Differentiation in plants refers to the processes by which distinct cell types arise from precursor cells and become different from each other. Plants have about a dozen basic cell types that are required for everyday functioning and survival. Additional cell types are required for sexual reproduction. While the basic diversity of plant cell types is low compared to animals, these cells are strikingly different. For example, some cells such as parenchyma cells retain the potential to respond to environmental and/or hormonal signals throughout their life and, under the right conditions, can be transformed into another cell type (transdifferentiation). Other cells such as the water-conducting vessel elements undergo cell death as part of their differentiation pathway and thus can never transdifferentiate to another cell type
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Answer:
I'm pretty sure the answer is natural selection.
Explanation:
Natural selection acts on phenotypic variations in populations.
Answer:
The light from Alpha Centauri system takes 4.37 light-years and Sirius star system takes 8.6 light-years to reach the Earth.
Explanation:
Light from millions of stars in more distant galaxies takes a long time to reach the Earth. Light travels at a speed of 300,000 kilometers per second. The time taken for light from these stars to reach the Earth is the distance to the star divided by the speed of the light. The distance traveled by light in one year is known as a light year and the distance to the stars that are farther away is expressed in light years.
The Sun is the closest star to the Earth and the sunlight takes about 8.3 minutes to reach on Earth. Apart from the Sun, the other stars closest to Sun include Alpha Centauri system and the Sirius star systems.
The Alpha Centauri system includes the stars Alpha Centauri A, Alpha Centauri B and Proxima Centauri. This system is 4.37 light-years away from the Earth. The third star, Proxima Centauri is 4.24 light-years away from the Earth i.e., the light from it takes 4.24 years to reach the Earth.
The Sirius star systems include Sirius A (Dog Star) and Sirius B. It is about 8.6 light years from Earth and so the light about 8.6 years to reach the Earth.
The nurse should advise both the mother and the husband to spend equal time to each twin as this will strengthen the parental bonds to both twins and discourage favoritism since that is a common scenario in parents with twins.
The mother should also be encouraged to breastfeed both twins.
