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Formation of seed is an important adaptation for the land.
The evolution of seed allowed plants to to decrease their dependency upon water for reproduction.
It is needed that the seed remain dormant for a long period because condition is not favorable all the time .So soil plays an important role in evolution.
Pollination is important aspect seed can be dispersed far and wide by many ways such as wind ,bird ,animal etc.Thus increasing the chances of finding good conditions.The protection is enhanced by seed coat.
Pollination is a process of transferring pollen from one flower to another while fertilization occur after successful transfer of pollination .In Fertilization fusion of male and female gamete occurs in plant.
Another difference is ,only flowering plant gone through the process of pollination,where as fertilization is common in all living organism.
In pollination ,medium like wind,animal,is required while in fertilization there is no medium is required.
Pollination is external mechanism while fertilization is internal mechanism.
In pine fertilization occurs 15 minutes after pollination.
Pine trees are conifers carry both male and female sporophyll on same mature sporophyte.Pine generating two different type of spores male microspores and female megaspores .
In the male cone the microsporocytes give rise to pollen grains by meiosis ,in the spring season pollen are released and carried by wind.Some gametophyte will land on female cone.The pollen tube develop slowly as the generative cell in the pollen grain divides into two haploid cell by mitosis.
when mature each microspore germinates means cell division starts.
pollen cones are formed ,female cone form near the tip of branches.At the time of pollination scales are separated to allow pollen to fall between them to reach the ovules.
Each fertile scale has 2 ovules on its upper surface.
Ovule consist of a sporangium ,at the center of it a special cell called sporocyte,divideds into 4 haploid spores by meiosis
Megaspore now germinates to form gametophyte.one of the cell inside pollengrain divides into 2 sperm cell which travel along pollen tube to reach an egg.
Zygote formation and zygote divides into several nuclei.they are arranged themselves into 4 tier of 4 cells.
The end tier become 4 embryo cell,as the 4 embryo cell are pushed deeper into the gametophyte they split apart into 4 seperate suspensors.The 4 embryo generate and become multicellular.
Surviving embryo enlarges as it form root tip,shoot tip and several seed leaves.
ovules have been developing into seed the entire female cone has become large and woody.
In what way was the seed an important adaptation in the evolution of plants? Explain the difference between pollination and fertilization. How much time elapses between these two processes in pin...
b ory Marvel Observation Flowering Plant Life Cycle Use Figure 10.6 as a guide to describe the life cycle of flowering plants 1. The parts of the flower involved in reproduction are the and the 2. The there the top of the same has two sacs, which produce - by meiosis. 3. Within an ovule, a megaspore mother sellepoes meliosis to produce four three of which die 4. A microspore underpoes mitosis and becomes a - the male gametophyte. 5....
ws. Unless you need to edit it's safer to stay in Protected View Enable Editing Alternation of generations describes plant life cycles. There are ſhow many?) generations. • The gametophyte generation begins when the process of forms (ploidy) cells. The gametophyte generation ends when a (ploidy) _ is formed by the process of_ Figure 38.4 Alternation of generations: What are the two generations in the plant life cycle? What is the male gametophyte? Female? The microsporangium in the pollen sac....
All land plants have single cell haploid and single cell diploid states single cell haploid and multicellular diploid states multicellular haploid and single cell diploid states multicellular haploid and multicellular diploid states A. B. C. D. E. diplontic life cycles 7. A gametophyte is B. c. 2n 3n 4n 5n A sporophyte is In 2n 3n C. D. E. 9. The dominant (bigger) state in mosses, liverworts, and hornworts is the A gametophyte sporophyte C. sporangium D. archegonium E. antheridium...
Plantae: 1. Which of the following correctly describes an evolutionary trend that occurred as land plants evolved? 2. Becoming seedless b. Producing one type of spole Producing nonmotile wametes d. Haploid generation becoming dominant 2. Which of the following occurs in the Ilie cycle of both masses and anglosperms? a. The sporophyte is the dominant generation b. The gametophyce is the dominant gcneration c Spores develop into sporophytes d. The sporophyte products sporcs 3. The evolution of which of the...
Describe the procedures described throughout this laborotory activity: 10.1 Flowers external: 10 Seed Plants II: Angiosperms After completing this exercise, you will be able to 1. define heterosporous, angiosperm, fruit, pollination, double fertiliation, endosperm, aeed, germina tion, annual, biennial, perennial 2. describe the significanceo 3. identify the structures of the flower: 4. recognize the structures and events (those in boldface) that take place in angiosperm reproduction; 5. describe the origin and function of fruit and seed; 6. identify the characteristics...