Answer:
True
Explanation:
Truly, the typical X shaped chromosomes is the result of DNA replication. When the DNA has replicated, it then condenses and coil into the X-shaped of the chromosome. This then implies that replicated chromosomes take the X-shaped structures seen under a microscope.
When this replication occurs, the chromosome is made of two structures that are identical. They are known as the sister chromatids. These chromatids are actually joined at the centromere.
Answer:
A. The results are close to a 1:1 ratio of plants with red flowers to plants with white flowers. Therefore, the genotypes of the parents are Rr and rr.
Explanation:
I took the test and got it right.
Answer: The given statement is true.
Explanation: Ionization energy is defined as the amount of energy required to remove an electron from the outermost shell of an isolated gaseous atom.
General equation of ionization energy is given by:
- If the outermost electron is loosely bound to the nucleus which means that the electron can be easily removed form an atom, it will require less amount of ionization energy.
- And if the outermost electron is tightly bound to the nucleus which means that the electron cannot be removed easily from an atom. And hence, it will require more ionization energy.
Hence, the given statement is true.
<span>Damming a river has a variety of effects on the freshwater ecosystem, more than just altering the flow from A to B. Dams create calm bodies of water, changing overall temperature regimes and sediment transport, leading to conditions which tend to favour generalist species. Loss of specialist species, particularly endemics, changes the community structure and leads to biotic homogenization. A dam will withhold sediment in the reservoir, not just decreasing the amount of substrate available to local freshwater species, but even impacting diadromous, estuarine and marine species much further downstream. The competition between resident species for food and breeding sites will increase as damming isolates populations, and perhaps more importantly, damming completely restricts migratory fish species. Isolation may lead to decreases in genetic diversity and therefore puts species at greater risk from disease. All of these effects may be exacerbated by changes in the surrounding land use. Overall, damming river flow will lead to both a loss of native species, but also an increase in exotic species which are more likely to become established in degraded habitats. For this reason, dams are one of the greatest global threats to freshwater biodiversity.</span>
