Chapter 7, Problem 1TYR

Which cells have a ruffled border and secrete hydrochloric acid?

1. a. a C cells
2. b. osteocytes
3. c. osteogenic cells
4. d. osteoblasts
5. e. osteoclasts

Summary Introduction

Introduction:

Bones are present in vertebrates; it is rigid and protects various body organs. Bone tissue are of different types, including hard and dense connective tissue. The function of bone tissue is to support the body, protection, assisting movement, storage of minerals, production of blood cells, and storage of chemical energy and white blood cells. The intracellular matrix of the bone helps to maintain the blood calcium level in the body. The living bone takes up oxygen and release waste product during metabolism.

Answer to Problem 1TYR

Correct answer:

Osteoclast, bone-dissolving cells present on the surface of bones, have a ruffled border and secrete hydrochloric. Such cells with an increased surface area aids in bone resorption. Bone resorption is a process where the hydrated protein and minerals are digested by hydrochloric acid and collagenase. Therefore, option e is correct.

Explanation of Solution

Justify reasons for the correct statement:

Bone resorption is a process that takes place in ruffled border present on the apical side of osteoclast, which is divided into acid secretion and proteolysis. Hydrochloric acid secretion dissolves the bone minerals and degrade organic and inorganic matrix.

Option (e) is given as “osteoclast”.

Osteoclast is a large multinucleate bone with clear zone and ruffled border, which function bone resorption.

Hence, option (e) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as, “C cells”.

C cells are neuroendocrine cells present in thyroid secrete calcitonin. These cells are present adjacent to the thyroid follicles and connective tissue. Hence it is wrong answer.

Option (b) is given as, “osteocytes”.

Osteocytes are bone cells, which helps in maintaining the integrity of bone. Death of osteocytes causes osteoporosis. Hence it is wrong answer.

Option (c) is given as, “osteogenic”.

Osteogenic cells can divide, differentiate and develop to form a new bone called osteoblast. Osteoblasts in turn synthesis and secrete calcium salts and a collagen matrix and. Hence it is wrong answer.

Option (d) is given as, “osteoblast”.

Osteoblast contain single nucleus, which help in the process called bone formation. These cells arise from stem cell called mesenchymal cells, which also forms mycocytes and adipocytes. Hence it is wrong answer.

Hence option (a), (b), (c), and (d) are incorrect.

Conclusion

Osteoclast cells with a ruffled border acts as a mediator for resorption of bone tissue and release of minerals.