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When the embryo is formed from any cell of the embryo sac other than the egg, the phenomena is called as

When the embryo is formed from any cell of the embryo sac other than the egg, the phenomena is called as Correct Answer Adventive embryony

Explanation:

Adventive embryony:

  • The formation of an embryo directly from the diploid sporophytic cells (nucellus or integuments) of the ovule (other than the zygote) is called adventive embryony.
  • It is seen in Citrus. 

Additional Information 

  • Parthenogenesis: Formation of the embryo from the unfertilized egg.
  • Apospory & Apogamy: Formation of the embryo from any other cell of embryosac (other than the egg) without fertilization.

Important Points 

  • Adventive embryony, Parthenogenesis, Apospory & Apogamy are all different types of Agamospermy.

Related Questions

Consider the following statements regarding recurrent type apomixis and choose the correct answer:
1. There is meiosis during the formation of megaspore
2. The embryo sac is diploid in nature
3. The embryo sac never develops from a cell of the archesporium
4. The development of embryo from a cell of an embryo sac other than egg is known as apospory
Consider the following statements and choose the correct answer:
1. In Oenothera type of monosporic embryo sac, the embryo develops from the micropylar megaspore of the tetrad
2. Antipodal cells are altogether absent in Oenothera type
3. The genus Trapa forms an 8-nucleate embryo sac of the Polygonurn type
4. Oenothera type of embryo sac development has been found to be a characteristic feature of the entire family Onagraceae
Consider with respect to HusserI's concept of phenomena.
1. Phenomena is a substantial unity that has real properties, real parts and real changes.
2. Phenomena is no substantial unity, that has no real parts and no real changes.
3. Phenomena has no nature, but only essence.
4. Phenomena have no essence, but only nature.
Which of the following statements is/are correct? 1. Monosporic development is the method of embryo sac formation from a single megaspore. 2. The egg apparatus consists of two synergids and one egg cell.
A monosporic, tetranuclear embryo-sac having an egg apparatus composed of two synergids and one egg, and a single polar nucleus is characteristic of all the members of
Consider the following statements.
1. Fertilisation of the egg takes place inside the embryo sac.
2. Fertilised ovum form the embryo.
3. Endosperm is generally triploid.
Which of the statements given above are correct?
A dealer offers sells half of the eggs that he has and another half an egg to Anurag. Then he sells half of the balance eggs and another half an egg to Deepak. Then he sells half of the balance eggs and another half an egg to Sivani. In the end he is left with just 7 eggs and he claims that he never broke an egg. How many eggs did he start with?
Consider the following statements regarding double fertilization and choose the correct answer:
1. At the time of the sperm's approach to the egg nucleus, the male nucleus has the appearance of a continuous thread rolled into a ball
2. It is only the presence of the two nucleoli which serves to distinguish the fertilized egg from the unfertilized egg
3. Finally, the male nucleolus increases in size and fuses with the female nucleolus thus closing the phenomenon of sexual union of the nuclei
4. The fusion of the male gamete with the secondary nucleus results in the formation of a sister embryo
Determine the correctness or otherwise of the following Assertion (A) and the Reason (R).
Assertion: Somatic embryogenesis in plants is a twostep process comprising of embryo initiation followed by embryo production.
Reason: Embryo initiation is independent of the presence of 2, 4-dichlorophenoxyacetic acid, whereas embryo production requires a high concentration of 2, 4-dichlorophenoxyacetic acid.
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Ants have been living on the earth for more than 100 million years and can be found almost anywhere on the planet. It is estimated that there are about 20000 different species of ants. For this reason ants have been called Earth's most successful species. If you watch ants for any length of time you will see that they really do communicate with each other and very effectively too. Ants communicate by touching each other with their antennae. Ants also use chemicals called pheromones to leave scent trails for other ants to follow. Ants build many different types of homes. Many ants build simple little mounds out of dirt or sand. Other ants use small sticks mixed with dirt and sand to make a stronger mound that offers protection from rain. Western Harvester ants make a small mound on top, but then tunnels up to 15 feet straight down to hibernate during winter. Ant mounds consist of many chambers connected by tunnels. Different chambers are used for nurseries, food storage, and resting places for the worker ants. Some ants live in wood like termites. Army ants don't make a home at all but travel in a large groups searching for food. Ants are social insects which means they live in large colonies or groups. Some colonies consist of millions of ants. There are three types of ants in each species, the queen, the sterile female workers and males. The male ants only serve one purpose, to mate with future queen ants and do not live very long. The queen grows to adulthood, mates, and then spends rest of her life laying eggs. A colony may have only one queen, or there may be many queens depending on the species. Ants go through four stages of development: egg, larva, pupa and adult.
Why are ants called the 'Earth's' most successful species?