2) Actin and Tropomyosin (3) Myosin and Troponin (4)Troponin and Tropomyosin

Last Answer : (1) Actin and Myosin Explanation: Muscle fibers or myofibrils are formed of three types of proteins which are (1) contractile, (2) regulatory, and (3) structural. Contractile proteins are the force ... are Actin which is part of thin filament and Myosin, which is part of the thick filament.

Description : The following are true about the smooth muscle cells: a. presence of a striated appearance b. do not contain actin and myosin c. spontaneous muscle contraction d. mitochondria are absent

Last Answer : spontaneous muscle contraction

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Last Answer : spontaneous muscle contraction

Description : Which one of the following is the correct matching of three items and their grouping category? Items Group (a) Ilium, ischium, Coxal bones of pelvic girdle pubis (b) Actin, myosin, Muscle proteins rhodopsin (c) Cytosine, uracil, Pyrimidines thiamine (d) Malleus, incus, Ear ossicles cochlea

Last Answer : (a) Ilium, ischium, Coxal bones of pelvic girdle pubis

Description : The phase of contraction of a muscle occurs when: a) tropomyosin binds and releases actin b) myosin binds and releases actin c) actin binds and releases myosin d) none of the above

Last Answer : ANSWER: B -- MYOSIN BINDS AND RELEASES ACTIN

Description : The contractile proteins in a muscle are (1) Actin and Myosin (2) Actin and Tropomyosin (3) Myosin and Troponin (4) Troponin and Tropomyosin

Last Answer : Actin and Myosin 

Description : Myosin is one of two proteins that make up the myofibrils of striated muscles. Name the other protein.

Last Answer : ANSWER: Actin

Description : The contractile protein of skeletal muscle involving ATPase activity is (a) troponin (b) tropomyosin (c) myosin (d) α-actinin.

Last Answer : (c) myosin

Description : The segment of a myofibril that is called a sarcomere runs from (a) one Z-line to the next Z-line (b) one A-band to the next A-band (c) one H-zone to the next H-zone (d) one end of a skeletal muscle to the opposite end

Last Answer : Ans:(a)

Description : A characteristic feature of a muscle fibre is the presence of large number of parallel arranged filaments in the sarcoplasm called_____

Last Answer : A characteristic feature of a muscle fibre is the presence of large number of parallel arranged filaments in the sarcoplasm called_____

Description : Myosin filaments are localized in

Last Answer : Myosin filaments are localized in A. Z band B. H band C. A band D. None of the above

Description : The number of thick myofilaments (myosin) surrounding Single thin myofilament (actin) are

Last Answer : The number of thick myofilaments (myosin) surrounding Single thin myofilament (actin) are A. 3 B. 6 C. 2 D. 4

Description : A protein having both structural and enzymatic traits is (A) Myosin (B) Collagen (C) Trypsin (D) Actin

Last Answer : Answer : A

Description : The protein present in the finger nail is (1) Actin (2) Myosin (3) Globin (4) Keratin

Last Answer : (4) Keratin Explanation: Keratin is a fibrous protein making up most cells found in our nails and hair and the epidermis layer of our skin. It also makes up fish scales and crustacean shells, bird feathers and beaks, and animal horns and hooves.

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Last Answer : c) Actomyosin

Description : Microtubules consist of helically stacked molecules of the protein (A) Actin (B) Myosin (C) Keratin (D) Tubulin

Last Answer : (D) Tubulin

Description : The major fibrous proteins are: a) peptone and edestin b) glutelin and leucine c) valine and lysine d) myosin and actin

Last Answer : ANSWER: D -- Myosin and Actin

Description : The myofilaments of muscles consist primarily of two proteins. These two proteins are called: a) actin and myosin b) progesterone and testosterone c) progesterone and estrogen

Last Answer : ANSWER: A -- ACTIN AND MYOSIN

Description : The protein present in the finger nail is (1) Actin (2) Myosin (3) Globin (4) Keratin

Last Answer : Keratin

Description : The activities of the cytoskeleton is dependent on which of the following types of filaments? a. Microtubules b. Intermediate filaments c. Actin filaments d. None of the above

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Description : What is the function of proteins like microtubules and actin filaments?

Last Answer : Give structure to cells.

Description : Dantrolene sodium reduces skeletal muscle tone by: A. Reducing acetylcholine release from motor nerve endings B. Suppressing spinal polysynaptic reflexes C. Inhibiting the generation of muscle action potential D. Reducing Ca2+ release from sarcoplasmic reticulum in the muscle fibre

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Description : Which term is the smallest subdivision in this group? (a) Fibre (b) Fibril (c) Filament (d) Myosin

Last Answer : Ans:(c)

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Description : Light bands of muscle fiber consist of filaments called____whereas dark bands consist of filaments called_____

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Description : Which of the following is the form of mis-description? g) Incorrect Origin c) Incorrect quantitative description h) Extending the food d) All of the above

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Last Answer : Dark bands of myofibrils are known as____band.

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Last Answer : (b) Length of A-band remains constant.