Sexual reproduction in flowering plants - NEET 2020 - Live SessionContact Number: 9667591930 / 8527521718Sexual reproduction in flowering plants - NEET 2020 - Live SessionContact Number: 9667591930 / 8527521718Consider the following features seen in a plant:
I. Male and female reproductive organs are generally found in separate flowers.
II. The male flowers having a number of long filaments terminating in exposed stamens.
III. The female flowers having long, feather-like stigmas.
The flowers of this plant would most likely be pollinated by:
(1) Wind
(2) Water
(3) Bees
(4) Birds
The cells of which of the following layers of the anther wall are multinucleated due to endomitosis?
(1) Epidemis
(2) Endothecium
(3) Middle layer
(4) Tapetum
A typical angiosperm anther is dithecous which means that it is:
1. One lobed and the lobe has two theca
2. Two lobed and each lobe has two theca
3. Two lobed and each lobe has one theca
4. Four lobed and each lobe has two theca
The pistil of Papaver is:
1. Monocarpellary
2. Multicarpellary apocarpous
3. Multicarpellary syncarpous
4. Absent
How many of the nuclei in the female gametophyte in angiosperms are surrounded by cell wall?
(1) 5
(2) 6
(3) 7
(4) 8
The micropyle remains as a small pore in the seed coat. During germination, this facilitates entry of:
I. Oxygen
II. Water
(1) Only I
(2) Only II
(3) Both I and II
(4) Neither I nor II
If a flower is to be pollinated by moths, it should
(1) be heavily scented
(2) be shaped like a tulip
(3) close about noon
(4) be brightly colored
A fertilized embryo sac of an angiosperm contains:
I. Haploid cells
II. Diploid cells
III. Triploid cells
1. I and II only
2. I and II only
3. II and III only
4. I, II and III
Female flowers remain submerged in water and the pollen grains are released inside the water in:
1. Sea grasses
2. Vallisneria
3. Water lily
4. Water hyacinth
Seeds offer several advantages to angiosperms. Seed formation is more dependable because:
1. Seeds have better adaptive strategies for dispersal
2. Reproductive processes become independent of water
3. Hard seed coat provides protection to the young embryos
4. They generate new genetic combinations leading to variations
The process of formation of microspores from a pollen mother cell is called
(1) Megasporogenesis
(2) Microsporogenesis
(3) Megagametogenesis
(4) Microgametogenesis
Choose the correct option with respect to the function of the germ pore.
(1) It allows growth of pollen tube
(2) It allows water absorption in seed
(3) It helps dehiscene of pollen grain
(4) More than one option is correct
The thin and continuous wall layer of pollen is
(1) Exine
(2) Intine
(3) Germ pore
(4) Endothecius
The two-celled stage of mature pollen grain consists of
(1) Vegetative cell, generative cell
(2) Vegetative cell, one male gamete
(3) Two male gametes
(4) Generative cell, one male gamete
The pollen viability period of rice and pea respectively,is
(1) 30 minutes and several months
(2) Several months and 30 minutes
(3) Few days and few months
(4) Few days in both the cases
The nutritive tissue present in the ovule is called
(1) Nucellus
(2) Funicle
(3) Embryo
(4) Integuments
Geitonogamy is
(1) Genetically autogamous
(2) Ecologically autogamous
(3) Genetically allogamous
(4) Functionally autogamous
Examples of water pollinated flowers are
(1) Zostera, Lotus, water lily
(2) Lotus, Vallisneria, Hydrilla
(3) Potamogeton, Vallisneria, Lotus
(4) Vallisneria, Hydrilla, Zostera
Dioecious condition prevents
(1) Autogamy
(2) Geitonogamy
(3) Xenogamy
(4) Both (1) & (2)
Exalbuminous seeds are of
(1) Wheat, Pea, groundnut
(2) Castor, pea, groundnut
(3) Pea, groundnut, beans
(4) Wheat, castor, rice
The sheath enclosing plumule and radicle respectively in monocot seed are
(1) Coleoptile and coleorhiza
(2) Coleorhiza and coleoptile
(3) Scutellum and epiblast
(4) Aleurone layer and pericarp
Choose the odd with respect to gynoecium
(1) Gynoecium represents the female reproductive part of flower
(2) The gynoecium may be syncarpous or apocarpous
(3) The number of ovules in papaya and mango is one
(4) The ovules are attached to placenta
The type of flowewrs which always produce seeds even in the absence of pollinators
(1) Chasmogamous flowers
(2) Cleistogamous flowers
(3) Bisexual flowers
(4) Unisexual flowers
Which is incorrect statement?
(i) Each cell of sporogenous tissue in anther is capable of giving rise to microspore tetrad.
(ii) The pollen grain represent male gametophyte.
(iii) Pollen grains are usually triangular and 10-15 in diameter.
(iv) Sporopollen is one of the most resistance organic material which can be destroyed only by strong acids and alkali.
(1) (i), (ii) are incorrect but (iii), (iv) are correct
(2) (iii), (iv) are incorrect but (i), (ii) are correct
(3) (i),(iii) are incorrect but (ii), (iv) are correct
(4) (ii), (iv) are correct but (i), (iii) are incorrect
An angiospermic plant is having 24 chromosomes in its leaf cells. The number of chromosomes present in synergid, pollen grain, nucellus & endosperm will be respectively.
(1) 12, 12, 12, 72
(2) 8, 8, 12, 36
(3) 12, 12, 24, 36
(4) 12, 12, 12, 36
The devices to discourage self pollination are
(1) Pollen release and stigma receptivity is not synchronised
(2) Anther and stigma are placed at different position
(3) Rejection of pollen by stigma of the same flowers
(4) All of these
select incorrect statement (with respect to artificial hybridisation)
(1) Emasculation is removal of anther in their mature condition from bisexual flower
(2) Emasculation is not required in male sterile plants
(3) Unisexual female flower is bagged in bud condition to prevent contamination
(4) Emasculated flowers are bagged in bud condition
Which of the following has proved helpful in preserving pollen as fossils?
(1) Pollenkitt
(2) Cellulosic
(3) Sporopollenin
(4) Oil content
Double fertilization is
(1) Fusion of two male gametes of a pollen tube with two different eggs
(2) Fusion of one male gamete with two polar nuclei
(3) Syngamy and triple fusion
(4) Fusion of two male gametes with one egg
Functional megaspore in an angiosperm develops into
(1) Ovule
(2) Endosperm
(3) Embryo sac
(4) Embryo
Which one of the following statements is not true?
(1) Stored pollen in liquid nitrogen can be used in the crop breeding programmes
(2) Tapetum helps in the dehiscene of anther
(3) Exine of pollen grains is made up of sporopollenin
(4) Pollen grains of many species cause severe allergies
Which of the following is not correct?
(1) Some reptiles have also been reported as pollinators in some plant species
(2) Pollen grains of many species can germinate on the stigma of a flower, but only one pollen tube of the same species grows into the style.
(3) Insects that consume pollen or nectar without bringing about pollination are called pollen / nectar robbers
(4) Pollen germination and pollen tube growth are regulated by chemical components of pollen interacting with those of the pistil
Seed formation without fertilization in flowering plants involves the process of
(1) Apomixis
(2) Sporulation
(3) Budding
(4) Somatic hybridization
Male gametophyte in angiosperms produces
(1) Three sperms
(2) Two sperms and a vegetative cell
(3) Single sperm and a vegetative cell
(4) Single sperm and two vegetative cells
Filiform apparatus is characteristic feature of:
(1) Synergids
(2) Generative cell
(3) Nucellar embryo
(4) Aleurone cell
Which one of the following may require pollinators, but is genetically similar to autogamy?
(1) Cleistogamy
(2) Geitonogamy
(3) Xenogamy
(4) Apogamy
Function of filiform apparatus is to
(1) Recognize the suitable pollen at stigma
(2) Stimulate division of generative cell
(3) Produce nectar
(4) Guide the entry of pollen tube
Perisperm differs from endosperm in
(1) Having no reserve food
(2) Being a diploid tissue
(3) Its formation by fusion of secondary nucleus with several sperms
(4) Being a haploid tissue
Which one of the following statements is wrong?
(1) When pollen is shed at two-celled stage, double fertilization does not take place
(2) Vegetative cell is larger than generative cell
(3) Pollen grains in some plants remain viable for months
(4) Intine is made up of cellulose and pectin
What is common between vegetative reproduction and Apomixis?
(1) Both occur round the year
(2) Both produces progeny identical to the parent
(3) Both are applicable to only dicot plants
(4) Both bypass the flowering phase
What would be the number of chromosomes of the aleurone cells of a plant with 42 chromosomes in its root tip cell?
(1) 21
(2) 42
(3) 63
(4) 84
Which of the following pairs of plant structures has haploid number of chromosomes?
(1) Egg nucleus and secondary nucleus
(2) Megaspore mother cell and antipodal cells
(3) Egg cell antipodal cells
(4) Nucellus and antipodal cells
Through which cell of the embryo sac, does the pollen tube enter the embryo sac?
(1) Egg cell
(2) Central cell
(3) Persistant synergid
(4) Degenerated synergid
If an angiospermic male plant is diploid and female plant tetraploid, the ploidy level of endosperm will be
(1) Tetraploid
(2) Pentaploid
(3) Haploid
(4) Triploid
Anemophily type of pollination is found in
(1) Salvia
(2) Bottle
(3) Vallisneria
(4) Coconut