61% of emerging diseases is caused by zoonotic pathogens
Explanation:
Out of total emerging diseases zoonotic contributes 61%, that are originated from wildlife. The rate is increasing due to growth of human population, its mobility, frivolous, cultural and their socioeconomic purposes. Air is the major source for spread of infectious diseases. Zoonoses are generally caused by bacteria, viruses and pathogens that are blowout between animals and human beings. Modern zoonoses are Ebola virus and salmonella. One of such direct zoonoses is rabies, that is transformed directly from animal to human.
Heterozygous Red- Rr
Homozygous Red-- RR
Homozygous white-- rr
Monohybrid cross- Rr
Recessive allele- homozygous white i.e rr
Explanation:
Heterozygous have 2 different alleles of a gene as both Red and white alleles are present in the example Rr.
Homozygous: If the 2 alleles at a locus is same then they are homozygous, it can be dominant as RR or recessive as rr.
Recessive gene are the ones that can be masked by the dominant genes as red is dominant on white.
Monohybrid cross is the result of cross between the individual having either homologous dominant or recessive genes or genotype. The result is generally masking the recessive allele resulting in dominant phenotypic trait but the genotype changes.
From the example given in question:
A cross between dominant red as RR
and a cross between recessive white as rr
The punnet square shows:
r r
R Rr Rr
R Rr Rr
it can be seen that all progeny are red but genotype changed to heterozygous red as Rr
Answer:
The correct answer would be non-disjunction.
Down syndrome refers to the genetic disease caused by the non-disjunction of chromosome number 21.
Non-disjunction refers to the event in which the homologous chromosomes or sister chromatids fail to separate properly during a cell division.
In Down syndrome, the sister chromatids of chromosome 21 fail to separate properly which results in the formation of a gamete with 2 copies of chromosome 21.
When this gamete fertilizes with another gamete, it results in the formation of a zygote with 47 chromosomes, that is, 46 chromosomes + extra copy of chromosome 21.
E. coli are a species of bacteria. Like all bacteria, they have a round piece of DNA that contains most of their genetic information, but also plasmids, that contain some more. Plasmid can be passed on from bacterium to bacterium and they contain information for fighting antibiotics. Tetracycline is such an antibiotic. The process of putting a plasmid inside a bacterium is called transformation. So what the above sentence really says, is that a bacterium just got a plasmid that is probably holding the genetic information to produce proteins that fight antibiotics like tetracycline. While regular strains of E. coli might not be able to deal with tetracycline, transformed strains will probably be able to survive it. Hence, the culture will have live bacteria and the bacteria that have a plasmid against tetracycline will be favored and survive.
