Biology Plant Reproduction and Structure Flashcards

Which tissue in a plant seed stores nutrients to support early embryo growth?

Answer: Endosperm

Endosperm is the nutrient-rich tissue in seeds that provides food for the developing embryo before photosynthesis can begin.

In angiosperms, double fertilization produces which two structures?

Answer: Zygote and endosperm nucleus

Double fertilization in angiosperms produces a diploid zygote (2n) and a triploid endosperm nucleus (3n).

What is the function of the micropyle in a seed?

Answer: Allows water and oxygen entry for germination

The micropyle is a small pore in the seed coat through which water and gases enter to initiate germination.

Which of the following is a characteristic unique to monocot seeds compared to dicot seeds?

Answer: One cotyledon

Monocots have a single cotyledon (seed leaf), while dicots have two cotyledons, which is the defining structural difference.

Seed dormancy is MOST directly broken in many species by:

Answer: Prolonged cold treatment (stratification)

Stratification, exposure to cold and moist conditions over time, breaks dormancy in many temperate species by reducing ABA levels.

Which plant hormone is primarily responsible for maintaining seed dormancy?

Answer: Abscisic acid

Abscisic acid (ABA) promotes and maintains seed dormancy by inhibiting germination-related gene expression.

The scutellum found in grass seeds (monocots) is functionally equivalent to which structure in dicot seeds?

Answer: Cotyledon

The scutellum is the single, modified cotyledon of grass seeds that absorbs nutrients from the endosperm during germination.