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The sporophyte generation begins when ______.  

Which of the following flower parts is specialized to receive pollen?  

The most abundant cells in plants (found in the flesh of fruit, the outer surface of young plants, and the photosynthetic cells) are the ______.  

What is the function of the guard cells?  

Epistasis is:

Phenylketonuria (PKU) is an autosomal recessive condition where R is normal and r is the PKU mutation.  Two parents, who are both heterozygous, have five children. (Recall: a carrier is heterozygote) a. What is the probability of a child being born with PKU? (enter answer in first box) b. What is the probability the five children are born in this specific order: affected with PKU, carrier for PKU, carrier for PKU, affected with PKU, homozygous dominant? (enter answer in second box) c. What is the probability that one of the children is either homozygous dominant or homozygous recessive? (enter answer in third box) d. What is the probability that out of 5 children, 1 child is born with PKU? (enter answer in fourth box)

Sickle-cell disease in humans is an example of

Albinism is an autosomal recessive condition. Consider the cross Aa x Aa. Calculate the following probabilities: a. A carrier offspring or an offspring with albinism. (answer in first box) b. Two offsprings in a row with albinism. (answer in second box)

Color-blindness is a recessive X-linked condition.  XA is the allele for normal vision and Xa is the allele for color blindness.  Consider the cross between a female who is heterozygous for color blindness and a male who is color blind. a. What is the genotype of the female? (answer in first box) b. What is the genotype of male? (answer in second box) Calculate the following probabilities (out of all offsprings): c. Color-blind daughter (answer in third box) d. Color-blind son (answer in fourth box) e. Son with normal vision (answer in fifth box) f. Daughter with normal vision (answer in sixth box)

When comparing Prophase I of meiosis with Prophase of mitosis, which of the following occurs only in meiosis?