Sexual Reproduction in Flowering Plants quiz

The innermost wall layer of the microsporangium that nourishes developing pollen grains is the:

In over 60% of angiosperms, pollen grains are shed at the:

The number of nuclei and cells in a typical angiosperm embryo sac is:

The filiform apparatus is present in the:

Cleistogamous flowers are found in:

Pollination by water occurs in:

The primary endosperm nucleus is:

Coconut water is an example of:

A seed in which the remnant of nucellus persists is said to have:

Polyembryony is commonly seen in:

Why are pollen grains well preserved as fossils? (2 marks)

Explain how pollen grains are stored in pollen banks. (2 marks)

What is emasculation? When and why is it done? (2 marks)

Distinguish between chasmogamous and cleistogamous flowers. (2 marks)

Why is the endosperm formed before the embryo? (2 marks)

What are false fruits? Give two examples. (2 marks)

Distinguish between albuminous and non-albuminous seeds. (2 marks)

How long have seeds of Lupinus arcticus and Phoenix dactylifera been known to remain viable? (2 marks)

Why do apomictic hybrids benefit farmers? (2 marks)

State two adaptations of wind-pollinated flowers. (2 marks)

Calculate the number of meiotic divisions needed to produce 200 seeds. Explain why the number for male gametes is smaller than for female gametes. (3 marks)

The endosperm of a plant has 36 chromosomes. Calculate the chromosome number in the egg, the zygote, the pollen grain and a root cell. (3 marks)

An ovary has 40 ovules. If 75% of them are fertilised and develop into seeds, how many seeds are formed? How many male gametes were used in total, considering double fertilisation? (3 marks)

A single anther of a flower produces about 4,000 pollen grains. How many microspore mother cells underwent meiosis? If the flower has 6 anthers, calculate the total pollen grains produced. (3 marks)

In a pollen viability test, 400 pollen grains were placed on a germination medium and 320 germinated. Calculate the percentage viability. If pollen viability falls by 25% of its original value per day, what will it be after two days? (3 marks)

Read the passage and answer the questions. A plant breeder wants to cross two varieties of wheat. She removes the anthers from the flowers of the female parent before they dehisce and covers the flowers with butter paper bags. When the stigma becomes receptive, she dusts pollen from the male parent and rebags the flowers. (i) What are the two techniques described? (ii) Why is bagging necessary? (iii) Is emasculation needed if the female parent has unisexual flowers? (5 marks)

Read the passage and answer the questions. In Vallisneria, the female flowers reach the surface of water on long stalks, while the male flowers or pollen grains are released onto the surface and carried passively by water currents. (i) Name this type of pollination. (ii) How are pollen grains of seagrasses like Zostera protected from wetting? (iii) Why are flowers pollinated by water not very colourful? (5 marks)

Read the passage and answer the questions. A farmer noticed that his mango trees produce seeds that give rise to several seedlings each, which are identical to the parent tree. Hybrid seeds of other crops must be bought every year. (i) Name the phenomenon in mango. (ii) How does it arise? (iii) Why would apomixis be useful in hybrid seed industry? (5 marks)

Read the passage and answer the questions. In many cities, people suffer from allergies during certain seasons. Parthenium, introduced into India as a contaminant with imported wheat, is a major cause of pollen allergy. (i) Name two disorders caused by pollen allergy. (ii) Why are pollen grains of Parthenium dispersed widely? (iii) State one beneficial use of pollen grains. (5 marks)

Read the passage and answer the questions. A student examined a mature seed of maize and a mature seed of pea. The maize seed had a large food-storing tissue outside the embryo, while in pea the food was stored in two thick cotyledons. (i) Classify the two seeds as albuminous or non-albuminous. (ii) What is the single cotyledon of maize called? (iii) Name the protective sheaths around the plumule and radicle in maize. (5 marks)

Describe microsporogenesis and the structure of a mature pollen grain with labelled diagrams of the T.S. of an anther and a pollen grain. (6 marks)

Describe megasporogenesis and the development of the female gametophyte with labelled diagrams. (6 marks)

Describe the types of pollination and the agents of pollination with examples. Draw labelled diagrams of a wind-pollinated and an insect-pollinated flower. (6 marks)

Explain double fertilisation in angiosperms with a labelled diagram of an embryo sac at the time of fertilisation, and describe the development of endosperm and embryo. (6 marks)

Draw labelled diagrams of a dicot embryo and the L.S. of a maize grain. Explain seed formation, seed dormancy and the advantages of seeds to angiosperms. (6 marks)