LOCOMOTION AND MOVEMENT

2020 MARCH

1. Name the portion of the myofibril between two successive Z-lines. (Score 1)

(a) H-zone

(b) Sarcomere
(c) I-band

   (d) M-line

  ✔️Answer:

   (b) Sarcomere

2. Cells of human body perform different types of movement. Write any two types of movement and the parts that exhibit the movement. (Score 2)

  ✔️Answer:

Amoeboid movement: E.g. Macrophages & leucocytes.
Ciliary movement: E.g. ciliary movements in trachea.

2019 JULY

1. Name-of the bones of appendicular skeleton are given below. (Score 2)
   (a) Select the bones of pectoral girdle.
   (b) Name the articulating cavity between femur and pelvic girdle

  ✔️Answer:

   (a) Clavicle, Scapula.
   (b) Acetabulum.

2. Major steps involved in muscle contraction are given below, which are not in the correct order. Arrange them in the correct order. (Score 2)

   a. Remove the mask of active sites for binding myosin
                       ↓
   b. A signal sent out by CNS
                       ↓
   c. Binding of Ca2+ with troponin
                       ↓
   d. Release of a neuro-transmitter substance
                        ↓
   e. Release of Ca2+ into the sarcoplasm

  ✔️Answer:

   a. A signal sent out by CNS
                       ↓
   b. Release of a neuro-transmitter substance
                       ↓
   c. Release of Ca2+ into the sarcoplasm
                       ↓
   d. Binding of Ca2+ with troponin
                       ↓
   e. Remove the mask of active sites for binding myosin

2019 MARCH

1. Observe the figures given below:

   a) Identify figure 'A' and 'B'.
   b) Name the subunits of 'A' and 'B'. (Score 2)

  ✔️Answer:

(a) A= Actin, B= Myosin.
(b) A= G- actin, B= Meromyosin (HMM + LMM)

2019 MODEL

1. Complete the division of human skeletal system by- filling the blanks. (Score 2)

✔️Answer:

   (a) Axial
   (b) Vertebral column
   (c) 12
   (d) 1

2018 AUGUST

1. Identify the disorders based on the symptoms given below. (Score 2)

   a. Inflammation of joints.
   b. Decreased bone mass and increased chance of fracture.
   c. Inflammation of joints due to the accumulation of uric acid crystals.
   d. Rapid spasms in muscles due to low Ca++ in body fluids.

  ✔️Answer:

   (a) Arthritis
   (b) Osteoporosis
   (c) Gout
   (d) Tetany

2. Select the WRONG statement regarding muscles from those given below and correct it. (Score 2)

   a. Each muscle fibre is lined by the plasma membrane called sarcolemma.
   b. The light bands are called 'A' band or Anisotropic band.
   c. The Portion of the myofibril between two successive 'Z' lines is called a sarcomere.
   d. Muscle contains a red coloured oxygen storing Pigment is called' myoglobin.

  ✔️Answer:

b. The light bands are called ‘A’ band or Anisotropic band.
Correction: The light bands are called ‘I’ band or Isotropic band.

2018 MARCH

1. Select the bones of the leg from the given list of bones. (Score 2)

Humerus, Tibia, Radius, Femur, Tarsals, Ulna, Fibula, Carpels

✔️Answer:

Tibia, Femur, Tarsals, Fibula.

2018 MODEL

1. How does the increased level of calcium ion in the sarcoplasm help in muscle contraction? (Score 2)

✔️Answer:

Ca ion binds with a subunit of troponin on actin filaments and unmask the active sites for myosin.
Using energy from ATP hydrolysis, myosin head binds to active sites on the actin to form cross bridge.

2. Certain disorders and their causes are given. Match them suitably. (Score 2)

· Myasthenia gravis	· Inflammation of joints.
· Tetany	· Autoimmune disorder.
· Muscular dystrophy	· Low calcium ions in body fluid.
	· Genetic disorder.

✔️Answer:

· Myasthenia gravis	· Autoimmune disorder.
· Tetany	· Low calcium ions in body fluid.
· Muscular dystrophy	· Genetic disorder.

2017 JULY

1. An athlete met an accident on the ground. His thigh bone slipped off from the girdle.

   a. Write the name of the above-mentioned girdle?
   b. Identify the type of joint that slipped off?
   c. Name the disorder caused due to the accumulation of uric acid crystals in such a joint? (Score 2)

✔️Answer:

   (a) Pelvic girdle.
   (b) Ball and socket joint.
   (c) Gout.

2017 MARCH

1. Compete the following chart showing structure of myosin filament and its protein based on the hints given in the brackets. (Score 2)

(Light meromyosin, Actin, Tropomyosin, Meromyosin)

  ✔️Answer:

   (A) Meromyosin
   (B) Light meromyosin

2016 MARCH

1. “A contracted muscle becomes shorter and thicker but its volume remains the same.” (Score 2)

   a) Which theory explains the process of muscle contraction?
   b) Identify two contractile proteins seen in muscle.

  ✔️Answer:

   (a) Sliding Filament Theory.
   (b) Actin and Myosin.

2015 SEPTEMBER (IMPROVEMENT)

1. Based on the diagram given below, can you write down the structural changes occurring in sarcomeres during muscular contraction? (Hint: Any 2 changes) (Score 2)