Describe the process of development of an ovum from an oogonium in human female.
Answer: The formation of an ovum from oogonium is known as oogenesis. Multiplication, growth, and maturation are the three stages.
Oogenesis begins in the female foetus’ embryonic ovaries.
The cell begins to divide (oogonia) and enters prophase 1 of the meiotic cycle, when it is momentarily arrested and referred to as a primary oocyte.
A layer of granulosa cells surrounds each primary oocyte, forming a primary follicle. Many of them degenerate, leaving only 60000 to 80000 primary follicles by puberty.
It is then encircled by more granulosa layers and a new theca, forming a secondary follicle.
These develop into the tertiary follicle, which is distinguished by the presence of a fluid-filled cavity known as the Antrum. The primary oocyte matures and completes its first meiotic division at this stage.
The asymmetrical division results in the development of a big secondary oocyte and a small polar body. The secondary oocyte produces a new layer called Zona pellucida around itself when the tertiary follicle matures into a Graafian follicle. This follicle ruptures during ovulation to release a secondary oocyte/ovum (which completes 2nd meiotic division just prior to fertilization)
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west of the geographic north. The north tip of the magnetic needle of a dip circle placed in the plane of magnetic meridian points above the horizontal. The horizontal component of the earth’s field is measured to be 
Specify the direction and magnitude of the earth’s field at the location.At a certain location in Africa, a compass points 
and 
carrying currents of 
and 
in the same direction are separated by a distance of 
. Estimate the force on a 
section of wire A.
wire carrying a current of 
is placed inside a solenoid perpendicular to its axis. The magnetic field inside the solenoid is given to be 
. What is the magnetic force on the wire?
and making an angle of 
with the direction of a uniform magnetic field of 
. What is the magnitude of the field 
at a point 
from the wire?
-turns carrying current 
.
is at distance 
from the wire. Find the force acting on the electron if its velocity is directed towards the wire.