Animal cells each have a centrosome and lysosomes, whereas plant cells do not
Answer and Explanation:
During the whole biota history, there occurred extinctions due to different reasons.
During the Cretaceous, which took place between 145-65 million years ago, there occurred a massive extinction that eliminated most of the species on the Earth. Many of the characteristic groups of this period were affected. Dinosaurs, Plesiosaurs, Ammonites, Tricodonts, Cycas, Gynkgos, Conifers, the recent angiosperms, birds, and mammals.
The extinction was caused by the volcanic eruptions, and the unusual fall of many different asteroids, which caused important changes on the Earth´s surface. The consequent climatic change was what ended affecting all the species directly. The extinction was gradual, although it occurred in a short geological lapse of time.
Answer:
How long is the G2 phase = 6hours
Explanation:
Cell cycle undergoes various stages during mitotic cell division.
Normally cells are arrested in the resting phase G0 but as the cell division starts it undergoes G1 the growth phase then it undergoes S phase called the Synthesis phase in which the DNA synthesis occurs. Then it undergoes G2 Phase and is the shortest phase while G1 is the longest phase of the cycle. G2 normally lasts for 3-4 hours so here it may take 2.775 hours as due to presence of Thymidine the synthesis of DNA occur at high level so it contains higher levels of cellular DNA than in the G1 . so it will take 6hours G2 phase to occur.
Answer: The role of substance A in photosynthesis is: it combines with water to form glucose.
Explanation:
I believe the correct answer is homeostasis.
