The document discusses the human body's sensory and response systems. It describes the different types of stimuli the body receives, both internal and external. It also outlines the main sensory organs - eyes, ears, skin, nose, tongue - and how each receives different types of stimuli via specialized receptors. Finally, it provides an overview of the central nervous system, including the brain, spinal cord, sensory and motor nerves, and neurons, and how these systems work together to coordinate the body's responses to stimuli.

1. Sensitivity and
Coordination
By Paula Crespo González

2.  A stimulus is anything that affects any of the
body’s activities. There are two types of
stimuli:
 Internal
 External
 A response is the body’s answer to a stimulus.

3.  The body has different receptors to receive different
types of stimuli:
▪ Internal Receptors
▪ External Receptors

4.  The body responds to any stimulus
▪ Muscular responses
▪ Glandular responses

6.  The organ of the sense is the eye. The main part of
the eye is the eyeball.
 Parts of the eye: Cornea, Pupil, Iris, Lens, Retina and
the Optic Nerve.

7.  The ear is the body’s organ for the sense of hearning. The ear
has three parts:
▪ The Outer Ear: It is made up of the ear and outer
auditory canal.
▪ The Middle Ear: It is made up of the eardrum and a chain
of small bones.
▪ The Inner Ear: It is made up of the cochlea and the
auditory nerve.

8.  The body’s for the sense of touch is the skin
 Epidermis: It is the outer layer.
 Dermis: It is under the epidermis.
 Hypodermis: It is under the dermis.

9.  The body’s organ of the smell is the nose. The
receptor of smell are in the pituitary, a
structure inside the nostrils.

10.  The body’s organ for the sense of taste is the
tongue. The receptors of smell are in the
taste buds.

12.  Brain: It is inside the skull.
 Spinal Cord: It is a thick cord made up of
many neurons that goes through the inside of
the spine.

13.  Sensory nerves: They transmit information from the
sensory organs and internal organs to the central
nervous system.
 Motor nerves: They transmit responses from the
central nervous system to the muscles and glands of
our bodies.

14.  Neurons are the cell that belong to the nervous
system. They have a star-like shape made up of
three parts: a cell body, dentrites and axons.