All Free Biology MCQs with Answers

• A. Controls the tonic state of myocytes
• B. Creates an ion potential across the muscle surface
• C. Allows attachment sites for communication hormones
• D. Controls the iron levels of cardiac tissue

Explanation: Sarcolemma is not present in cardiac tissue.

• A. Myosin and Cartilage
• B. Mylode and Myosin
• C. Lamellae and Actin
• D. Actin and Myosin

Explanation: Option D is correct since Myofibrils are composed of overlapping thick ( Myosin) and thin Myofilaments (Actin) organized into sarcomeres.

• A. Bundle of connective tissue
• B. Bundle of myofibrils
• C. Bundle of muscle fibres
• D. Muscle cells

Explanation: Correct option: CIt is taken directly from the definition of muscle fascicle.A muscle fascicle is a bundle of muscle fibres (also known as…

• A. Synchondroses
• B. Sutures
• C. Gomphosis
• D. All of these

Explanation: Correct Option :DThis option is correct because it covers all the other correct options.As structural classification is the grouping or…

• A. Collagen
• B. Myosin
• C. Titin
• D. Actin and myosin

Explanation: Titin is a massive protein that spans the length of half of a sarcomere (from the Z-disc to the M-line) and allows for the passive…

• A. Shank
• B. Upper arm
• C. Shoulder
• D. Lower jaw

Explanation: The biceps are located on the front of the upper arm and provide arm flexion, while the triceps are found on the back of the upper arm and…

• A. Fibrous joint
• B. Cartilagenous joint
• C. Hinge joint
• D. Ball and socket joint

Explanation: A hinge joint is a type of synovial joint that allows movement primarily in two direction, resembling the action of a hinge on a door.

• A. Ellipsoidal
• B. Gomphosis
• C. Syndesmosis
• D. None of these options are correct

Explanation: Classification of joints is given below:

• A. ACP
• B. ADP
• C. NAD
• D. ATP

Explanation: ATP is hydrolyzed into its simpler form ADP + P during muscle contraction.

• A. ATP synthase
• B. ADP synthase
• C. ADP hydrolase
• D. ATP hydrolase

Explanation: Myosin is an ATPase enzyme that (in myosin head) hydrolyzes an ATP molecule, hence it is categorized as an ATP hydrolase.

• A. Tendon
• B. Ligament
• C. Reticular tissue
• D. Cartilage

Explanation: A ligament is a fibrous connective tissue that attaches bone to bone.

• A. Sarcolemma
• B. Sarcoplasm
• C. Sarcophagus
• D. Sarcomere

Explanation: The region between two Z lines is called a sarcomere.

• A. Sarcomere
• B. Sarcoplasmic reticulum
• C. Actin
• D. Myosin

Explanation: The sarcomere is the fundamental unit of contraction and is defined as the region between two Z-lines.

• A. The thin filament
• B. Both
• C. Thick filament
• D. None

Explanation: The thick filament consists largely of myosin. Six proteins make up myosin: two heavy chains whose tails intertwine to form a supercoil…

• A. Z line
• B. A band
• C. M line
• D. H zone

Explanation: A sarcomere is the contractile unit of the muscle. Thick and thin filaments in a sarcomere overlap during muscle contraction.

• A. Myofilaments
• B. Sarcoplasmic reticulum
• C. Z-lines
• D. Transverse tubules

Explanation: Transverse tubules: This option is the correct answer. The sarcolemma of a muscle fiber folds inwards at regular intervals to form…

• A. I-bands shorten
• B. H-zone becomes more visible
• C. Z-lines move further apart
• D. A-bands shorten

Explanation: I-bands shorten: This option is the correct answer. According to the sliding filament theory, when muscle fibers are stimulated by the…

• A. Appendicular skeleton
• B. Exoskeleton
• C. Endoskeleton
• D. Hydrostatic skeleton

Explanation: The human skeleton consists of the axial skeleton, which comprises of the cranium, backbone, and ribs, and the appendicular skeleton…

• A. Sacrum
• B. Cervical vertebrae
• C. Pubis
• D. Coccyx

Explanation: The last 4 vertebrae in humans are fused into a triangular structure known as the coccyx.

• A. 3 bones
• B. 4 bones
• C. 2 bones
• D. 1 bone

Explanation: Each half of the pelvic girdle comprises of 3 bones; the ilium, the pubis, and the ischium.