Fill in the blanks in the diagram about double fertilization in flowering plants.

Schema of double fertilization in flowering plants

Instructions: Fill in the empty spaces in the diagram.

The diagram shows the process of double fertilization in flowering plants. It starts with a 'Flower' which leads to the 'Pistil'. Within the pistil is the 'Embryo sac of the ovary'.

• From the 'Flower', pollen is produced, leading to the 'Pollen grain'.
• The 'Pistil' contains the 'Embryo sac of the ovary', which in turn contains the 'Egg cell' and another nucleus.
• The 'Pollen grain' develops into two sperm cells: the 'First sperm' and the 'Second sperm'.
• The 'First sperm' fuses with the 'Egg cell' to form the 'Zygote', which develops into the 'Embryo'.
• The 'Second sperm' fuses with another nucleus (likely the polar nuclei) in the embryo sac to form the 'Endosperm', which serves as nutritive tissue.

Therefore, the completed diagram should show the following connections and labels:

• Flower leads to Pistil and Pollen grain.
• Pistil leads to Embryo sac of the ovary.
• Pollen grain leads to First sperm and Second sperm.
• Embryo sac of the ovary leads to Egg cell and another nucleus (which fuses with the second sperm).
• Egg cell combines with the First sperm to form the developing Embryo.
• The Second sperm combines with another nucleus to form the Endosperm.

Filled Diagram Structure:

• Top: Flower
• Branching from Flower: Pollen grain and Pistil
• From Pistil: Embryo sac of the ovary
• From Pollen grain: First sperm and Second sperm
• From Embryo sac of the ovary: Egg cell and a blank box (for polar nuclei)
• First sperm + Egg cell leads to: Embryo
• Second sperm + (polar nuclei) leads to: Endosperm