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:
If that were true, then the first thing that would happen when the sun disappeared is that Earth, along with all the other planets, would go flying off into space. It would be complete and utter chaos in our solar system. ... Therefore, we would still see the sun in our sky eight minutes after it was gone.
Hope this helps! :) )
Answer:
Frog forelimbs are typically short as the hind limbs are the principal limb pair generating propulsion.
Answer:
In grassland ecosystem, first trophic level is the producer. Producers are the organisms which makes their own food, here the producer are grasses. The second trohic level contain herbivores which feed on these grasses. These herbivores are eaten by secondary consumers which belongs to third trophic level and secondary consumers are then eaten by tertiary consumer.
The population of producers are very high so it is placed at the base while tertiary consumer are placed on the top due to low population.
Water is attracted to ions, such as sodium, potassium, phosphate, and chloride ions. Maintenance of normal intracellular fluid volume depends largely on the intracellular concentration of potassium and phosphate ions. Maintenance of extracellular water volume on the other hand depends primarily on the extracellular concentration of sodium and chloride ions.