Question

The Graafian follicle is characteristic of
(a)Reptiles
(b)Amphibians
(c)Mammals
(d)All of these

Answer 1

Hint: Graffian follicle is found in the organisms that are characterized by mammary glands and the offspring develop inside the womb of mother for a particular period of time.

Complete answer:
The Graafian follicle or the ovarian follicle is found in mammals. The structure is fluid filled and helps in the development of ovum in different stages before the process of ovulation. The rest mentioned animals are oviparous.

Additional Information:
 Initially, the Graafian follicles are immature and start as primordial follicles. They are present in female animals before birth and have a single oocyte inside them.
When the menstrual cycle begins the immature primordial follicles start growing and they create a space around the ovum which is fluid-filled. This cavity is then called antrum.
Now one of these follicles grows in size and gets bigger and thus known as the graafian follicle. In the menstrual cycle on the 14th day when there is a surge in the LH hormone this big graafian follicle bursts and it releases the ovum present inside it.
Once the ovum comes out the ruptured follicle then transforms into corpus luteum. This is the luteal phase.
So, the correct answer is ‘mammals

Note: The corpus luteum is yellow in colour and is essential in maintaining pregnancy. If the fertilization takes place then the corpus luteum stays otherwise it breaks down.
This corpus luteum is very essential in pregnancy as it secretes progesterone which is important for the growing foetus.
The Graafian follicle is mostly visible on an ultrasound scan and is checked for any abnormalities.