Answer:
D. Cyclin
Explanation:
Cyclins drive the events of the cell cycle by partnering with a family of enzymes called the cyclin-dependent kinases (Cdks). A lone Cdk is inactive, but the binding of a cyclin activates it, making it a functional enzyme and allowing it to modify target proteins.
Answer: dinosaurs and birds
Plentiful collection of f<span>ossils of early birds and their most immediate predecessors has settled the century-old controversy about the origin of birds. Birds are now safely declared to evolve from a group of dinosaurs known as maniraptoran theropods. Birds have similar shape of the bones as a variety of maniraptorans have. A host of fossils have shown also that the maniraptorans lay looked alike eggs as that of birds and they resemble the birds in the way they laid their eggs also. Those reasons prove that they are most closely related.</span><span>
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Answer:
Use the rule that 10% of the energy is transferred between layers.
Explanation:
Energy is transferred between layers of a food pyramid. That means that the producers at the bottom of the pyramid (e.g. green plants) provide energy to the primary consumers (e.g. rabbits), which are eaten by and provide energy to the secondary consumers (e.g. foxes).
However, very little of the energy is actually transferred to the next layer, roughly 10%. So an easy way to calculate the energy available at each level is to calculate 10% of what was available from the previous level. So if there is 600 kJ available from the primary consumers, then 60 kJ are transferred to the secondary consumers
Answer:
Cancer is unchecked cell growth. Mutations in genes can cause cancer by accelerating cell division rates or inhibiting normal controls on the system, such as cell cycle arrest or programmed cell death. As a mass of cancerous cells grows, it can develop into a tumor.
Explanation:
The pollen grain is actually the male gametophyte generation of seed plants. Inside the anther, pollen mother cells divide by meiosis to form pollen grains whose nuclei contain half the number of chromosomes characteristic of the parent plant.
(hope that helped answer the question)
