Chitin is also found in the cell walls of fungi.
The exoskeleton of Arthropods is made up of Chitin.
(A) Hyaluronic Acid - Incorrect: This is a component of animal connective tissue, not exoskeletons.
(B) Chitin - Correct: Arthropod exoskeletons consist of chitin, a nitrogen-containing polysaccharide.
(C) Waxes - Incorrect: While waxes may coat the exoskeleton, they're not its structural component.
(D) Cellulose - Incorrect: This is the plant cell wall component, not found in arthropods.
The correct answer is (B) Chitin, the characteristic tough polysaccharide in arthropod cuticles.
The exoskeleton of arthropods (such as insects, crustaceans, and arachnids) is primarily made of chitin, a complex polysaccharide. Chitin is tough, flexible, and provides both strength and rigidity to the exoskeleton.
Other options:
Option (B) is correct as chitin forms the exoskeleton of arthropods.
Match the following:
List - I | List - II | ||
---|---|---|---|
A) | Thyroid gland | I) | Calcitonin |
B) | Adrenal medulla | II) | Nor epinephrine |
C) | Pineal gland | III) | Melatonin |
D) | Pancreas | IV) | Glucagon |
Study the following and pick up the correct combinations:
S.No. | Spinal nerves | No. of pairs in man | Location |
---|---|---|---|
I | Cervical nerves | 7 pairs | Neck region |
II | Thoracic nerves | 12 pairs | Thorax |
III | Sacral nerves | 5 pairs | Lumbar region |
IV | Coccygeal nerves | 1 pair | Caudal region |
Match the following:
List - I | List - II | ||
---|---|---|---|
A) | Radius, ulna | I) | Fore limb |
B) | Tibia, fibula | II) | Hind limb |
C) | Scapula, clavicle | III) | Pectoral girdle |
D) | Ilium, pubis | IV) | Pelvic girdle |