Each follicle contains a tiny hair and multilobed sebaceous glands.
Sebaceous glands get their name from the oily substance they produce - sebum .
Under normal circumstances, sebum travels up the hair follicle and out to the skin's surface. However, in acne, sebum is trapped within the follicle. Red, swollen, pus-filled lesions are called papules , nodules , and pustules . Bacteria Each of these factors is discussed in more detail below. Acne usually begins when the body starts to produce the hormones called androgens.