Answer:
C. "Because you have had one child with Tay-Sachs, you must each carry the allele. Any child you have has a 25% chance of having the disease
Explanation:
Tay-Sachs disease is an autosomal recessive disorder that means a child will acquire the phenotype or we can say disease only when both the alleles which cause disease are present in the child.
Here, in this condition neither parent has Tay-Sachs but they gave birth to a child who is suffering from the disease then it simply means that both the parents are carrier of this disease i.e. they both are heterozygous.
The cross and probability of healthy and diseased child is shown as under:
Mother Father
Parents Tt Tt
/ | | \
Off-springs TT Tt Tt tt
<u>Out of these 4 probable off-springs only 3 with genotype TT, Tt & Tt will be healthy while the 1 with genotype tt will be diseased.</u><u> </u><u>So, the probability of diseased child is 1/4 which is 25%. </u>
Also, the birth of children is an independent event so if one child has already been born with this disease then it doesn't mean that the next 3 children will be healthy for sure i.e. birth of first child cannot influence the next child. In short we can also say that in the next birth, there is still 25% chance of the child being born with this disease because previous birth has nothing to do with next birth.
Answer:
Sometimes referred to as DNA-DNA hybridization, this process hybridizes the genetic information from two different organisms to determine similarities between them. Scientists separate strands of DNA from both species using heat, which breaks the bonds between the base pairs that link the two sides of the double helix.
Explanation:
Lack of light and animals affect the rate of photosynthesis
Answer is A.
Archaea requires neither sunlight for photosynthesis as do plants, nor oxygen. Archaea absorbs CO2, N2, or H2S and gives off methane gas as a waste product the same way humans breathe in oxygen and breathe out carbon dioxide. An example is chemosynthetic bacteria by sea drifts. They use chemical energy to produce vital processes to live.
Answer:
The cytoplasm
Explanation:
Prokaryotic cells do not have nucleui so their DNA floats around in the cytoplasm.