Structural Organisation In Animals Question 139

Question: Assertion : Bones possess longitudinal canals called lacunae. Reason : Lacunae carry blood vessels & nerves to the bones.

Options:

A) If both the assertion and the reason are true and the reason is a correct explanation of the assertion

B) If both the assertion and reason are true but the reason is not a correct explanation of the assertion

C) If the assertion is true but the reason is false

D) If both the assertion and reason are false

Show Answer

Answer:

Correct Answer: D

Solution:

Lacunae are actually the flat irregular spaces occurring in the solid matrix of bone.

Each lacuna lodges a flat bone cell or osteocyte.

Compact bone possesses many parallel, longitudinal column like structures called haversian systems, in which several concentric layers of bony matrix called lamellae encircle a longitudinal central canal called haversian canal.

It is the Haversian canal, which carries blood vessels and nerves to the bone.

Lacunae containing osteocytes occur in a layer between two lamellae.