Description : 10. “Cleistogamous flowers are invariably autogamous because” (a) These flowers do not open at all. (b) There is no chance of cross – pollen landing on the stigma. (c) These flowers have exposed anthers and stigma. (d) These flowers are wind pollinated.
Last Answer : (a) These flowers do not open at all.
Description : In an angiosperm, how many microspore mother cells are required to produce 100 pollen grains? (a) 75 (b) 100 (c) 25 (d) 50
Last Answer : (c) 25
Description : Formation of 8-nucleate embryosac by pollen grains is also called as
Last Answer : Formation of 8-nucleate embryosac by pollen grains is also called as – Nemec phenomenon
Description : Wind pollinated flowers are (a) small, brightly coloured, producing large number of pollen grains (b) small, producing large number of dry pollen grains (c) large producing abundant nectar and pollen (d) small, producing nectar and dry pollen
Last Answer : (b) small, producing large number of dry pollen grains
Description : When pollen grains are transferred to the stigma? -Biology
Last Answer : answer:
Description : What are pollen grains? -Biology
Description : Where are pollen grains produced? -Biology
Description : What do pollen grains contain? -Biology
Description : Why were at least twenty pollen grains needed for each sugar concentration?
Last Answer : Anything less and the sample size would be too small for reliable data
Description : How are pollen grains adapted to help plant pollinations?
Last Answer : Some pollen grains have a spiky surface to help them sticky tothe bodies of insects.
Description : What are the two ways in which pollen grains are scattered?
Last Answer : Pollen is scattered by the wind or by animals.
Description : When pollen grains from flower of one plant transferred to receptive stigmas of flowers of another plant
Last Answer : Ans. Cross pollination/Allogamy
Description : When pollen grains from an another falls on receptive stigma of the same flowers
Last Answer : Ans. Self pollination
Description : Consider the following statements about pollination. 1. Transfer of pollen grains from the anther to ovules in the same flower or a different f lower is called pollination. 2. The pollination by wind is called anemophily. 3. Pollination is a ... 1 and 3 (b) 1, 2 and 4 (c) Only 2 (d) 1, 2, 3 and 4
Last Answer : Ans:(c)
Description : In dicots the pollen-grains possess : (1) two germ pores (2) three germ pores (3) four germ pores (4) one germ pore
Last Answer : (2) three germ pores Explanation: Pollen grains of monocots have one opening, while pollen grains of dicots have three openings. Pollengrains can be monocolpate (having one germ pore called germinal furrow e.g., monocots), bicolpate (2 germ pores) and tricolpate (3 germ pores e.g., dicots).
Description : The floral part that receives pollen grains during pollination is - (1 ovary (2) style (3) stigma (4) ovules
Last Answer : (3) stigma Explanation: The stigma is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. The stigma receives pollen at pollination and it is on the stigma that the pollen grain germinates. The style connects the stigma to the ovary.
Description : The floral part that produces pollen grains is (1) Sepal (2) Petal (3) Anther (4) Ovary
Last Answer : (3) Anther Explanation: The anther contains microsporangia. Each microsporangium contains pollen mother cells. These undergo meiosis, and produce pollen grains, which contain the male gametes (sperm). The pollen is released by the opening of the anther.
Description : The floral part that produces pollen grains is - (1 ) Sepal (2) Petal (3) Anther (4) Ovary
Last Answer : (3) Anther Explanation: Anther is the apical portion of a stamen, which produces the microspores or pollen grains. An anther normally comprises four pollen sacs arranged in two groups or lobes joined by the connective tissue to the filament
Description : The pollen grains of flowers pollinated by insects are : (1) smooth and dry (2) rough and sticky (3) rough and dry (4) large and, showy
Last Answer : (2) rough and sticky Explanation: Pollen grains are large sticky and heavy, usually with rough surfaces so that they can readily cling onto the insects bodies. They are sticky so that pollen grains settling on them are not easily displaced.
Description : Pollen grains in plants are produced in?
Last Answer : flower
Description : The transfer of pollen grains from the an- ther to the stigma is called?
Last Answer : pollination
Description : Which ones produce androgenic haploids in anther cultures? (a) Anther wall (b) Tapetal layer of anther wall (c) Connective tissue (d) Young pollen grains
Last Answer : (d) Young pollen grains
Description : In tissue culture medium, the embryoids formed from pollen grains is due to (a) cellular totipotency (b) organogenesis (c) double fertilization (d) test tube culture.
Last Answer : (a) cellular totipotency
Description : Which one of the following statements is wrong? (a) When pollen is shed at two-celled stage, double fertilisation does not take place. (b) Vegetative cell is larger than generative cell. (c) Pollen grains in some plants remain viable for months. (d) Intine is made up of cellulose and pectin.
Last Answer : (a) When pollen is shed at two-celled stage, double fertilisation does not take place.
Description : In grasses what happens in microspore mother cell for the formation of mature pollen grains? (a) One meiotic and two mitotic divisions (b) One meiotic and one mitotic divisions (c) One meiotic division (d) One mitotic division
Last Answer : (b) One meiotic and one mitotic divisions
Description : Transfer of pollen grains from the anther to the stigma of another flower of the same plant is called (a) xenogamy (b) geitonogamy (c) karyogamy (d) autogamy.
Last Answer : (b) geitonogamy
Description : Which one of the following statements is not true? (a) The flowers pollinated by flies and bats secrete foul odour to attract them. (b) Honey is made by bees by digesting pollen collected ... . (d) Pollen grains of some plants cause severe allergies and bronchial afflictions in some people.
Last Answer : (b) Honey is made by bees by digesting pollen collected from flowers.
Description : Which of the following are the important floral rewards to the animal pollinators ? (a) Floral fragrance and calcium crystals (b) Protein pellicle and stigmatic exudates (c) Colour and large size of flower (d) Nectar and pollen grains
Last Answer : (d) Nectar and pollen grains
Description : Which of the following statements is not correct? (a) Pollen germination and pollen tube growth are regulated by chemical components of pollen interacting with those of the pistil. (b) ... Insects that consume pollen or nectar without bringing about pollination are called pollen/ nectar robbers.
Last Answer : (c) 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.
Description : Which one of the following statements is not true? (a) Pollen grains of many species cause severe allergies. (b) Stored pollen in liquid nitrogen can be used in the crop breeding programmes. (c) Tapetum helps in the dehiscence of anther. (d) Exine of pollen grains is made up of sporopollenin.
Last Answer : (c) Tapetum helps in the dehiscence of anther.
Description : Winged pollen grains are present in (a) mustard (b) Cycas (c) mango (d) Pinus
Last Answer : (d) Pinus.
Description : Pollen grains can be stored for several years in liquid nitrogen having a temperature of (a) –120°C (b) –80°C (c) –196°C (d) –160°C
Last Answer : (c) –196°C
Description : The plant parts which consist of two generations- one within the other (1) pollen grains inside the anther (2) germinated pollen grain with two male gametes (3) seed inside the fruit (4) embryo sac inside the ovule (a) (1) only (b) (1), (2), and (3) (c) (3) and (4)
Last Answer : (d) (1) and (4).
Description : Parthenocarpic tomato fruits can be producedby (a) treating the plants with phenylmercuric acetate (b) removing androecium of flowers before pollen grains are released (c) treating the plants with low concentrations of gibberellic acid and auxins (d) raising the plants from vernalized seeds
Last Answer : (c) treating the plants with low concentrations of gibberellic acid and auxins
Description : In gymnosperms, the pollen chamber represents (a) a cavity in the ovule in which pollen grains are stored after pollination (b) an opening in the megagametophyte through which the pollen tube approaches the ... pollen grains develop (d) a cell in the pollen grain in which the sperms are formed.
Last Answer : (c) the microsporangium in which pollen grains develop
Description : Which of the following nutrient is involved in reproduction in plants and germination of pollen grains ? a. Boron b. Calcium c. Potassium d. Sulphur
Last Answer : a. Boron
Description : Pollen grains can be stored for several years in liquid nitrogen having a temperature of (1) –120°C (2) –80°C (3) –196°C (4) –160°C
Last Answer : (3) –196°C
Description : Winged pollen grains are present in (1) Mustard (2) Cycas (3) Mango (4) Pinus
Last Answer : (4) Pinus
Description : The transfer of pollen grains from anther to stigma is called; a) Fertilization b) pollination c) Microsporogenesis d) Polyembryony
Last Answer : Ans. b) Pollination
Description : Which layer of microsporangium provides nutrition to the developing pollen grains: a) Epidermis b) Endothecium c) Tapetum d) All
Last Answer : Ans : c) Tapetum
Description : Which one of the following statements is wrong?a)Pollen grains in some plants remain viable for monthsb)Intine is made up of cellulose and pectinc)When pollen is shed at two-celled state, double fertilization does not take placed)Vegetative cell is larger than generative cell
Last Answer : c)When pollen is shed at two-celled state, double fertilization does not take place
Description : Transfer of pollen grains from the anther to the stigma of another flower of the same plant is called:a) Autogamyb) Xenogamyc) Geitonogamyd) Karyogamy
Last Answer : c) Geitonogamy
Description : The process involving emasculation of the flower before anthesis and depositing pollen grains on the cut end of the ovary is called as
Last Answer : The process involving emasculation of the flower before anthesis and depositing pollen grains on the cut end of the ovary is called as – Intra-ovarian pollination
Description : Effect of pollen grains on the properties of endosperms is called as
Last Answer : Effect of pollen grains on the properties of endosperms is called as – Xenia
Description : In Angiosperms, during pollination, the pollen grains are mostly
Last Answer : In Angiosperms, during pollination, the pollen grains are mostly – Bicellular
Description : Pollen grains of angiosperms are
Last Answer : Pollen grains of angiosperms are – Partially developed male gametophyte