Question

Growth factors are local regulators that

(A) are produced by the anterior pituitary.

(B) are modified fatty acids that stimulate bone and cartilage growth.

(C) are found on the surface of cancer cells and stimulate abnormal cell division.

(D) bind to cell-surface receptors and stimulate the growth and development of target cells.

Short answer

(A) The statement “is produced by the anterior pituitary” is false.

(B) The statement “are modified fatty acids that stimulate bone and cartilage growth” is false.

(C) The statement “is found on the surface of cancer cells and stimulate abnormal cell division” is false.

(D) The statement “bind to cell-surface receptors and stimulate growth and development of target cells” is true.

Step-by-step solution

Growth factors

The biologically active molecules secreted by the pituitary gland necessary for enhancing cell proliferation and wound healing are called growth factors.

Explanation of option ‘(A)’

The anterior pituitary represents the front part of the body’s pituitary gland and is essential for synthesizing and releasing hormones.

Thus, other than the anterior pituitary, growth factors are also synthesized by cartilage and blood cells.

Therefore, the given statement is false.

Explanation of option ‘(B)’

The flexible connective tissue present in joints between the bones that provides shape and support to body tissue is called cartilage.

Thus, the growth factors are composed of polypeptides rather being modified fatty acids.

Therefore, the given statement is false.

Explanation of option ‘(C)’

When a cell duplicates and splits its chromosomal content to form daughter cells through a process, it is called cell division.

Thus, the abnormal division of cancer cells occurs due to a genetic mutation.

Therefore, the given statement is false.

Explanation of option ‘(D)’

The significance of growth factors are stimulating cell division, cell migration, apoptosis, and wound healing.

Thus, the growth factors stimulate cell growth and multiplication by attaching to the cell’s binding site.

Therefore, the given statement is true.