Prepare for NEET Biology Structural Organisation In Animals (Muscular Tissue) with MCQs & PYQs on NEET.GUIDE. Access free practice, previous year questions, and expert insights into skeletal, smooth, and cardiac muscles and their functions.
NEET Questions / Zoology / Structural Organisation In Animals / Muscular Tissue
A unique feature of smooth muscle fibers, unlike skeletal and cardiac muscles, is their ability to:
Contract rhythmically and spontaneously
Maintain tension over a wide range of lengths (stress-relaxation response)
Be stimulated by neurotransmitters released from somatic motor neurons
Appear striated under a microscope
Dystrophin, a protein crucial for muscle function, primarily interacts with which component of the muscle fiber?
Actin filaments of the cytoskeleton, linking them to the sarcolemma.
Myosin filaments, regulating cross-bridge cycling.
Sarcoplasmic reticulum, modulating calcium release.
Troponin-tropomyosin complex, controlling actin-myosin interaction.
Which statement accurately describes the role of caldesmon in smooth muscle contraction?
Inhibits actin-myosin interaction in the absence of by binding to actin and tropomyosin.
Phosphorylates myosin light chain kinase, initiating cross-bridge cycling.
Binds , triggering the conformational change in troponin.
Enhances the ATPase activity of myosin, promoting contraction.
The dense bodies in smooth muscle are analogous to which structure in skeletal muscle?
Z-lines
M-lines
H-zones
A-bands
Which protein is directly responsible for the latch-bridge mechanism in smooth muscle, allowing sustained contraction with low energy consumption?
Myosin light chain kinase
Calmodulin
Myosin light chain phosphatase
Actin
Mutations in which gene are MOST directly associated with familial hypertrophic cardiomyopathy, primarily affecting cardiac muscle?
Beta-myosin heavy chain
Dystrophin
Caldesmon
Connectin (titin)
Which of the following is NOT a characteristic of smooth muscle tissue?
Involuntary control
Spindle-shaped cells
Presence of dense bodies
Multinucleated fibers
The functional unit of a skeletal muscle fiber is the:
Myofibril
Sarcomere
Sarcoplasmic reticulum
T-tubule
Which protein is primarily responsible for the elasticity of muscle tissue?
Actin
Myosin
Titin
Tropomyosin
Intercalated discs are characteristic features of which muscle type?
Skeletal muscle
Smooth muscle
Cardiac muscle
Both skeletal and smooth muscle
