Why are pollen tubes necessary for seed plants? -Biology

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Description : Why are pollen tubes necessary for seed plants? -Biology

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Description : Conifers differ from grasses in the (a) formation of endosperm before fertilization (b) production of seeds from ovules (c) lack of xylem tracheids (d) absence of pollen tubes.

Last Answer : (a) formation of endosperm before fertilization

Description : When embryosac receives two or more than two pollen tubes the sperm nucleus fusing with the egg nucleus may be derived from one pollen tube and one fusing with the polar nuclei may be derived from other pollen tube, the phenomenon is termed as

Last Answer : When embryosac receives two or more than two pollen tubes the sperm nucleus fusing with the egg nucleus may be derived from one pollen tube and one fusing with the polar nuclei may be derived from other pollen tube, the phenomenon is termed as – Heterofertilization

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 : Polyploidy level of testa and pollen mother cell of seed

Last Answer : Ans. 2n

Description : Metaxenia is the impact of a. Pollen on seed b. Pollen on fruit c. Pollen on ovule d. Pollen on ovary

Last Answer : Pollen on ovule

Description : What is the function of germ pore? (a) Emergence of radicle (b) Absorption of water for seed germination (c) Initiation of pollen tube (d) Release of male gametes

Last Answer : (c) Initiation of pollen tube

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 : 3What is the function of germ pore?a)Initiation of pollen tubeb)Release of male gametesc)Emergence of radicled)Absorption of water for seed germination

Last Answer : a)Initiation of pollen tube

Description : Which of the following nourishes a developing seed? a) pollen tube b) nectar c) endosperm d) zygote

Last Answer : ANSWER: C -- ENDOSPERM

Description : In angiosperm, triple fusion is necessary for the formation of: (a) Embryo (b) Pollen (c) Endosperm (d) Leaf

Last Answer : Ans. ((c))

Description : Before, germination of pollen, the moisture necessary for pollen hydration is provided by

Last Answer : Before, germination of pollen, the moisture necessary for pollen hydration is provided by – Stigma

Description : Pick out the wrong statement. (A) Longer tubes are less expensive per unit heat transfer area as compared to shorter tubes (B) A cost index is merely a number for a given year ... butt welded joints are less expensive compared to lap welded joints, because squaring of plates is not necessary

Last Answer : (D) Plates with butt welded joints are less expensive compared to lap welded joints, because squaring of plates is not necessary

Description : Is soil necessary for seed germination? -Biology

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Description : Is water necessary for seed germination? -Biology

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Description : Why is water necessary for seed germination? -Biology

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Description : Is soil necessary for seed germination? -Biology

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Description : Is water necessary for seed germination? -Biology

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Description : Why is water necessary for seed germination? -Biology

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Description : A condition in which either pollen is absent or non functional in flowering plants.

Last Answer : Ans. Male Sterility

Description : Pollen grains in plants are produced in?

Last Answer : flower

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 : Which one of the following statements is correct? (a) Cleistogamous flowers are always autogamous. (b) Xenogamy occurs only by wind pollination. (c) Chasmogamous flowers do not open at all. (d) Geitonogamy involves the pollen and stigma of flowers of different plants.

Last Answer : (a) Cleistogamous flowers are always autogamous.

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 : 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 : Match the following concerning essential elements and their functions in plants. Column-I Column-II (A) Iron (i) Photolysis of water (B) Zinc (ii) Pollen germination (C) Boron (iii) Required for chlorophyll biosynthesis (D) Manganese (iv) IAA biosynthesis

Last Answer : (c) (iii) (iv) (ii) (i)

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 : 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 : In hybridization this is not part of the technique used a) Transfer pollen b) Collect pollen c) Emasculate d) Use of two plants to bridge the stems together 

Last Answer : d) Use of two plants to bridge the stems together

Description : $ Seive tubes in plants are formed of enucleated cells called seive members. ! All the activities of a seive cell are controlled by nucleated parenchy

Last Answer : $ Seive tubes in plants are formed of enucleated cells called seive members. ! All the activities of a seive ... wrong D. If both As and R are wrong.

Description : Identify the two components of Phloem tissue that help in transportation of food in plants (a) Phloem parenchyma & sieve tubes (b) Sieve tubes & companion cell. (c) Phloem parenchyma & companion cell. (d) Phloem fibres and sieve tubes

Last Answer : (b) Sieve tubes & companion cell.

Description : The form of the fuel in U.S. commercial nuclear power plants is which of the following: w) uranium oxide ceramic pellets x) atomic vapor y) uranium metal tubes z) uranium solution in water

Last Answer : ANSWER: W -- URANIUM OXIDE CERAMIC PELLETS

Description : The tillage aims to reduce tillage to the minimum necessary for ensuring a good seed-bed, rapid germination, satisfactory stands and favourable growing condition?

Last Answer : Ans.Minimum tillage

Description : What is the difference between Pollen and Pollenium? -Biology

Last Answer : The male gamete containing structure in a flower is called pollen. A mass of pollen grains from the same flower is called pollenium. In a pollenium, the pollen grains are held together by a sticky substance and all the pollen grains are thus transferred together, as is Calotropis

Description : Part of gynoecium that determines the compatible nature of pollen grain. -Biology

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Description : why sterile tissues degenerate in anther during the maturation of pollen grain -Biology

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Description : Role of tapetum in the formation pollen-grain wall? -Biology

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Description : What is the difference between Pollen and Pollinium? -Biology

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Description : Where is pollen produced in a gymnosperm? -Biology

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Description : Pollen grain of hibiscus? -Biology

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Description : Factors which stimulate pollen tube germination. -Biology

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Description : What is a pollen tube? -Biology

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Description : What stimulates the pollen tube to grow? -Biology

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Description : Explain the structure of pollen grain? -Biology

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Description : Function of pollen tube? -Biology

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Description : Why is the growth of a pollen tube important? -Biology

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Description : Why is the growth of a pollen tube important? -Biology

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Description : What is the function of the pollen tube? -Biology

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Description : Growth of pollen tube. -Biology

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Description : Pollen tube attraction near ovule is facilitated by -Biology

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