Answer:
Identify how the physical barriers of the immune system protect the body against pathogens?
skin contains tightly packed cells
•skin is tough, flexible, and waterproof
Explanation:
Answer:
Cancer is basically a disease of uncontrolled cell division. Its development and progression are usually linked to a series of changes in the activity of cell cycle regulators. For example, inhibitors of the cell cycle keep cells from dividing when conditions aren’t right, so too little activity of these inhibitors can promote cancer. Similarly, positive regulators of cell division can lead to cancer if they are too active. In most cases, these changes in activity are due to mutations in the genes that encode cell cycle regulator proteins.
Explanation:
Answer:
1. 1.00(1/2)^151/30.2= 31.3 g
2. 24g-->1.4 g = 4 half-lives, so 4*5730= 22920 years
3. 64g-->2.0g = 5 half-lives, so 12.5/5= 2.5 hours