Answer:
Explanation:
Selection is used in identifying some important traits for improving on or elimination.
Selection against is when a selection does not favour a particular allele. If recessive allele is selected against there will be a reduction in the frequency of the allele.
Since it was complete selection against the frequency of the allele will move from its level of fitness to zero and the allele of the gene will be lost completely in the genome of the organism.
natural selection i.e selection done by nature is not enough to get 100% selection against because of the allele reoccuring in heterozygous form but with artificial selection by man it is achievable.
Answer: B
Explanation: By most estimates, catalytic converters fitted inside the exhaust pipe of a gasoline-operated car convert over 90% of hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx) from the engine into less harmful carbon dioxide (CO2), nitrogen and water vapour.
Answer: Meiosis produces the sex cells, that is the gametes (sperm cells and eggs) that unite to form a zygote. Meiosis ensures that the gametes have have haploid chromosomes so that the resulting zygote from their fusion will have diploid chromosomes.
Explanation: Meiosis is a type of cell division in which a cell divides twice to produce four daughter cells each with the half the number of chromosomes as the parent cell. Without meiosis new gametes are not produced. Meiosis ensures that the chromosomes are evenly distributed among the daughter cells and that each daughter cell contains 23 chromosomes. A sperm cell with 23 chromosomes fuses with an egg with 23 chromosomes to form a zygote with 46 chromosomes. If meiosis does not occur, gametes with haploid chromosomes will not be produced, and if the gametes have diploid chromosomes because meiosis does not occur, sexual reproduction will be a disaster because when two diploid gametes fuse the resulting zygote with be abnormal.
