Pollen grain/microspore is a haploid, unicellular organism with a single nucleus that is non-motile. It is encircled by sporoderm, a two-layered wall. Exine refers to the outer wall, whereas intine refers to the interior wall.
The male reproductive whorl of the flower that produces male gametes is known as the androecium. The androecium, which consists of the anther and filament, is the stamen. Pollen sacs, which create pollen grains, are found in the anther.
The male gametophyte, which contains the male gametes, is represented by the pollen grain. Exine, which forms the outside layer, and intine, which forms the inner layer, surround the pollen particle. The two male gametes are formed when the generative cell divides. The vegetative cell is in charge of supplying nourishment. The pollen tube is formed when the intine layer emerges from the germ hole.
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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.