During muscular contraction, which of the following events occur?
(a) 'H' zone disappears
(b) 'A' band widens
(c) 'I' band reduces in width
(d) Myosin hydrolyzes ATP, releasing the ADP and Pi
(e) Z-lines attached to actins are pulled inwards
Choose the correct answer from the options given below.
1. (b), (c), (d), (e) only
2. (b), (d), (e), (a) only
3. (a), (c), (d), (e) only
4. (a), (b), (c), (d) only
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Cells of human body exhibit three main types of movements. Cytoskeleton elements called microfilaments play an important role in:
A. Amoeboid movements
B. Ciliary movements
C. Muscular movements
1. | Only A | 2. | Only A and B |
3. | Only A and C | 4. | A, B and C |
Pelvic girdle consists of two coxal bones [page 311; para 3]. Each coxal bone articulates with:
A. Sacrum
B. Head of femur
C. Other coxal bone
1. | Only A | 2. | Only A and B |
3. | Only A and C | 4. | A, B and C |
Match the type of muscle shown in Column I with location in Column II and select the correct match from the codes given:
COLUMN I | COLUMN II | ||
A | P | ||
B | Q | ||
C | R |
A | B | C | |
1. | P | Q | R |
2. | P | R | Q |
3. | Q | R | P |
4. | Q | P | R |
The structure shown in the given diagram is a:
1. Muscle fibre
2. Myofibril
3. Myofilament
4. Myoblasts
Identify the incorrectly matched pair:
1. | Occipital bone | Cranial bone that has condyles for articulation with superior region of the vertebral column |
2. | Ethmoid | Cranial bone forming the superior roof of the nasal cavity |
3. | Sphenoid | Cranial bone that has a saddle-like depression, location of pituitary |
4. | Frontal bone | An unpaired cranial bone |
Which of the following diagrams describes a pivot joint?
1. | 2. | ||
2. | 4. |
Regarding the source of energy for muscle contraction:
I: | The immediate source is ATP |
II: | Creatine phosphate stores energy but has to be converted to ATP prior to use |
1. Only I is correct
2. Only II is correct
3. Both I and II are correct
4. Both I and II are incorrect
Column I | Column II | ||
A | Pivot joint | P | Between carpal and metacarpal of thumb |
B. | Saddle joint | Q | Between atlas and axis vertebrae |
C | Gliding joint | R | Between carpal bones |
D | Hinge joint | S | Humero-ulnar joint |
A | B | C | D | |
1. | P | Q | R | S |
2. | Q | P | S | R |
3. | Q | P | R | S |
4. | P | Q | S | R |
Assertion (A): | Vertebrochondral ribs are called true ribs. |
Reason (R): | Vertebraochondral ribs are attached to the thoracic vertebrae dorsally and are ventrally connected to the sternum. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | Both (A) and (R) are False. |