If a pollen grain fails to generate two sperm cells, what is the most likely result of pollination?

Question

A.  Half the seeds would develop fine, but the other half would die.
B.  The resulting progeny would be haploid.
C.  The seeds would lack either embryos or endosperm, and so would be nonviable.
D.  The endosperm would be smaller.

Clarify Question
What is the key concept addressed by the question?
What type of thinking is required?

Gather Content
What do you already know about plant gametes and fertilization? What other information is related to the question?

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?

Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
 

Answer 1

C.  The seeds would lack either embryos or endosperm, and so would be nonviable.

Clarify Question
What is the key concept addressed by the question?
        · This question is asking about the effect of missing sperm in a pollen grain.
What type of thinking is required?
        · Analyze level:
            o This is an analyze question because you have to break the function of sperm in a pollen grain and their role in the development of a plant embryo into their component pieces to understand how they function.

Gather Content
What do you already know about plant gametes and fertilization? What other information is related to the question?
        · Two sperm cells are normally carried in a pollen grain.
        · One of the two sperm cells fuses with two polar nuclei in the embryo sac of a plant seed to form the endosperm.
        · The endosperm is the food supply of an embryo.
        · The other sperm cell from the pollen grain fuses with the egg cell, which forms a zygote.

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?
        · The endosperm cannot form without a sperm cell from the pollen grain, and without the endosperm, the embryo would not have a food source. Additionally, the zygote will not form without a sperm cell from the pollen grain. If the pollen grain was missing one of the two necessary sperm cells, the plant embryo could not grow.

Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        · Analyze level:
            o Answering this question correctly depended not only on distinguishing between the necessary number of sperm in a pollen grain and the role of those sperm in embryo development, but on your ability to break down, or analyze, the consequences of a lack of sufficient sperm cells in the pollen grain. If you got an incorrect answer, did you remember that the functions of the sperm in the pollen grain include fertilizing the egg as well as facilitating the formation of the endosperm as a food source for the embryo? Did you have trouble breaking down the role of sperm cells in embryo development to determine the correct answer?