Evaluate these statements about double fertilization. Select True or False for each sentence. T/F Two zygotes are formed, but only one survives. T/F One sperm fuses with an egg while the other sperm fuses with polar nuclei. T/F It results in the formation of a diploid embryo and triploid endosperm. T/F Both sperm involved in double fertilization form within the same pollen tube.

Verified step by step guidance

1. Step 1: Let's evaluate each statement one by one. The first statement is 'Two zygotes are formed, but only one survives.' This is False. In double fertilization, only one zygote is formed.
2. Step 2: The second statement is 'One sperm fuses with an egg while the other sperm fuses with polar nuclei.' This is True. In double fertilization, one sperm cell fertilizes the egg cell to form a zygote, while the other sperm cell fertilizes the two polar nuclei to form the endosperm.
3. Step 3: The third statement is 'It results in the formation of a diploid embryo and triploid endosperm.' This is True. The zygote develops into a diploid embryo, and the fertilized polar nuclei develop into a triploid endosperm, which provides nutrients to the developing embryo.
4. Step 4: The last statement is 'Both sperm involved in double fertilization form within the same pollen tube.' This is True. The two sperm cells involved in double fertilization are produced by the same pollen grain and travel down the same pollen tube to reach the ovule.
5. Step 5: So, the correct answers are: False, True, True, True.

Key Concepts

Double Fertilization

Double fertilization is a unique process in angiosperms (flowering plants) where two sperm cells from a pollen grain fertilize different cells in the ovule. One sperm cell fuses with the egg cell to form a diploid zygote, while the other sperm fuses with two polar nuclei to form a triploid cell, which develops into the endosperm, providing nourishment to the developing embryo.

Zygote and Endosperm Formation

In double fertilization, the formation of the zygote and endosperm is crucial. The zygote, which is diploid, will develop into the embryo of the seed, while the triploid endosperm serves as a food reserve for the embryo, ensuring its growth and development until it can photosynthesize independently.

Pollen Tube Function

The pollen tube is a structure that forms after a pollen grain lands on a compatible stigma. It grows down the style to deliver sperm cells to the ovule. In double fertilization, both sperm cells travel through the same pollen tube, allowing them to reach the ovule simultaneously to participate in the fertilization process.