50. Which type of muscles do the uterus, iris of the eye, and bronchi contain?
[SSC Selection Post (Matriculation), 20 June 2024, Shift 1]
(a) Smooth muscles
(b) Striated muscles
(c) Skeletal muscles
(d) Cardiac muscles
Answer: (a) Smooth muscles
Explanation: The uterus, iris and bronchi contain smooth muscle, whose actions generally occur without conscious control. Uterine contractions, changes in pupil diameter and bronchial calibre depend upon smooth-muscle activity. Cardiac muscle is confined to the heart and skeletal muscle moves bones.
49. The joint where the neck joins the head is:
[UPPSC PCS Prelims, General Studies Paper I, 2024]
(a) Saddle joint
(b) Hinge joint
(c) Pivotal joint
(d) Ball and socket joint
Answer: (c) Pivotal joint
Explanation: The expected examination answer is the pivot joint. More precisely, rotation of the head occurs at the atlanto-axial joint between the atlas and axis vertebrae. The neighbouring atlanto-occipital joint chiefly permits nodding and is anatomically a condylar joint.
48. In which part or organ of the human body is cartilage NOT found?
[UPSC NDA-II General Ability Test, 1 September 2024]
(a) Nose
(b) Trachea
(c) Bronchiole
(d) Knee joint
Answer: (c) Bronchiole
Explanation: Bronchioles lack cartilage in their walls and depend substantially on surrounding tissue and smooth muscle for support. Cartilage occurs in the nose, the C-shaped tracheal rings and the articular surfaces of the knee, where it reduces friction.
47. Which one among the following tissues helps to connect two bones?
[UPSC NDA-II General Ability Test, 1 September 2024]
(a) Tendons
(b) Ligaments
(c) Areolar tissue
(d) Cartilage
Answer: (b) Ligaments
Explanation: Ligaments are tough fibrous connective-tissue bands that join bone to bone and stabilize joints. Tendons join muscle to bone, while areolar tissue fills spaces and binds tissues. Articular cartilage provides a smooth, cushioning surface rather than acting as the primary bone-to-bone tie.
46. The axial skeleton is comprised of:
[Rajasthan CHO, 3 March 2024]
(a) Skull and vertebral column
(b) Vertebral column, ribs and sternum
(c) Skull, vertebral column, ribs and sternum
(d) Skull, vertebral column and ribs
Answer: (c) Skull, vertebral column, ribs and sternum
Explanation: The axial skeleton forms the central framework and includes the skull, vertebral column, ribs and sternum, together with associated hyoid and auditory ossicles. It supports posture and protects the brain, spinal cord and vital organs of the thorax.
45. Ribs are attached to which of the following structures?
[CGPSC Laboratory Assistant (Forensic Department), 25 August 2024, paper transcription]
(a) Scapula
(b) Clavicle
(c) Ilium
(d) Sternum
Answer: (d) Sternum
Explanation: Ribs articulate posteriorly with thoracic vertebrae, while anterior attachment to the sternum occurs through costal cartilage in the true ribs. The scapula belongs to the shoulder girdle, the clavicle to the collar region and the ilium to the pelvis.
44. Which one among the following diseases is caused due to deficiency of Vitamin D in humans?
[UPSC NDA-II General Ability Test, 1 September 2024]
(a) Beriberi
(b) Scurvy
(c) Rickets
(d) Pneumonia
Answer: (c) Rickets
Explanation: Vitamin D promotes intestinal absorption of calcium and phosphate required for mineralization of developing bone. Deficiency in children produces rickets, often with bowed legs or delayed growth; defective mineralization in adults is called osteomalacia.
43. Which among the following is a flat bone?
[SSC CHSL Tier I, 20 March 2023, Shift 1]
(a) Ankle bones
(b) Pelvic bones
(c) Wrist bones
(d) Ribs
Answer: (d) Ribs
Explanation: Ribs are flattened, curved bones that help form the protective thoracic cage. Their form supplies broad attachment areas for muscles and shields the heart and lungs. Wrist carpals and ankle tarsals are usually classified as short bones.
42. Which of the following is a type of connective tissue? I. Blood II. Bone III. Ligament
[SSC CHSL Tier I, 17 March 2023, Shift 2]
(a) Only III
(b) Only II and III
(c) I, II and III
(d) Only I and III
Answer: (c) I, II and III
Explanation: Blood is fluid connective tissue, bone is mineralized supportive connective tissue, and ligaments are dense fibrous connective tissue. Though their appearance varies greatly, all contain cells within a matrix and perform binding, support, defence or transport functions.
41. A sprinter feels cramps and pain in the thigh muscles after a run. This is due to accumulation of:
[UPSC CDS-I General Knowledge, 16 April 2023]
(a) Lactic acid
(b) Carbon dioxide
(c) Pyruvic acid
(d) Ethanol
Answer: (a) Lactic acid
Explanation: The conventional examination answer is lactic acid, produced during intense exercise when anaerobic glycolysis becomes prominent. Modern physiology notes that fatigue and cramping involve several mechanisms, so lactate itself should not be considered the sole direct cause of cramps.
