Chapter 1: Sexual Reproduction in Flowering Plants — Online MCQ Test
BIOLOGY · Grade 12 · CBSE(NCERT)
Practice Chapter 1: Sexual Reproduction in Flowering Plants with a free chapter-wise online MCQ test.
This chapter covers: Flower Morphology Microsporogenesis Megasporogenesis Pollination Double Fertilisation Embryo Sac Pollen Grain Seed Formation Fruit Development Angiosperms.
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter 1: Sexual Reproduction in Flowering Plants — Important Questions & Answers
What is the functional unit of sexual reproduction in flowering plants?
- A. Leaf
- B. Flower
- C. Stem
- D. Root
Answer: B. Flower
The flower is the reproductive organ of flowering plants and contains both male and female reproductive structures.
The flower is the reproductive organ of flowering plants and contains both male and female reproductive structures.
Which of the following is NOT a part of the flower's male reproductive system?
- A. Anther
- B. Filament
- C. Carpel
- D. Pollen grain
Answer: C. Carpel
Carpel is the female reproductive part of the flower; anther, filament, and pollen grain are parts of the male stamen.
Carpel is the female reproductive part of the flower; anther, filament, and pollen grain are parts of the male stamen.
The process by which pollen grains are produced from microspore mother cells is called:
- A. Megasporogenesis
- B. Microsporogenesis
- C. Gametogenesis
- D. Sporulation
Answer: B. Microsporogenesis
Microsporogenesis is the formation of microspores from the microspore mother cell (diploid) through meiosis, occurring in the anther.
Microsporogenesis is the formation of microspores from the microspore mother cell (diploid) through meiosis, occurring in the anther.
How many functional megaspores are typically produced from one megaspore mother cell?
- A. One
- B. Two
- C. Three
- D. Four
Answer: A. One
In most flowering plants, meiosis of the megaspore mother cell produces four megaspores, but only one survives and functions; the others degenerate.
In most flowering plants, meiosis of the megaspore mother cell produces four megaspores, but only one survives and functions; the others degenerate.
In a typical polygonum-type embryo sac, how many nuclei are present at maturity?
- A. Three
- B. Five
- C. Seven
- D. Nine
Answer: C. Seven
The mature polygonum-type embryo sac typically contains 7 nuclei arranged as: 3 in the egg apparatus, 2 polar nuclei, and 2 antipodal cells.
The mature polygonum-type embryo sac typically contains 7 nuclei arranged as: 3 in the egg apparatus, 2 polar nuclei, and 2 antipodal cells.
Which structure in the embryo sac is responsible for absorbing nutrients from the nucellus?
- A. Egg cell
- B. Synergids
- C. Central cell
- D. Antipodal cells
Answer: D. Antipodal cells
Antipodal cells are located at the chalazal end and help in nutrient absorption from the nucellus for the developing embryo.
Antipodal cells are located at the chalazal end and help in nutrient absorption from the nucellus for the developing embryo.
Which statement correctly describes the relationship between fruit and seed formation?
- A. Fruits develop before seeds form
- B. Seeds develop independently of fruit formation
- C. Fruit develops from the ovary after fertilization; seeds develop from ovules
- D. Fruits and seeds are the same structure
Answer: C. Fruit develops from the ovary after fertilization; seeds develop from ovules
After double fertilization, the ovary wall develops into the fruit (pericarp) while ovules mature into seeds containing the embryo and endosperm.
After double fertilization, the ovary wall develops into the fruit (pericarp) while ovules mature into seeds containing the embryo and endosperm.
Analyze the significance of the nucellus in ovule structure and function:
- A. It serves only as a protective layer with no nutritional role
- B. It is the site of meiosis for megaspore formation and provides nutrients via antipodal cells
- C. It prevents fertilization until the right time
- D. It produces pollen grains directly
Answer: B. It is the site of meiosis for megaspore formation and provides nutrients via antipodal cells
The nucellus contains the megaspore mother cell and provides nutrients to the developing embryo sac through cell absorption by antipodal cells.
The nucellus contains the megaspore mother cell and provides nutrients to the developing embryo sac through cell absorption by antipodal cells.
A botanist observes that in a particular angiosperm species, the megaspore mother cell undergoes meiosis to produce four spores, but only one develops into a functional embryo sac. The three others degenerate. This pattern is most likely due to:
- A. Mutation during meiosis
- B. Nutritional competition where the developing megaspore suppresses others through differential nutrient allocation
- C. Random genetic events
- D. Chromosomal abnormalities in three megaspores
Answer: B. Nutritional competition where the developing megaspore suppresses others through differential nutrient allocation
This is a developmental pattern where the first-formed megaspore receives maximum nutrient allocation from the nucellus, while others degenerate due to limited resources.
This is a developmental pattern where the first-formed megaspore receives maximum nutrient allocation from the nucellus, while others degenerate due to limited resources.
During pollen grain maturation, if the generative cell fails to divide before pollination occurs, what would be the immediate consequence upon pollen tube entry into the embryo sac?
- A. Successful fertilization with double fertilization events
- B. Delayed fertilization until generative cell division completes within the pollen tube
- C. Failure of fertilization due to absence of sperm cells
- D. Production of abnormal endosperm with altered ploidy
Answer: B. Delayed fertilization until generative cell division completes within the pollen tube
The generative cell divides during pollen tube growth (or after entry in some species); if not divided beforehand, it completes division within the pollen tube before reaching the egg.
The generative cell divides during pollen tube growth (or after entry in some species); if not divided beforehand, it completes division within the pollen tube before reaching the egg.