Answer:
Ss (male) × Ss (female)
Explanation:
This question involves a single gene coding for hair length in guinea pigs. Based on the information in this question, the allele for short hair (S) is dominant over the allele for long hair (s). This means that a guinea pig will only be phenotypically long-haired if the genotype is "ss".
According to this question, Two short-haired guinea pigs are mated several times. Out of the 100 offsprings produced by this cross, 25 of them have long hair (recessive). This means that the phenotypic ratio of this cross is 3 short hair : 1 long hair i.e. 100 - 25 = 75 short hair. 75/25 = 3/1 = 3:1
To produce this phenotypic ratio, the parents must both be heterozygous (Ss) for the hair length gene.
<h2><u>Answer</u> :</h2>
The correct option is A. If a dominant allele is present, the recessive allele won’t be seen.
The dominant allele is the one which appear, and the recessive one isn't shown.
For example - If a person has 2 alleles of eye colour as B ( black ) and b ( brown ), in which black is dominant and the brown one is recessive, then the person will have black eye colour because only dominant allele shows its characteristics.
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Answer: The clinician should EXAMINE THE CHILD FOR SYMPTOMS OF HEMOPHILIA A.
Hemophilia A is an X-linked inherited disease that causes stiffness in the joints of infants. Infants also refuse to walk due to pain and joint stiffness. Headache, weakness, abdominal pain, stiff neck, etc are few other symptoms of this disease.