Learning through Art: Angiosperm Life Cycle Can you correctly identify important structures in the angiosperm life cycle? Drag each term to its proper place in the diagram.
T he Correct Answer and Explanation is :
Here’s the correct placement of key structures in the Angiosperm (flowering plant) life cycle diagram, followed by a detailed explanation.
Correct Answer Placement (Terms and Their Positions):
- Flower – At the start of the cycle where pollination occurs.
- Ovule – Inside the ovary, where the egg cell is housed.
- Anther – At the top of the stamen, produces pollen.
- Pollen grain – Produced by the anther, transferred to the stigma.
- Stigma – The receptive tip of the carpel where pollen lands.
- Pollen tube – Grows from the pollen grain through the style to the ovule.
- Sperm – Travels down the pollen tube to fertilize the egg.
- Egg – Located within the ovule, fuses with sperm to form a zygote.
- Zygote – Result of fertilization; develops into an embryo.
- Seed – Develops from the ovule after fertilization; contains the embryo.
- Fruit – Develops from the ovary; aids in seed dispersal.
- Seedling – Emerges from the germinating seed.
- Mature plant – Grows from the seedling; produces flowers to continue the cycle.
Explanation
The angiosperm life cycle is a classic example of alternation of generations, involving both diploid (sporophyte) and haploid (gametophyte) stages. The cycle begins with a mature flowering plant, the diploid sporophyte. This plant produces flowers, which are the reproductive structures. Inside the flower, the anthers (male part) produce pollen grains through meiosis, which are the male gametophytes.
Meanwhile, within the ovary of the flower’s carpel, the ovules form and contain the egg cell (female gametophyte). Pollination occurs when pollen is transferred to the stigma, usually by wind or pollinators. Once a pollen grain lands on the stigma, it germinates, forming a pollen tube that extends down the style into the ovule.
Two sperm cells travel down this tube. One fertilizes the egg, forming a zygote (which becomes the embryo), while the other fuses with two other nuclei in the ovule to form endosperm—a nutrient-rich tissue. This double fertilization is unique to angiosperms.
The fertilized ovule becomes a seed, which contains the embryo and food reserves. The surrounding ovary develops into a fruit, which helps in protecting the seeds and often aids in seed dispersal.
When conditions are right, the seed germinates, giving rise to a seedling. The seedling grows into a mature plant, completing the life cycle. This process ensures the propagation and survival of the species, highlighting the complexity and efficiency of angiosperm reproduction.
