Gently separate the tip of the hypocotyl from the cotyledon with the dissecting needle. Be careful not to break off the tip. Note that the hypocotyl is embedded in the cotyledon. a.What parts of the plant develop from the hypocotyl? _____________________________________________________________________ 11.
Examine the cotyledon. Notice how its broad surface is firmly attached to the endosperm. 12.Sketch the cut surface of the corn grain in the box. Label the ovary wall, endosperm, cotyledon, epicotyl, plumule, hypocotyl, and radicle. Part II – Eudicot Seed The bean seed is a eudicot seed – it contains two cotyledons. Bean seeds are produced in a pod (the fruit of the bean plant). Each seed is covered by a hard, protective seed coat, known as the testa, and is attached to the pod at the hilum. At one end of the hilum is a small pore called the micropyle. This pore is where the pollen tube entered the ovule of the flower. The micropyle is the only place where water can enter the seed. 1.Examine the soaked lima bean seed. Locate the hilum – a scar on one side of the seed. 2.Use the hand lens to examine the micropylea.Does the micropyle seem to extend all the way through the seed coat? b._____________________________________________________________________ 3.Sketch the bean seed in the box. Label the hilum, seed coat, and micropyle4.Peel the seed coat from the seed very carefully. Near the hilum and micropyle a part of the inner seed may break easily. Try not to break it off. If the two halves of the seed seem to be coming apart, hold them together. Place the inner seed on a paper towel. . .