1. Write the Important definitions of the chapter 'Reproduction' (class 10) ; Write in Copy .
2.) How do hens lay eggs ?
3.) The journey from 'young ones' to 'Adults'. ( assuming as the example of frog )
Answers
(1.) ANSWER : Refers to the given attachment ↑
(2.) ANSWER : In hens, Fertilisation is internal as it takes place inside the body of the female. But unlike humans, the development of their young ones take place outside the body of the female bird. This is, therefore, the zygote starts starts dividing and move down the Oviduct. As it moves down, A number of protective layers get formed around it. The egg shells is made of calcite (A crystalline form of calcium carbonate ).
The embryo develops inside the egg for (around) 21 days (the incubation period) , after which the chick get fully developed. During the incubation period, the eggs required a specific temperature, this this is provided by the hen sitting on the eggs. (Sometimes, this this is done artificially by keeping the eggs in an Incubator). Finally , the eggs shell breaks down and the chick comes out. This process is called Hatching.
(3.) ANSWER : All young ones grow to form adults regardless of whether they have hatched from the egg or born directly. In many animals the young one, at birth, is a miniature (smaller) version of the adult form. The development of such young ones (into adults), is known as Direct Development.
In some animals, the young ones, initially, are very different from their adults. For example, a tadpole looks very different from an adult frog. Similarly, a caterpillar, or the pupa of silk moth, are a numbers of feature in the adults frogs that are not present in the tadpole, or at the larva stage. For example, a frog has lungs but a tadpole has gills for respiration. This type of development is known as indirect development.
A marked, and more aur less abrupt development change in the structure and habit of an animal (as in case of a butterfly or frog) , occurring during its life cycle, is termed as Metamorphosis.
During the life cycle of an amphibian, eggs are laid in water. A tadpole then emerges from the egg and swims freely in the water. The tadpole has gills, a tail and a small circular mouth. The tadpole grows until it begins to undergo metamorphosis. Metamorphosis begins with the development of the Hind legs followed by the front legs ; then the lungs develop. The tadpole then begins to swim to the surface of water to breathe. The intestine shortens to adapt the animal to a carnivorous diet. In case of frogs, the tale get absorbed by the water during the last stages of metamorphosis. A tailed tadpole, thereby, changes into a tail - less frog.
Answer:
2 ) Eggs are formed inside the hen's body when her ovary releases the egg yolk into the oviduct.
If a rooster mates with her during this time period, the egg will be fertilized when it is traveling through the oviduct.
The hens lay eggs through their cloaca, or vent.
3) It's common to view adolescence as one thing and to see some kids as easy ... Think of it as a journey from childhood to adulthood and think of the journey ... stages, early adolescence, late adolescence and young adulthood.
The journey from young ones to adults is called Adolescence.