Helped to confirm that environmental changes cannot affect the characteristics of a species.
NACL is the correct answer
Most hydroelectric power plants have a dam and a reservoir. These structures may obstruct fish migration and affect their populations. Operating a hydroelectric power plant may also change the water temperature and the river's flow. These changes may harm native plants and animals in the river and on land. Reservoirs may cover people's homes, important natural areas, agricultural land, and archaeological sites. So building dams can require relocating people. Methane, a strong greenhouse gas, may also form in some reservoirs and be emitted to the atmosphere. Reservoir construction is "drying up" in the United States Gosh, hydroelectric power sounds great -- so why don't we use it to produce all of our power? Mainly because you need lots of water and a lot of land where you can build a dam and reservoir, which all takes a LOT of money, time, and construction. In fact, most of the good spots to locate hydro plants have already been taken. In the early part of the century hydroelectric plants supplied a bit less than one-half of the nation's power, but the number is down to about 10 percent today. The trend for the future will probably be to build small-scale hydro plants that can generate electricity for a single community. As this chart shows, the construction of surface reservoirs has slowed considerably in recent years. In the middle of the 20th Century, when urbanization was occurring at a rapid rate, many reservoirs were constructed to serve peoples' rising demand for water and power. Since Hydroelectric energy is produced by the force of falling water. The capacity to produce this energy is dependent on both the available flow and the height from which it falls. Building up behind a high dam, water accumulates potential energy. This is transformed into mechanical energy when the water rushes down the sluice and strikes the rotary blades of turbine. The turbine's rotation spins electromagnets which generate current in stationary coils of wire. Finally, the current is put through a transformer where the voltage is increased for long distance transmission over power lines.
Hydroelectric-power production in the United States and the world!
(sorry this is the second part)
Part 1.
The correct answer is option 2.There are two alleles for freckles.
According to the condition of the occurrence of the freckles, it can be concluded that the freckle is an autosomal dominant condition. The freckle can only be inherited, if there is at least one dominant allele in any of the parent. If both the individuals are heterozygous for the trait, they can produce an offspring without freckle by passing down the recessive alleles to the progeny. So, the freckles are controlled by two alleles, which can be either dominant or recessive.
Part 2.
The correct answer is option 4. P generation and F2 generation.
In this case, it is given that true bred homozygous recessive plant is crossed with true bred homozygous dominant plant. The true bred recessive plant always shows the recessive phenotype. When true bred homozygous recessive plant is crossed with true bred homozygous dominant plant, the F1 generation would produce all the heterozygous individual and exhibit dominant phenotype. When the F1 generation is self crossed, it result in 75% dominant phenotype and 25% recessive phenotype.
A possible cross for this case is given in the picture.
1/4 assuming that red eyes are recessive.
