Answer:
See explanation below
Explanation:
<em>Non-disjunction occur as a result of lack of separation of homologous chromosomes during meiosis. </em>
As a result, the gametes (the daughter cells formed) produced end up having extra or lesser chromosomes as compared to a normal gamete.
When a gamete with extra chromosome fertilizes a normal gamete, the resulting offspring will have an extra chromosome (trisomy condition).
On the other hand, when a gamete with one less chromosome than normal fertilizes a normal gamete, the resulting offspring will have one less chromosome than normal offspring (monosomy condition).
Assuming a chromosome with Aa gene undergoes non disjunction during meiosis, the resulting gametes either contain both A and a chromosome or contain no chromosome at all.
If Aa gamete is fertilized by a normal haploid sperm (a), the resulting zygote will have the genotype Aaa.
If a gamete with no chromosome at all fertilizes a normal haploid sperm, the resulting offspring will have the genotype a.
Answer:
DNA sequences.
Explanation:
DNA sequences, I believe, are the best evidence of common ancestry since they share more traits with more closely related organisms. The similarities and variances in fossils, anatomy, and embryos are all due to DNA.
Answer:
- It improves the growth of crops.
- It harms organisms that live in the oceans.
Explanation:
Fertilizers provide nutrients to plants, where the most needed nutrients in agriculture are nitrogen, phosphorus and potassium. Negative media coverage of the role of agriculture in pollution can make farmers feel guilty about the use of fertilizers. However, reducing fertilizer input can slow plant growth and exacerbate problems such as soil erosion. While it is important to be aware of the effects of fertilizers and use them with caution, it is also important for everyone to recognize that agricultural fertilizers are not the main source of pollution. If the plant uses all the nutrients and uses fertilizer wisely to prevent leaching, there is little chance of contamination.
Nitrate leaching from the soil poses a serious health risk and can contribute to soil acidification. When high levels of nitrogen are used, or when clover grass meadows fix significant nitrogen, nitrates inevitably seep out into groundwater where the water table is present, especially in sandy or well-drained soils. There is a possibility of entering. When this groundwater is used for domestic supply, leaching poses a serious health risk.
The fertility rate of 2.1 with which populations are expected to eventually stabilize is known as the long-term replacement rate. In other words, if a nation maintains a fertility rate of 2.1 over a long period of time the population of that nation will eventually stabilize and it will neither grow nor shrink. Immigration allows the people to grow faster than the fertility rate would suggest. Also because of past growth, the population is younger than it would otherwise be. This means that there are more potential mothers and fathers. Only after its residents age can the population of a country stabilize.
