Which of the following changes occurs as the conducting tubes of the lungs become smaller?
A) Cartilage rings are gradually replaced by regular plates of cartilage.
B) Resistance to air flow decreases due to the increased number of tubes.
C) Smooth muscle amount increases.
D) Lining of the tubes changes from ciliated columnar to simple squamous epithelium which lines the alveoli.
Answer: C) Smooth muscle amount increases.
You might also like to view...
What phenomenon enables smooth muscle to maintain tension with comparatively less ATP consumption, as compared to skeletal muscle?
a. stretch phenomenon b. jump phenomenon c. piggy back phenomenon d. click phenomenon e. latch phenomenon
Keratinization softens cells
Indicate whether the statement is true or false.
Dietary control and weight reduction may be all that is necessary to completely reverse the symptoms in Type 2 diabetics
Indicate whether the statement is true or false
Describe the secretory method and functions of sebum
A) merocrine; sebum lubricates hair and skin, protects the keratin of the hair shaft, and inhibits bacterial growth B) holocrine; sebum lubricates hair and skin, protects the keratin of the hair shaft, and inhibits bacterial growth C) apocrine; sebum lubricates hair and skin, protects the keratin of the hair shaft, and inhibits bacterial growth D) merocrine; sebum is important in thermoregulation and excretion of wastes E) endocrine; sebum is important in thermoregulation and excretion of wastes