Human Respiratory System - Life Processes, Science Video Lecture - Class 10

in order to stay alive the body has to
breathe air we breathe in oxygen and we
breathe out carbon dioxide this process
is known as a respiration breathing
happens automatically every day the body
breathes about 20,000 times by the time
we reach 70 years old that's about 600
million breaths all this breathing
occurs because of the respiratory system
which includes the nose throat Voicebox
windpipe and lungs at the top of the
respiratory system the nostrils bring
air into the nose where it's filtered
warmed and moistened tiny hairs called
cilia protect the nasal passageways and
other parts of the respiratory tract and
filter out dust and other particles that
enter the nose through the breathe air
air can also be breathed in through the
mouth the two Airways of the nose and
mouth meet up at the pharynx which is
located at the back of the throat the
pharynx carries both food and air and is
used for digestion and respiration one
path is for food this is called the
esophagus which leads onto the stomach
the other side is for air it's called
the trachea a small flap of tissue
called the epiglottis covers the air
only passage when we swallow this stops
food and liquid from going into the
lungs the larynx or voice box is located
at the top of the trachea the air only
pipe this is where our vocal cords are
the trachea or windpipe which is a two
to three centimeter tube then extends
downwards from the bottom of the larynx
for about 12 centimeters the walls of
the windpipe are made strong by stiff
rings of cartilage that keep it open the
trachea is also lined with tiny hairs
they sweep foreign particles and fluids
out of the airway keeping them from
entering the lungs the windpipe divides
into two branches and each one of these
enters one of the two lungs of the body
each branch resembles the limbs of a
tree dividing into smaller finer
branches called bronchioles the
bronchioles end in tiny air sacs called
alveoli which look a bit like grapes
these structures enable fresh air to get
to the air sacs which are surrounded by
tiny blood vessels or capillaries the
oxygen passes through these air sacs and
travels through the capillary walls into
the bloodstream at the same time
carbon dioxide transfers from the
bloodstream into the air sacs where it
gets breathed out of the body when we
exercise the body needs more oxygen to
feed the muscles as they work harder the
body responds by breathing more quickly
and deeply as the cells of the muscles
use up more oxygen the lungs have to
work harder to keep up the supply the
respiratory system then speeds up to
supply the body with much needed oxygen
and also to get rid of the carbon
dioxide waste in the system over time
exercising also helps our chest cavity
to get bigger which enables the body to
increase the amount of air it takes in
more capillaries form around the air
sacs so the body gets better at swapping
oxygen and carbon dioxide gases we can
see how the body's respiratory system
helps the body to move about and is
influenced by regular and ongoing
physical activity as well