Answer:
E. They decrease the rate at which Ras hydrolyzes GTP.
Explanation:
Activated Ras has GTP bound to it, this propagates an intracellular signal to the nucleus where cell proliferation is induced. Thereafter proliferation is switched off by the hydrolysis of the bound GTP to GDP.
Therefore decreasing the rate of GTP hydrolysis causes Ras to remain active, ultimately leading to uncontrollable proliferation characteristic of cancer.
Answer:
The two circuits of the cardiovascular system are: Pulmonary Circuit and Systematic Circuit. The pulmonary circuit is shorter than the systemic and is responsible for carrying deoxygenated blood to the lungs from the right atrium, for oxygenation. The systemic circuit is longer and leaves the aortic artery, carrying oxygenated blood throughout the body and nutrients for survival. If less blood were pumped into the systemic circuit, this amount would not be sufficient to compensate for the organism's needs, with the corresponding consequences that this would entail.
It is said that the cardiovascular system is a closed system because blood travels inside a network of blood vessels without leaving them.
Answer:
A
Explanation:
It allows the cell to control what materials enter and leave.
D. Learned behaviors do not directly affect natural selection because they are not inherited.
This is true because learned behaviors can be taught to the offspring but do not come within them the way instincts do.
