Unit 06 · Flowers, Seeds & Fruit
This is the reproduction unit — and the year’s integration anchor. It covers flower structure, from the sepals and petals to the stamens (anther and filament) and the carpel (stigma, style, and ovary); how pollination and double fertilization turn an ovule into a seed and an ovary into a fruit; the alternation of generations behind it all; and the basics of Mendelian genetics — dominant and recessive traits and the 3:1 ratio Gregor Mendel counted out in his pea garden. Mastery means you can dissect a flower, trace its parts forward to seed and fruit, and predict the offspring of a cross.
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Flower structure | Thinks a flower is decoration, not a reproductive organ. | Names petals and sepals but confuses the stamen and carpel parts. | Identifies sepals, petals, stamens (anther and filament), and the carpel (stigma, style, ovary) and states each part’s role in reproduction. |
| Pollination & double fertilization | Cannot explain how pollen reaches an egg. | Describes pollination but not double fertilization or its two products. | Traces pollination through double fertilization to the seed embryo and the endosperm, and explains how the ovary becomes fruit. |
| Seed, fruit & alternation of generations | Thinks seeds and fruit are unrelated to the flower. | Connects flower to fruit but cannot place alternation of generations. | Explains how a fertilized ovule becomes a seed and the ovary a fruit, and locates the gametophyte and sporophyte in the life cycle. |
| Mendelian genetics | Cannot predict offspring from a simple cross. | Names dominant and recessive but sets up a Punnett square incorrectly. | Uses a Punnett square to predict a monohybrid cross, explains the 3:1 ratio, and reasons about dominant vs. recessive traits. |
| Lab technique (flower dissection) | Cannot open a flower without destroying its parts. | Dissects a flower but mislabels the reproductive structures. | Dissects a flower cleanly, identifies every whorl under the hand lens, and documents a pollination or seed-set observation. |
| Integration (cross-domain) | Treats the science as isolated facts; makes no cross-domain connection. | Names a link to history, reading, or writing but cannot defend why it matters. | Connects the unit to its anchor across History · Reading · Writing (plus chosen electives) and defends why the connection matters. |
“I opened the lily and found the stamens with their pollen-loaded anthers around the central carpel — stigma, style, ovary. After pollination, one sperm fertilizes the egg and the other makes the endosperm; that’s double fertilization. And for the pea cross, tall × short gave me the 3:1 ratio Mendel counted.”
“Flowers are just the pretty part of the plant. Pollen goes somewhere and then there’s a seed. I set up the pea square but I’m not sure how the ratio comes out.”
You demonstrate this unit through a flower dissection and a genetics cross — identifying every floral part under the hand lens and working a Punnett square aloud, not a multiple-choice test. A criterion counts as mastered only when you can both do the dissection and justify the plant biology behind it. Mastery is demonstrated, not awarded.
A 5-page clipboard packet — unit overview, key terms, the mastery rubric, anchor examples, and a score sheet you can print and grade against.