D3.2.5. Effects of dominant and recessive alleles on phenotype

Creeper in chickens is a condition in which the chickens are born with very short legs. The creeper allele (C) is dominant over the normal allele (c). Embryos which are homozygous for the dominant allele fail to develop into viable chickens and die before they hatch. What phenotypic ratio would you expect in the live offspring of a cross between two creeper chickens?

A. All creeper

B. 1 creeper; 2 normal

C. 2 creeper; 1 normal

D. 3 creeper; 1 normal

Creeper in chickens is a condition in which the chickens are born with very short legs. The creeper allele (C) is dominant over the normal allele (c). Embryos which are homozygous for the dominant allele fail to develop into viable chickens and die before they hatch. What phenotypic ratio would you expect in the live offspring of a cross between two creeper chickens?

A. All creeper

B. 1 creeper; 2 normal

C. 2 creeper; 1 normal

D. 3 creeper; 1 normal

Creeper in chickens is a condition in which the chickens are born with very short legs. The creeper allele (C) is dominant over the normal allele (c). Embryos which are homozygous for the dominant allele fail to develop into viable chickens and die before they hatch. What phenotypic ratio would you expect in the live offspring of a cross between two creeper chickens?

A. All creeper

B. 1 creeper; 2 normal

C. 2 creeper; 1 normal

D. 3 creeper; 1 normal

Creeper in chickens is a condition in which the chickens are born with very short legs. The creeper allele (C) is dominant over the normal allele (c). Embryos which are homozygous for the dominant allele fail to develop into viable chickens and die before they hatch. What phenotypic ratio would you expect in the live offspring of a cross between two creeper chickens?

A. All creeper

B. 1 creeper; 2 normal

C. 2 creeper; 1 normal

D. 3 creeper; 1 normal

The pedigree chart shows the inheritance of three generations of Duane syndrome, a condition caused by a dominant allele that affects alignment of the eyes.

_{[Source: Yang, M.-M., Ho, M. et al., 2013. Pedigree of a Chinese family with Duane retraction syndrome. [diagram online]
Available at: https://www.researchgate.net/figure/Pedigree-of-a-Chinese-family-with-Duane-retraction-syndrome-
Squares-men-circles_fig1_236921765 [Accessed 5 October 2021]. Public domain.]}

If individuals II:1 and II:2 had a third child, what is the probability that the child would have Duane syndrome?

A.  25 %

B.  50 %

C.  75 %

D.  100 %

The pedigree chart shows the inheritance of three generations of Duane syndrome, a condition caused by a dominant allele that affects alignment of the eyes.

_{[Source: Yang, M.-M., Ho, M. et al., 2013. Pedigree of a Chinese family with Duane retraction syndrome. [diagram online]
Available at: https://www.researchgate.net/figure/Pedigree-of-a-Chinese-family-with-Duane-retraction-syndrome-
Squares-men-circles_fig1_236921765 [Accessed 5 October 2021]. Public domain.]}

If individuals II:1 and II:2 had a third child, what is the probability that the child would have Duane syndrome?

A.  25 %

B.  50 %

C.  75 %

D.  100 %

The pedigree chart shows the inheritance of three generations of Duane syndrome, a condition caused by a dominant allele that affects alignment of the eyes.

_{[Source: Yang, M.-M., Ho, M. et al., 2013. Pedigree of a Chinese family with Duane retraction syndrome. [diagram online]
Available at: https://www.researchgate.net/figure/Pedigree-of-a-Chinese-family-with-Duane-retraction-syndrome-
Squares-men-circles_fig1_236921765 [Accessed 5 October 2021]. Public domain.]}

If individuals II:1 and II:2 had a third child, what is the probability that the child would have Duane syndrome?

A.  25 %

B.  50 %

C.  75 %

D.  100 %

The pedigree chart shows the inheritance of three generations of Duane syndrome, a condition caused by a dominant allele that affects alignment of the eyes.

_{[Source: Yang, M.-M., Ho, M. et al., 2013. Pedigree of a Chinese family with Duane retraction syndrome. [diagram online]
Available at: https://www.researchgate.net/figure/Pedigree-of-a-Chinese-family-with-Duane-retraction-syndrome-
Squares-men-circles_fig1_236921765 [Accessed 5 October 2021]. Public domain.]}

If individuals II:1 and II:2 had a third child, what is the probability that the child would have Duane syndrome?

A.  25 %

B.  50 %

C.  75 %

D.  100 %

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Deduce reasons for the difference between the results of Cross 2 and Cross 3.

Identify, using one recognition feature visible in the photo, the phylum in which D. plantarius is classified.

Identify, using one recognition feature visible in the photo, the phylum in which D. plantarius is classified.

Identify, using one recognition feature visible in the photo, the phylum in which D. plantarius is classified.

Identify, using one recognition feature visible in the photo, the phylum in which D. plantarius is classified.

Identify, using one recognition feature visible in the photo, the phylum in which D. plantarius is classified.

Identify, using one recognition feature visible in the photo, the phylum in which D. plantarius is classified.