Answer:
During depolarization, the membrane potential rapidly shifts from negative to positive. As the sodium ions rush back into the cell, they add positive charge to the cell interior, and change the membrane potential from negative to positive.
Explanation:
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:
Earliest- gametophyte dominance, sporophyte dependence
Middle- sporophyte dominance, gametophyte independence
Recent- sporophyte dominance, gametophyte dependence
Explanation:
The life cycle of plant alternates between the two phases: the haploid gametophyte which produces gametes and the diploid sporophyte which produces spores. The evolution of land plants shows how these are dependent on each other in terms of the requirement of nutrition.
In bryophytes, the gametophyte is the dominant phase on which the sporophyte depended. Later in pteridophytes, the sporophyte became dominant which is present in the later evolved groups namely the gymnosperms and the angiosperms. The gametophyte was independent on the sporophyte but in angiosperms and gymnosperms, it is dependent.
Carbon forms the key component for all known life on Earth. Carbon is the basis of all molecules. Its is easily able to bond because of the 4 valence electrons.
