Explain why genetic mutations don't always lead to cancer
What will be an ideal response?
Even though many body cells undergo mutations throughout a person's lifetime, most of these mutations do not result in malignancy for three reasons: (1) only a fraction of the mutations involve loss of control over the cell's growth and multiplication; (2) a cell usually becomes cancerous only after an accumulation of multiple independent mutations. This requirement contributes at least in part to the much higher incidence of cancer in older individuals, in whom mutations have had more time to accumulate in a single cell lineage; and (3) potentially cancerous cells that do arise are usually destroyed by the immune system early in their development.
You might also like to view...
The cervical sympathetic trunks:
A) are in the carotid sheaths. B) connect to cervical spinal nerves by gray and white communicating rami. C) emit cardiopulmonary splanchnic nerves. D) emit cranial splanchnic nerves. E) typically have ganglia associated with each spinal level.
What is the outcome of ketosis?
A) water retention and edema B) metabolic acidosis C) metabolic alkalosis D) glycogen buildup E) glucogenesis
The pectoral girdle, upper limb bones, pelvic girdle, and lower limb bones make up the
A) appendicular skeleton. B) axial skeleton. C) thoracic cage. D) vertebral column. E) pelvis.
Which of these blood values are in the normal range?
A. Venous PO2 = 100 mmHg B. Arterial PCO2 = 38 mmHg C. Venous PCO2 = 40 mmHg D. Arterial PO2 = 46 mmHg