The Human Body II

1. The Human Body II Presentation made by students of 6º

2. Sight The eye is the organ used for sight. Light enters the eye through the pupil. The iris contracts or dilates to regulate the amount of light our eyes need. Then, light crosses the lens and reaches the retina. The retina transmits the information to the brain trough the optic nerve.

3. The parts of the eye • Sclera: protects the inner parts of the eye. • Conjunctiva: covers the sclera. • Cornea: protects the eye from the exterior. • Choroid: layer located between the sclera and the retina. Yaiza and Iván

4. The sense of smell Thesense of smellisthesensethatwe use tosmell. It’sfound in the nasal cavity, insideournose.

5. There are approximately 10 million sensory receptors cells in our nose.When a smell enters our nose these cells gather information and send a message to our brain.

6. The sense of taste The sense of taste is located in our tongue. The tongue is a muscular organ with about 3000 taste buds. Taste buds transmit sensations of taste.

7. We can distinguish four flavours: sweet, sour, salty and bitter.

8. The Sense of Hearing The sense of hearing is located in our ears. The outer ear collects the sounds and transmits these vibrations to the eardrum.Then,in the middle ear,the vibrations pass on to the hammer stirrup and anvil.They carry these vibrations to the inner ear.Sound passes into the cochlea and finally to the brain through the auditory nerve Victor and Arianne

9. The Parts of the Ear • The outer ear,the middle ear and the inner ear are the three main parts of the ear. • There are three tiny bones called hammer,stirrup and anvil. • We also have the eardrum and the auditory nerve in our ear.

10. The sense of touch by Laura. B The sense of the touch is located in our skin. The skin has two parts: epidermis and dermis. The top part of the skin is called epidermis and the inner part of the is calleddermis.

11. Touch detectors • Touch detectores are located in our epidermis. They send information to the brain. The brain can interpret many different kinds of sensations. They include temperature, texture, shapes and sizes.

12. The nervous system Our body has a system that controls all of the information and the responses. This system is called the nervous system. The central nervous system formed by the encephalon and spinal cord

13. The peripheral nervous system The peripheral nervous system covers our whole body and is formed by the nerves

14. Theperipheral and central nervoussystem • The central nervous system and the peripheral nervous system continuously transmit information and orders to each other.

15. The skeleton All the bones and cartilages in our body form the skeleton. The skeleton is made up of 206 bones. Our bones are hard and rigid. Our skeleton and cartilage grow with us.

16. The head and the limbs • In the head we have the skull that has many different parts.

17. In the arms and legs we have lots of bones

18. Muscles Muscles are made of tissue. They can contract or relax. Muscles are important because they produce movement. Some muscles are attached to bones by tendons. When we move a muscle we also move the bone.

19. Voluntary or involuntary • Muscles can be voluntary, like the biceps and the masseter, or involuntary, like the muscles in the heart or the stomach. There are more than 600 muscles in our body.

20. Muscles work • When muscles work they need more energy and oxygen , so they receive more blood than when they are resting . Pairs of muscles work against each other. One muscle contracts while the other one relaxes. For example, when the biceps contracts the triceps relaxes.