This document discusses the human body's sensory and response systems. It describes the different types of stimuli, receptors, and responses. The five senses are explained, including the organs and processes involved in sight, smell, hearing, touch, and taste. The nervous system and its role in transmitting sensory information to the brain and motor responses is outlined. Voluntary and involuntary movements are distinguished. Finally, the skeletal and muscular systems are introduced as the structures responsible for carrying out muscular responses directed by the nervous system.

1. Unit 2 sensitivity and
coordination
Maria boizas

2. Stimuli
A stimulus is anything you
see,hear,touch,smell or taste.
 There are two types of stimuli:
 Internalstimuli
 External stimuli

3. The smell of a flower is an external
stimuli.

4. receptors
 Thereare two types of receptors:
Internal receptors
External receptors

5. Responses
A response is the body’s answer to a
stimulus
 There are two different types of
responses:
 Muscular responses
 Glandular responses

6. Chewing is a muscular response

7. The senses

8. sight
 The eye is the organ of sight.
it is made up of the eyeball and
protected by the eyebrows,eyelids
and eye lashes.

9. Process of sight
 First light goes through the cornea.
 Then light passes through the pupil,the
opening of the iris.
 After that light passes through the lens
with focuses the image on the retina.
 The information in the retina travels to
the brain through the optic nerve

10. smell
 Thenose is the organ of smell.The
receptorsof smell are in the pituitary
gland,inside the nostrils.

11. hearing
 The ear is the organ os hearing.
 It has three parts:
 The outer ear
 The middle ear
 The inner ear

12. The process of hearing
 First the outer ear receives sounds
 Then the middle ear changes sounds
into vibrations.
 Finally the inner ear changes vibrations
into nerve impulses that go to the brain

13. touch
 The skin is the organ of touch.
 It is made up of three layers:
 Epidermis
 Dermis
 Hypodermis

14. taste
 The tongue is the organ of taste.
 The receptors of taste are in the taste
buds.
 There are taste buds all around the
tongue.

15. The nervous system
The nervous system is made up of
nerve centres and nerves.

16.  The
peripheral nervous system is
made up of:
 Sensory nerves
 Motor nerves
 The central nervous system has two
parts:
 The brain
 The spinal cord

18. neurons
 They are made up of a cell body,dendrites
and axons.
 Neurons receive information from other
neurons.

19. Voluntary and involuntary
movements
 Ourbodies react to stimuli making
voluntary or involuntary movements.

20. Voluntary movements
 When we see the clouds our sensory
nerves inform the brain about this.
 Our brain processes the information and
produces a response.
 Our motor nerves transmit a response to
the muscles.

21. Involuntary movements
 The spinal cord produces a response in
the case of involuntary movements.
 Sensory nerves transmit information about
involuntary movements to the spinal cord.
 The spinal cord produces a very fast
response.

22. The skeletal system
 Theskeletal and muscular system is in
charge of carrying muscular responses
created by the nervous system.it is
made up of the skeleton and the
musculature.

23. The skeleton
 The skeleton is made up of all the bones
in the body.
 Head bones:skull bones and facial bones.
 Trunk bones:spine and rib cage.
 Limb bones:there are two groups the upper
limb bones and the lower limb bones.

25. joints
 The joints are located where two or more
bones meet.Bones are connected by
ligaments.
 There are three types of joints:
 Moveable joints
 Semi-moveable joints
 Fixed joints

27. The musculature
 The musculature is the set of muscles in the
body.locomotor muscles are conected to the
bones.when they contract or relax,they move the
bones.
 Head muscles:masseter,buccinator and orbicular.
 Trunk muscles:sternocleidomastoid,abdominal,
pectoral,intercostal and trapezius.
 Limb muscles:biceps,triceps,deltoid,quadriceps,
gluteus and calf muscles.
.

28. The end