Interaction is how humans interact with the environment. We perceive
the world through our senses. Sight, touch, smell, hearing and taste
allow us to explore the environment around us.
BUT, WHAT IS INTERACTION?
All the information received by our senses is processed
by our most important organ, the brain. The brain is
home to the conscious and unconscious mind, as well
as our emotions and memory.
It controls our involuntary actions, such as breathing, or digesting our food, as well
as our thinking and decision making.
What other types of involuntary actions do we have?
Which actions are receiving information or
giving a response? Maybe some can be both!
Living organisms are made of cells.
Cells that perform the same function
together are called tissue.
Tissue groups are called organs.
Organs work together and form systems
which make up the bodies of organisms.
One of these systems is the nervous system.
The brain sends messages to all
different parts of the nervous system,
such as the locomotor system
(or musculoskeletal system).
The locomotor system allows us to
respond to the stimuli from our senses and
controls our internal systems, such as the
digestive system or the respiratory system.
The Central Nervous
• The brain and the spinal cord make
the central nervous system.
• spinal cord
The Brain https://www.youtube.com/watch?v=Qw8E9WnZTQk
The brain controls our nervous
system and is protected by the
The brain is made up of three
main parts: cerebrum,
cerebellum and the brain
The cerebrum is the
biggest part of the
brain. Here we
from our senses and
we do our cognitive
There are 2 main
hemispheres: the left
hemisphere and the
CEREBELLUM The cerebellum controls our
The brain stem is the continuation of
the spinal cord. It controls involuntary
actions, such as our heartbeat,
breathing and sleeping.
The spinal cord is made up of nerve tissue
and runs from our brain down our spine.
The spinal cord is protected by the
vertebrae. It controls our reflex actions.
Peripheral Nervous System
The peripheral nervous system is made up
of nerves. Nerves are made up of tiny cells
called neurons that transfer information
through the nervous system using electrical
and chemical signals. Different neurons carry
out different tasks.
Light reflected from an object enters
our eyes through the cornea and pupil.
The amount of light entering our eyes is
controlled by the iris. The iris gives the
eye its colour.
The lens focuses the light on the retina
at the back of the eye.
Nerve receptors in the retina transmit
the information to
the optic nerve which then sends
the information to the brain.
The place where the optic nerve leaves
the eye is called a blind spot. This area
does not respond to light.
• Sound waves enter the auditory
canal in the outer ear and cause
the eardrum to vibrate.
• In turn, these vibrations make
the three small bones in the
middle ear vibrate.
• The vibrations eventually reach
the cochlea in the inner ear,
where they become electrical
• The auditory nerve then sends
the signals to the brain for
3 small bones
Chemicals in the air enter our nose through
our nostrils. The chemicals then come into
contact with nerve receptors which send
the information to the brain via
the olfactory nerve.
Substances enter our mouth and come
into contact with our tongue. The tongue is
covered in taste buds which have receptor
cells. These receptor cells detect the
different tastes (salty, sweet, bitter and
sour) and send the information to the brain.
Chemicals from substances in our mouths
also enter the nose which is why if we have
a blocked nose, food often tastes different
The skin covers and protects
our whole body. The middle
layer of skin, called the dermis,
contains nerves and blood
vessels. These detect sensations
such as heat, pressure and
The nerves in the skin send
information to the brain
through the peripheral nervous
system and the spinal cord.
Our body moves in response to signal from
These signals travel through the nervous
system to our muscles.
Our muscles contract allowing us to move,
hold objects, kick balls and make other
The muscles are supported by the skeleton
and the joints.
The whole system is called the locomotor or
The skeleton is made up of bones. There are three types of
Short bones: such as the vertebrae in the spine, provide support
Flat bones: such as ribs and the pelvis, protect the internal
Long bones: shape limbs and are used for movement.
Our bones are connected at the joints by strong elastic tissue
called ligaments. The ends of the bones at the joints are covered
in strong, flexible tissue called cartilage. There are three types of
Fixed joints do not move. The parts of the skull are connected
by fixed joints.
Semi-flexible joints, such as the vertebrae in the spine, only
allow a small amount of movement.
Most joints in the body are flexible joints which are important