Revision Biology Pollination & Fertilization IX Std Dr. Pramila Kudva

Agents of cross pollination 4. pollinated by elephants Across 4. pollinated by elephants Down 1. pollinated by insects 2. pollinated by water 3. pollinated by wind 5. pollinated by birds

2. structural barriers for pollination Across 2. structural barriers for pollination 4. anthers mature early 7. anthers and styles are located at different levels  Down 1. cross pollination 3. self pollination where pollen is deposited on the stigma of a different flower 4. stigma matures early 5. Self pollination 6. different maturation time for the anthers and style

1. Draw the pollen as shown below and neatly label the parts 5 2 4 3

2. Draw the mature ovule and label the parts. 1 2 3 a 4 7 3 b 6 5

Name the changes in the part of the flower after fertilization. Ovary Ovary Wall Ovule Placenta Integuments Secondary nucleus Egg Cell

Slide 1 Answers: Across 4 – Elephophilous Down Entomophilous Hydrophilous Anemophilous 5. Ornithophilous Slide 3 Answers: Antipodal cells Polar nuclei a & b – Integuments Egg cell Micropyle Synergids 7. Embryo sac Slide 2 Answers: 1 – Pit 2 – Exine 3 – intine 4 –Pollen tube nucleus 5 – Generative nucleus

Slide 4 Answers: Antipodal cells Polar nuclei a & b – Integuments Egg cell Micropyle Synergids 7. Embryo sac Slide 5 Answers: 1.Fruit 2, Pericarp 3. Seed 4. Stalk of the seed 5. Seed coat 6. Endosperm [Food storing tissue] 7. Zygote

1. What is Triple fusion Ans: two polar nuclei [2N] unite to form a seccondary nucleus and this unites with the sperm cell [1N] to form the endosperm [3 N]. 2. What is the function of the following: a) Endosperm Ans: It provides nutrition to the seed. It contains protein and starch b) Tube of the pollen Ans: To take the male gametes to the embryo sac

3. What is double fertilization 3. What is double fertilization? Ans: a) Egg cell unites with a male gamete / Sperm Cell [2 N] – Forms the Zygote b) 2 Polar Nuclei fuse with one male gamete /sperm cell [3 N] – Forms the Endosperm Nucleus / Secondary nucleus

4. Name the following: A) The nourishing liquid that holds the seeds Ans: Placenta b) Different maturation time of the androecium and gynoecium Ans: dichogamy c) Anthers mature earlier Ans: Protandry d) Stigma matures earlier Ans: Protogyny

e) Mechanical barrier that favours cross pollination Ans: Herkogamy f) Anthers and stigma grow at different heights Ans: Heterostyly

5. What is the difference between Autogamy and Geitonogamy? Autogamy is pollination in the same flower Geitonogamy is pollination between the flowers of the same plant but different flowers.

6. In which pollination do you find a) Floating Pollen Ans: Hydrophilous b) Stigma hanging outside the flower Ans: Anemophilous c) Flowers with nectar Ans: Entomophilous

d) Large flowers on the ground Ans: Elephophilous e) Bright flowers without nectar Ans: Ornithophilous

Give one word for the following Give one word for the following. A) Pollen grain of the flower fail to fertilize the egg cell of the same flower. Ans: Self sterility B) Grooves on the petals that lead to nectaries Ans: Honey guides or nectary guides C) Transference of pollen to the stigma of a different flower on the same plant Ans: Geitonogamy