Locomotion and Movement MCQs

Which of the following statements regarding cellular and organismal movements are correct?

I. Streaming of protoplasm in unicellular organisms like Amoeba is a simple form of movement.
II. Paramoecium utilizes cilia solely for locomotory purposes to change its physical location.
III. Hydra can employ its tentacles both for capturing prey and for performing locomotory movements.
IV. All locomotions are movements, and likewise, all movements are categorized as locomotions.

Consider the following statements about amoeboid and ciliary movements in the human body:

I. Macrophages and leucocytes in the blood exhibit amoeboid movement facilitated by pseudopodia.
II. Cytoskeletal elements like microfilaments are actively involved in maintaining amoeboid movement.
III. Ciliary movement is characteristic of internal tubular organs lined by stratified squamous epithelium.
IV. The coordinated movement of cilia in the trachea is responsible for transporting inhaled dust and foreign substances outwards.

Select the correct combination of statements regarding ciliary and flagellar movements:

I. Flagellar movement facilitates the swimming of spermatozoa in humans.
II. Flagellar movement maintains the water current inside the canal system of sponges.
III. Flagellar movement is involved in the locomotion of the protist Euglena.
IV. Passage of ova through the female reproductive tract is facilitated by flagellar movement of the tubal lining.

Read the following statements concerning skeletal muscle properties and organization:

I. Muscle is a specialized tissue of ectodermal origin that makes up about 40–50% of adult human body weight.
II. Skeletal muscle cells exhibit properties of excitability, contractility, extensibility, and elasticity.
III. The activities of skeletal muscles are under the voluntary control of the somatic nervous system.
IV. Under the microscope, skeletal muscles appear completely smooth and non-striated.

Analyze these statements about visceral and cardiac muscles:

I. Visceral muscles are located in the inner walls of hollow visceral organs such as the digestive tract and reproductive tract.
II. Visceral muscles exhibit strong striations and are under the direct voluntary control of the nervous system.
III. Cardiac muscle cells assemble in a branching pattern to form the heart musculature.
IV. Cardiac muscles are striated in appearance but involuntary in terms of nervous regulation.

Which of the following statements regarding the structural organization of skeletal muscle are true?

I. Each organized skeletal muscle consists of several muscle bundles called fascicles.
II. Fascicles are held together by a common collagenous connective tissue layer termed fascia.
III. Each muscle bundle contains a number of muscle cells (muscle fibres).
IV. The plasma membrane lining a muscle fibre is called the sarcolemma, which encloses the sarcoplasm.

Identify the correct statements regarding the internal structure of a muscle fibre:

I. Sarcoplasm contains multiple nuclei, making the skeletal muscle fibre a syncytium.
II. Sarcoplasmic reticulum is a highly modified rough endoplasmic reticulum that acts as a storehouse of sodium ions.
III. The myofibrils exhibit a characteristic striated appearance due to the distribution of actin and myosin.
IV. The light bands are known as 'A' or Anisotropic bands, whereas the dark bands are called 'I' or Isotropic bands.

Select the correct statements regarding the molecular arrangement of bands in myofibrils:

I. Actin filaments are thinner than myosin filaments and are commonly referred to as thin filaments.
II. Myosin filaments are thick filaments localized in the 'A' band region.
III. The elastic fibre that bisects each 'I' band is the 'Z' line, which firmly anchors the thin filaments.
IV. Thick filaments in the 'A' band are held together in the middle of the band by a thin fibrous membrane called the 'M' line.

Which of the following statements correctly describe the resting sarcomere?

I. The portion of the myofibril between two successive 'Z' lines is the functional unit of contraction called the sarcomere.
II. In a resting state, the thin filaments completely overlap the thick filaments across their entire length.
III. The central part of the thick filaments not overlapped by thin filaments is designated as the 'H' zone.
IV. The 'H' zone contains both actin and myosin filaments in a resting muscle.

Read the statements regarding the molecular structure of thin filaments (actin):

I. Each thin filament contains two filamentous 'F' actins helically wound around each other.
II. 'F' actin is a polymer composed of monomeric 'G' (globular) actins.
III. Two filaments of tropomyosin run close to the 'F' actins throughout their entire length.
IV. A complex protein, troponin, is distributed at irregular intervals on the 'F' actin polymer.