A color-blind (X-linked recessive) human with Klinefelter syndrome has parents both of whom have normal color vision. 4a. From which parent did he receive his extra X chromosome? Explain

The extra X chromosome is received from mother.

Klinefelter's syndrome is the condition of chromosomal aberration where the person has an extra X chromosome. This means the genotype of the person is 44+XXY and the total chromosome number is 47. This condition is achieved due to inappropriate meiotic division and one of the sperm or ovum has the an extra X chromosome.

Here both the parents are normal in terms of colour vision. So the father cannot have the gene of colour blindness because if it was present, then father would have been colour blind because he has only one X chromosome per cell. So its present in mother who is heterozygous in terms of colour blind gene. So the extra X chromosome also came from her which made the presence of two defective X chromosomes in the offspring and made it colour blind.

a fossil fuel is a fuel formed by natural processes, such as anaerobic decomposition of buried dead organisms, containing energy originating in ancient photosynthesis.[1] the age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years.[2] fossil fuels contain high percentages of carbon and include petroleum, coal, and natural gas.[3] other commonly used derivatives include kerosene and propane. fossil fuels range from volatile materials with low carbon to hydrogen ratios like methane, to liquids like petroleum, to nonvolatile materials composed of almost pure carbon, like anthracite coal. methane can be found in hydrocarbon fields either alone, associated with oil, or in the form of methane clathrates.

the theory that fossil fuels formed from the fossilized remains of dead plants by exposure to heat and pressure in the earth's crust over millions of years was first introduced by andreas libavius "in his 1597 alchemia [alchymia]" and later by mikhail lomonosov "as early as 1757 and certainly by 1763".[4] the first use of the term "fossil fuel" was by the german chemist caspar neumann, in english translation in 1759.[5]

in 2017 the world's primary energy sources consisted of petroleum (34%), coal (28%), natural gas (23%), amounting to an 85% share for fossil fuels in primary energy consumption in the world.[6] non-fossil sources in 2006 included nuclear (8.5%), hydroelectric (6.3%), and others (geothermal, solar, tidal, wind, wood, waste) amounting to 0.9%.[7] world energy consumption was growing at about 2.3% per year. in 2015 about 18% of worldwide consumption was from renewable sources.[8]

the offspring would all be white. if the parents are both white flowers then they have the genotype rr, which when crossed results in an all white punnet square.