FREE NEET Biology Practice MCQ Test: Locomotion And Movement Exercise 2 Questions Answers With Detailed Explanations [PDF]

Answer: (c)

A - III, B - I, C - IV, D - VI , E - VII

Answer: (d)

Smooth muscles are not branched and cylindrical in appearance. Involuntary muscles are striated.

Answer: (d)

Answer: (c)

Muscular dystrophy is characterised by progressive skeletal muscle weakness, defects in muscle proteins and the death of muscle cells and tissue.

Myasthenia gravis is an autoimmune neuromuscular disease in which muscle becomes weak, which is caused by circulating antibodies that block acetylcholine receptors at the postsynaptic neuromuscular junction inhibiting the excitatory effects of the acetylcholine. Gout is inflammation of joints which is caused by elevated levels of uric acid in the blood which crystallises and the crystals are deposited in joints, tendons and surrounding tissues.

Answer: (c)

Stapes is one of the three ear ossicles in the middle ear resembling a tiny stirrup. It transmits sound vibrations from the incus to the internal ear.

Answer: (d)

Answer: (d)

A striated muscle fibre is bounded by sarcolemma. It shows alternating dark and light cross bands, the striations. Dark band is called A band which has at its middle a light zone termed H zone. Light band is known as I band which is crossed through its centre by a dark membrane called Z line. The part of the muscle fibre between two successive Z lines functions as a contractile unit called sarcomere.

Answer: (c)

Fatigue (also called exhaustion, tiredness etc) is a feeling of tiredness which is distinct from weakness, and has a slow onset. They have physical or mental causes. Physical fatigue is the temporary inability of a muscle to maintain optimal physical performance, and is made more severe by intense physical exercise. Mental fatigue is a temporary decrease in maximal cognitive performance resulting from prolonged periods of cognitive activity.

Answer: (c)

ATP provides energy that is used to detach myosin from actin.

Answer: (a)

Intervertebral disc is found in the vertebral column of mammals. These discs are present between the bodies of adjacent vertebrae from second cervical vertebra to the sacrum. Each disc consists of an outer fibrous ring made at fibrocartilage and an inner soft pulpy, highly elastic substance.

These discs are majorly involved in formation of strong joints that permit various movements of the vertebral column and absorb vertical shocks.

Intervertebral disc is not found in the vertebral column of birds reptiles or amphibians.

Answer: (a)

Pterygoid is a process that extends from sphenoid bone of skull to form a Plate-like structure. Above the glenoid cavity of scapula is present two processes - acromion and coracoid. Coracoid process is like a hook and is smaller than acromion process projecting upwards. Atlas is first cervical vertebrae. Arytenoid is a cartilage that forms part of larynx.

Answer: (c)

Long bones strengthen the legs and arms, provide support and also synthesise erythrocytes and leucocytes due to presence of bone marrow in their cavities.

Answer: (c)

Decreased levels of estrogen is a common cause of osteoporosis. Osteoporosis is a condition in which the bones become brittle and fragile from loss of tissue, typically as a result of hormonal changes or deficiency of calcium or vitamin D. Osteoporosis is characterized by low bone mass and deterioration of bone tissue. This leads to increased bone fragility and risk of fracture (broken bones), particularly of the hip, spine, wrist and shoulder. Osteoporosis is often known as "the silent thief" because bone loss occurs without symptoms.

Answer: (a)

Sustained contraction with no relaxation phase is called muscle tetanus.

Answer: (b)

Hyoid is a horseshoe-shaped (or U shaped) bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies at the level of the base of the mandible in the front and the third cervical vertebra ($C_{3}$) behind. The hyoid bone provides attachment to the muscles of the floor of the mouth and the tongue above, the larynx below, and the epiglottis and pharynx behind. The hyoid bone helps in tongue movement and swallowing.

Answer: (b)

Answer: (c)

Answer: (a)

Answer: (a)

Fast muscle fibres contract spontaneously and reach anaerobic conditions in shorter time, so as to accumulate lactic acid in the muscles in shorter time.

Slow muscle fibres have a better ability to endure, as they are resistant to fatigue and contract slowly, due to accumulation of a large amount of myoglobin in them.

Actin filaments form the isometric band in the muscle fibre because it is the only actin protein which is present in that region.

Sarcomere is the contractile unit of the skeletal muscle.

Answer: (d)

Knee joint is an example of hinge joint. The knee joint joins the thigh with the leg and consists of two articulations: one between the femur and tibia, and one between the femur and patella. It is the largest joint in the human body. Hinge joint allows the movements only in a single plane. In this particular end of one bone is deeper convex and that of other is deeper concave.