Why can cardiac muscle fibres contract for longer periods than skeletal fibres? (a) Cardiac muscle is self-excitatory (b) Extracellular calcium partially controls the strength (and length) of contraction (c) Cisternae of T-tubules are more developed in cardiac muscle (d) Cardiac muscle is uninucleate rather than multinucleate

Why can cardiac muscle fibres contract for longer periods than skeletal fibres? (a) Cardiac muscle is self-excitatory (b) Extracellular calcium partially controls the strength (and length) of contraction (c) Cisternae of T-tubules are more developed in cardiac muscle (d) Cardiac muscle is uninucleate rather than multinucleate
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Characteristics of smooth muscle fibres are (a) spindle-shaped, unbranched, nonstriated, uninucleate and involuntary (b) spindle-shaped, unbranched, unstriped, multinucleate and involuntary (c) cylindrical, unbranched, unstriped, multinucleate and involuntary (d) cylindrical, unbranched, striated, multinucleate and voluntary.

Description : Characteristics of smooth muscle fibres are (a) spindle-shaped, unbranched, nonstriated, uninucleate and involuntary (b) spindle-shaped, unbranched, unstriped, multinucleate and involuntary (c ... , multinucleate and involuntary (d) cylindrical, unbranched, striated, multinucleate and voluntary.

Last Answer : (a) spindle-shaped, unbranched, nonstriated, uninucleate and involuntary

The sequence of events in muscle contraction a. action potential depolarise the T-tubules b. depolarisation of T-tubules release calcium from sarcoplasmic reticulum c. calcium binds to the troponin-tropomycin complex d. all above

Description : The sequence of events in muscle contraction a. action potential depolarise the T-tubules b. depolarisation of T-tubules release calcium from sarcoplasmic reticulum c. calcium binds to the troponin-tropomycin complex d. all above

Last Answer : all above

.Acetabularia used in Hammerling’s nucleocytoplasmic experiments is (a) unicellular fungus (b) multicellular fungus (c) unicellular uninucleate green algae (d) unicellular multinucleate green algae.

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Last Answer : (c) unicellular uninucleate green algae

Smooth muscles are (a) involuntary, fusiform, non-striated (b) voluntary, multinucleate, cylindrical(c) involuntary, cylindrical, striated (d) voluntary, spindle-shaped, uninucleate.

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Last Answer : (a) involuntary, fusiform, non-striated

The four sketches (A, B, C and D) given below, represent four different types of animal tissues. Which one of these is correctly identified in the options given, along with its correct location and function? (A) (B) (C) (D) Tissue Location Function (a) (B) Glandular Intestine Secretion epithelium (b) (C) Collagen Cartilage Attach skeletal fibres muscles to bones(c) (D) Smooth Heart Heart muscle contraction tissue (d) (A) Columnar Nephron Secretion epithelium and absorption

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Last Answer : (a) (B) Glandular Intestine Secretion epithelium

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 (c) detaches the myosin head from the actin filament (d) prevents the formation of bonds between the myosin cross bridges and the actin filament.

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

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 it. (3) detaches the myosin head from the actin filament. (4) prevents the formation of bonds between the myosin cross bridges and the actin filament.

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.

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Caffeine is more powerful than theophylline in exerting the following action (a) Bronchodilatation (b) Cardiac stimulation (c) Diuresis (d) Augmentation of skeletal muscle contractility

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Match the source gland with its respective hormone and function and select the correct option. Source Hormone Function gland (a) Anterior Oxytocin Contraction of uterus pituitary muscles during child birth (b) Posterior Vasopressin Stimulates pituitary reabsorption of water in the distal tubules in the nephron (c) Corpus Estrogen Supports pregnancy luteum (d) Thyroid Thyroxine Regulates blood calcium level

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Can you control the contraction of skeletal muscle?

Description : Can you control the contraction of skeletal muscle?

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Description : What are the differences between skeletal muscle, smooth muscle, and cardiac muscle? -Biology

Last Answer : answer:

Which of the following statement(s) is/are correct concerning the cardiovascular response to shock? a. Changes in cardiac contractile function shift the Frank Starling curve up and down b. Venoconstriction from skeletal muscle is a significant contributor to the restoration of blood volume with shock c. Arterial vasoconstriction affects all vascular beds equally d. The total circulating blood volume is equally split between the arterial and venous system

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Which type of muscle is a syncytium (pron: sin-sish-E-um)? a) skeletal b) cardiac c) smooth d) all of the above

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When performing endotracheal suctioning, the nurse applies suctioning while withdrawing and gently rotating the catheter 360 degrees for which of the following time periods? a) 10-15 seconds In general, the nurse should apply suction no longer than 10-15 seconds because hypoxia and dysrhythmias may develop, leading to cardiac arrest. b) 30-35 seconds Applying suction for 30-35 seconds is hazardous and may result in the patient’s developing hypoxia, which can lead to dysrhythmias and, ultimately, cardiac arrest.

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How does a skeletal muscle contract? -Biology

Description : How does a skeletal muscle contract? -Biology

Last Answer : answer:

The following are true about potassium: a. hypokalaemia decreases the time of cardiac repolarization b. hyperkalaemia decreases cardiac contraction c. hyperkalaemia relaxes vascular smooth muscle d. all

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In the mammalian body, this element plays many important roles. Try to identify this element with the fewest number of clues. This element is required to insure the integrity and permeability of cell membranes, to regulate nerve and muscle excitability, to help maintain normal muscular contraction, and to assure cardiac rhythmicity. It also plays a essential role in several of the enzymatic steps involved in blood coagulation and is the most important element of bone salt. Name this element.

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Last Answer : ANSWER: Calcium 

A. It is a clonidine congener used in spasticity due to stroke or spinal injury B. It reduces muscle tone by activating GABAB receptors C. It inhibits release of excitatory amino-acids in spinal interneurones D. It reduces muscle spasms without producing weaknes

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The felderstrukter fibres of the extraocular musclea. form the bulk of the orbital part of the muscle b. have poorly developed sarcoplasmic reticulum c. are singly innervated d. are more richly supplied by blood than the fibrillenstrukter fibres

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Last Answer : have poorly developed sarcoplasmic reticulum

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

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

Given below is the ECG of a normal human. Which one of its components is correctly interpreted below? (a) Complex QRS - one complete pulse (b) Peak T - initiation of total cardiac contraction (c) Peak P and peak R together - systolic and diastolic blood pressures (d) Peak P- initiation of left atrial contraction only

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Can I get an MRI for a cardiac calcium score rather than a CT?

Description : Can I get an MRI for a cardiac calcium score rather than a CT?

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Last Answer : . influences the binding of drugs to plasma proteins

What is needed besides calcium for muscle contraction?

Description : What is needed besides calcium for muscle contraction?

Last Answer : Need answer

Name the ion responsible for unmasking of active sites for myosin for cross-bridge activity during muscle contraction. (a) Calcium (b) Magnesium (c) Sodium (d) Potassium

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Which one of the following is correct pairing of a body part and the kind of muscle tissue that moves it? (a) Biceps of upper arm – S m o o t h m u s c l e fibres (b) Abdominal wall – Smooth muscle (c) Iris – Involuntary smooth muscle (d) Heart wall – Involuntary unstriated muscle

Description : Which one of the following is correct pairing of a body part and the kind of muscle tissue that moves it? (a) Biceps of upper arm – S m o o t h m u s c l e fibres (b) Abdominal wall – Smooth muscle (c) Iris – Involuntary smooth muscle (d) Heart wall – Involuntary unstriated muscle

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Caffeine is more powerful than theophylline in exerting the following action: A. Bronchodilatation B. Cardiac stimulation C. Diuresis D. Augmentation of skeletal muscl contractility

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Last Answer : D. Augmentation of skeletal muscl contractility

Where is calcium released when a muscle contract?

Description : Where is calcium released when a muscle contract?

Last Answer : Need answer

In an internal mouthpiece, if the jet after contraction does not touch the sides of the mouthpiece, then the mouthpiece is said to be (A) Running full (B) Running free (C) Partially running full (D) Partially running free

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Last Answer : Answer: Option B

The autonomic nervous system innervates all of these except? A. Cardiac muscles B. Skeletal muscles (Answer) C. Smooth muscles D. none

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Last Answer : B. Skeletal muscles (Answer)

Hypocalcaemia affects (A) Skeletal muslces (B) Smooth muscles (C) Cardiac muscles (D) Skeletal muscles + smooth muscles + cardiac muscles

Description : Hypocalcaemia affects (A) Skeletal muslces (B) Smooth muscles (C) Cardiac muscles (D) Skeletal muscles + smooth muscles + cardiac muscles

Last Answer : Answer : D

Identify the tissue shown in the diagram and match with its characteristics and its location. (a) Smooth muscles, show branching, found in the wall of the heart(b) Cardiac muscles, unbranched muscles, found in the walls of the heart (c) Striated muscles, tapering at both-ends, attached with the bones of the ribs (d) Skeletal muscles show striations and are closely attached with the bones of the limbs

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Last Answer : (d) Skeletal muscles show striations and are closely attached with the bones of the limbs

Antidiuretic hormone (ADH) - (1) inhibits the secretion of growth hormone by the pituitary (2) inhibits the rate of heart beat (3) causes the muscular walls of the arterioles to contract that simulates the reabsorption of water from the kidney tubules (4) causes an increase in the blood pressure

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Last Answer : (3) causes the muscular walls of the arterioles to contract that simulates the reabsorption of water from the kidney tubules

During contraction and relaxation of striated muscle fibre the length of A band usually :-

Description : During contraction and relaxation of striated muscle fibre the length of A band usually :-

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Which statement is correct for muscle contraction? (a) Length of H-zone decreases. (b) Length of A-band remains constant. (c) Length of I-band increases. (d) Length of two Z-line increases.

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

Which of the following terms refers to muscle tension being unchanged with muscle shortening and joint motion? a) Isotonic contraction Exercises such as swimming and bicycling are isotonic. b) Isometric contraction Isometric contraction is characterized by increased muscle tension, unchanged muscle length, and no joint motion. c) Contracture Contracture refers to abnormal shortening of muscle, joint, or both. d) Fasciculation Fasciculation refers to involuntary twitch of muscle fibers.

Description : Which of the following terms refers to muscle tension being unchanged with muscle shortening and joint motion? a) Isotonic contraction Exercises such as swimming and bicycling are isotonic. b) ... , joint, or both. d) Fasciculation Fasciculation refers to involuntary twitch of muscle fibers.

Last Answer : a) Isotonic contraction Exercises such as swimming and bicycling are isotonic.

Purkinje fibres mainly help in contraction of `:-`

Description : Purkinje fibres mainly help in contraction of `:-`

Last Answer : Purkinje fibres mainly help in contraction of `:-` A. Right auricle B. Left ventricle C. Ventricles D. Aorta

The positive inotropic action of digoxin takes several hours to develop because: A. Binding of digoxin to Na+K+ATPase is slow B. After Na+K+ATPase inhibition by digoxin, Ca2+ loading of myocardial fibres occurs progressively with each contraction C. Digoxin inhibits Na+K+ATPase through modification of gene function which takes time D. Both ‘A’ and ‘B’ are correc

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Last Answer : D. Both ‘A’ and ‘B’ are correct

n a failing heart therapeutic dose of digoxin has no effect on the following parameter: A. Cardiac output B. Heart rate C. Tone of ventricular fibres D. Cardiac vagal tone

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Last Answer : C. Tone of ventricular fibres

Multicelluar, multinucleate, irregular mass of embryo which pass into uterine wall is

Description : Multicelluar, multinucleate, irregular mass of embryo which pass into uterine wall is

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.Which one of the following organelles is located near the nucleus and contains a collection of flattened membrane bound cisternae? (a) Nucleolus (b) Mitochondrion (c) Centriole (d) Golgi apparatus

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Last Answer : (d) Golgi apparatus

Match the columns and identify the correct option. Column I Column II A. Thylakoids (i) Disc-shaped sacs in Golgi apparatus B. Cristae (ii) Condensed structure of DNA C. Cisternae (iii) Flat membranous sacs in stroma D. Chromatin (iv) Infoldings in mitochondria (a) A-(iii), B-(i), C-(iv), D-(ii) (b) A-(iii), B-(iv), C-(ii), D-(i) (c) A-(iv), B-(iii), C-(i), D-(ii) (d) A-(iii), B-(iv), C-(i), D-(ii)

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Last Answer : (d) A-(iii), B-(iv), C-(i), D-(ii)

Each chloroplast encloses a system of flattened, membranous sacs called (A) Cristae (B) Thylakoids (C) Plastids (D) Cisternae

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Last Answer : (B) Thylakoids

Within chloroplasts, light is captured by (A) Grana within cisternae (B) Thylakoids within grana (C) Cisternae within grana (D) Grana within thylakoids

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The principal cation in extracellular fluid is (A) Sodium (B) Potassium (C) Calcium (D) Magnesium

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Last Answer : Answer : A

The percentage of calcium present in extracellular fluid is (A) 1 (B) 5 (C) 10 (D) 50

Description : The percentage of calcium present in extracellular fluid is (A) 1 (B) 5 (C) 10 (D) 50

Last Answer : Answer : A

Which of the following statement(s) is/are true concerning the microvascular and cellular response to shock? a. Osmodically induced mobilization of intracellular fluid is the initial response to restore intravascular volume b. With larger volume hemorrhagic shock deterioration of normal cellular transmembrane potential occurs resulting in an increase in extracellular sodium and water c. The accumulation of anaerobic metabolites override normal homeostatic vasomotor tone and contribute to the maladaptive vasodilatation d. Abnormal intracellular calcium homeostasis may contribute to the cellular dysfunction of shock

Description : Which of the following statement(s) is/are true concerning the microvascular and cellular response to shock? a. Osmodically induced mobilization of intracellular fluid is the initial ... d. Abnormal intracellular calcium homeostasis may contribute to the cellular dysfunction of shock

Last Answer : Answer: c, d Moderate hypovolemia results in a relatively rapid spontaneous restitution of intravascular volume through expansion of the plasma space. This plasma expansion by ... potassium pump. Cellular dysfunction also appears to be related to abnormal intracellular calcium homeostasis