Receptor Organs in Man

Receptor Organs in Man

Introduction
When it is threatening to rain, you see lightening and hear the thunder Which i sometimes scary. How do you think you are able to see and hear? What cause: you to get scared?
In this chapter, you will appreciate that sensory organs detect stimuli and enable the body to respond and function properly.
6.1: The Sensory Organs in Man
In primary science, you learnt about human sensory organs like the eye, the ear, the skin, the nose and the tongue. The organs are referred to as receptor organs. In this section, you will understand the roles and functions of the human eye and the ear and their functions.

The eye

The eye performs its functions by responding to light stimuli. In Activity 6.1, you will identify the features of a human eye.

Activity 6.1: Identifying the parts of a human eye and their functions Do this activity in a pair.
Key question: What are the external parts of the eye?
What you need: Reference materials about the human eye, a notebook, a pen and a pencil
What to do:

1. Keenly look at your partner’s eye and using your primary science knowledge, draw and label it. In your own words describe the parts.
2. Discuss the functions of the external parts that you have drawn.
3. Using reference materials or the Internet, draw and name the labeled parts in the figure below.

Observe the cross section of the human eye below and use reference materials to label the different parts.

Research from reference materials about the functions of the parts of the eye and fill the table below.

6. Discuss the major roles of an eye to a human being?
7. How can eyes be cared forto keep then functioning properly. present your work to the rest of the class for discussion

Present your work to the rest of the class for discussion

Eye Defects
Jane sits at a front chair in the class. She complains that she cannot read properly what the teacher writes on the blackboard. Jacob was watching a game at the pitch. He says that he could see the ball at the far goal post but could not see it properly at the near goal post. What eye defects do you think
these two have?
Eye defects happen when there are structural changes of the eye that make the focusing mechanism difficult. These changes usually affect the lens failing them to form a sharp image on the retina.
In Activity 6.2, you will explore long and shortsightedness as major eye defects.

Activity 6.2: Interviewing a professional on how long and short sightedness can be detected and corrected
Do this activity in a group.
Key question: How can you detect and correct long and short sightedness?
What you need: A resource person, reference materials about eye defects, a notebook, pen, a questionnaire
What to do:

1. Visit the school sickbay and interview the nurse about:
   i) How long and short sightedness eye defects occur and how they can be detected.
   ii) How long and short sightedness can be corrected.

i) What is happening in picture A and Picture B? Explain your observation in regards to eye defects.
ii)Research and draw diagrams to show what is happening in the
eyes of the person in A and B above.
iii)Using your findings from the interview, demonstrate how you think these people can be helped so that they can read normally?

3. Research and make notes about other eye defects and diseases and how they can be controlled.
   share our work with another group.

The Ear
When the bell goes, you hear the sound. How do you think you get that sound? The ear, see Fig 6.1 performs its functions by responding to sound stimuli. In Activity 6.3, you will identify the external features of a human ear.

Activity 6.3: Identifying parts of the ear and stating their functions Do this activity in a pair.
Key question: Mention the parts of the ear and state their functions
What you need: A pencil, a notebook, reference materials about the ear, the Internet

What to do:

1. Keenly look at your partner’s ear. Draw it and using your primary science knowledge, label it. In your own words, describe the parts.
2. Discuss the functions of the external features that you have drawn
3. Using the Biology textbook and or the Internet, name the parts labeled A-M of Figure 6.1.
4. Research about the functions of the parts of the ear labeled above and able below.

5. What other roles does the human ears play on the body?
6. How can the ears be maintained to keep it functioning properly.
   compare your responses with those of another pair.
   •self Study: Using the Internet, research about the role played by the Central Nervous System in seeing and hearing.

In this chapter, you have learnt that:

1. The human sensory organs are also know as receptor organs. They are the eye, ear, nose, skin and the tongue.
2. Short and long sightedness are eye defects that happen when there are structural changes of the eye that makes the
   focusing mechanism difficult by making the lens fail to form a sharp image on the retina.
3. The ear functions by responding to sound stimuli.

You can ask the super AI Biology Teacher below questions of S1-S4 biology and get answers