In angiosperms, are sperm and eggs produced by mitosis or meiosis? Which cells are spores? Which structures are gametophytes?

Which statement below accurately describes the role of S-genes in plants?

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

Double fertilization means thata. flowers must be pollinated twice to yield fruits and seeds.b. every egg must receive two sperm to produce an embryo.c. one sperm is needed to fertilize the egg, and a second sperm is needed to fertilize the polar nuclei.d. every sperm has two nuclei.

In angiosperms, each pollen grain produces two sperm. What do these sperm do? a. Each one fertilizes a separate egg cell. b. One fertilizes an egg, and the other is kept in reserve. c. Both fertilize a single egg cell. d. One fertilizes an egg, and the other fertilizes a cell that develops into stored food.

Match questions 3–8 with options a–f. 3. Attracts pollinator 4. Develops into seed 5. Protects flower before it opens 6. Produces sperm 7. Produces pollen 8. Houses ovules a. pollen grain b. ovule c. anther d. ovary e. sepal f. petal

Some plant species produce male and female individuals in which the males have an XY genotype and the females have an XX genotype. After double fertilization, what would be the genotypes of the embryos and endosperm nuclei? (A) embryo XY/endosperm XXX or embryo XX/endosperm XXY (B) embryo XX/endosperm XX or embryo XY/endosperm XY (C) embryo XX/endosperm XXX or embryo XY/endosperm XYY (D) embryo XX/endosperm XXX or embryo XY/endosperm XXY

Some dioecious species have the XY genotype for male and XX for female. After double fertilization, what would be the genotypes of the embryos and endosperm nuclei?a. embryo XY/endosperm XXX or embryo XX/endosperm XXYb. embryo XX/endosperm XX or embryo XY/endosperm XYc. embryo XX/endosperm XXX or embryo XY/endosperm XYYd. embryo XX/endosperm XXX or embryo XY/endosperm XXY

In a species showing sporophytic incompatibility, which type(s) of pollen could successfully fertilize an S2S3 flower? (A) S1 pollen from an S1S3 flower (B) S2 or S3 pollen from an S2S3 flower (C) S3 pollen from an S1S1 flower (D) S1 pollen from an S1S1 flower