Which statement best describes cancer cells? . a. they grow as a single layer of cells.. b. they cease to reproduce after 20–50 mitotic divisions.. c. they reproduce only when needed to replace missing cells.. d. they are not regulated by contact inhibition..

The statement that best describes cancer cells is option D.

The correct answer is -

D) They are not regulated by contact inhibition.

Explanation:

Cancer cells are the rapidly proliferating cells that divide even without the presence of growth factors. They do not obey the property of contact inhibition (unlike normal cells, which stop dividing when they come in contact with each other).

In other words, cancer cells form disorganized multilayer of cells, which can not be regulated. As a consequence, they can even cross the blood vessels to other body organs ( a process that is called metastatis).

Thus, option D) is the best statement that describes cancer cells.

osteogenesis imperfecta (oi) refers to a congenital ailment of bones. in the condition, the bones become brittle or fragile. this ailment is a general result of the defect or mutations in the genes (colia1 or colia2). this mutation results in imperfect collagen formation either in quantity or quality wise.  

there are eight kinds of oi defects, and each kind varies with certain distinctions in symptoms. the usual symptoms include frequent bone fractures, loss of hearing in infants, protruding eyes, discoloration of the white in the eyes, respiratory issues, loosening of the joints, short stature, and other symptoms.