1.
Our Ears
Description
Our ears allow us to hear sounds of all types: the voices of our family and friends, the music we like, the sounds of nature, the noises of the city. As well, our ears help us to keep our balance and warn us of danger.
The part of our head that we call the ear is only the outer part of the organ of hearing. The ear has three parts. Sound passes through the outer ear to the middle ear, which picks up the vibrations of the sound and transfers it to the inner ear. Here they are changed into nerve signals that travel to the brain. The brain translates the nerve signals and tells us what sound we are hearing.
We measure sound in decibels. The sound of this page turning might be about thirty (30) decibels. While the concert your big sister attended last night could have measured an ear-splitting one hundred (100) decibels!
Our inner ear helps us to keep our balance. It has a number of semicircular canals that contain fluid, and this fluid moves when we move. Information about the fluid's movement is carried to the brain by nerves. The brain makes sense of this information and then sends messages to the muscles we need to keep our balance.
Have you noticed that a cat can move its ears and point them towards a sound? This is because a cat must be constantly on-guard against danger and needs to know the direction from which a sound comes. Our ears don't move in the same way. Can you think why? It is because we don't need to protect ourselves in the same way. So, our ears can sit close to our heads and not move all around.
True or False?
Our ears pick up sound vibrations.
Correct Answer
A. True
Explanation
Our ears pick up sound vibrations. This is true because the middle ear picks up the vibrations of sound and transfers them to the inner ear. In the inner ear, these vibrations are changed into nerve signals that travel to the brain, allowing us to hear and interpret sounds.
2.
The middle ear changes nerve signals into vibrations?
Correct Answer
B. False
Explanation
The middle ear does not change nerve signals into vibrations. Instead, it acts as a bridge between the outer ear and the inner ear, transmitting sound vibrations from the eardrum to the inner ear. The inner ear is responsible for converting these vibrations into nerve signals that can be interpreted by the brain. Therefore, the correct answer is false.
3.
We measure sound in vibrations?
Correct Answer
B. False
Explanation
Sound is not measured in vibrations. Sound is measured in units of frequency, such as hertz (Hz), which represents the number of vibrations per second. Vibrations are the physical phenomenon that creates sound, but the measurement of sound itself is done in terms of frequency. Therefore, the statement that we measure sound in vibrations is incorrect.
4.
Loud music might measure one hundred (100) decibels?
Correct Answer
A. True
Explanation
Loud music can indeed measure one hundred decibels. Decibels are a unit used to measure the intensity or loudness of sound. A decibel level of 100 is considered very loud and can cause damage to the ears if exposed to for a prolonged period of time. Therefore, the statement is true.
5.
A cat moves its ears in order to hear better?
Correct Answer
B. False
Explanation
Cats move their ears not to hear better, but to locate the source of a sound more accurately. Their ears have the ability to rotate and move independently, allowing them to pinpoint the direction from which a sound is coming. This helps them in hunting and being aware of their surroundings. Therefore, the statement that cats move their ears in order to hear better is false.
6.
Our outer ear has fluid filled canals?
Correct Answer
B. False
Explanation
The statement is false because our outer ear does not have fluid-filled canals. The outer ear consists of the pinna and the ear canal, which are both made of cartilage and skin. The fluid-filled canals are actually part of the inner ear, specifically the cochlea, which is responsible for converting sound vibrations into electrical signals that can be interpreted by the brain.
7.
Wiggling our ears helps us hear move efficiently?
Correct Answer
B. False
Explanation
Wiggling our ears does not help us hear more efficiently. The ability to wiggle our ears is a vestigial trait, meaning it is a remnant of our evolutionary past and does not serve a functional purpose in modern humans. Our ears are designed to capture sound waves and transmit them to our brain for processing, and wiggling our ears does not enhance this process in any way. Therefore, the statement is false.
8.
What does the middle ear do?
Correct Answer
B. Picks up vibrations and transfers them to the inner ear
Explanation
The middle ear picks up vibrations and transfers them to the inner ear. The middle ear consists of three small bones called the ossicles (malleus, incus, and stapes) that amplify and transmit sound vibrations from the eardrum to the inner ear. These vibrations are then converted into electrical signals by the inner ear and sent to the brain for processing. The middle ear plays a crucial role in the process of hearing by transmitting sound waves effectively from the outer ear to the inner ear.
9.
How does our inner ear help keep our balance?
Correct Answer
D. Has fluid filled canals that keep level
Explanation
The inner ear helps keep our balance by having fluid-filled canals that stay level. These canals contain sensory cells with tiny hairs that detect the movement of the fluid when we change positions. This information is then sent to the brain, which helps us maintain our balance.
10.
Find the word in the text that has the same meaning as:
(clue: the first letter is provided)
* harm = d__________
Correct Answer
danger
Danger
Explanation
The word "danger" has the same meaning as "harm" as it refers to a situation or condition that poses a risk or threat to someone's well-being or safety. The first letter "d" matches with the word "danger" in the answer options.
11.
Find the word in the text that has the same meaning as:
(clue: the first letter is provided)
* moves = t__________
Correct Answer
tranfers
tranfer
travel
travels
Transfer
Travel
Explanation
The word "moves" refers to actions or activities that involve changing one's position or location. The word "transfers" has a similar meaning as it also involves moving from one place to another. Similarly, "travel" and "travels" also refer to the act of moving or going from one place to another. "Transfer" and "Travel" are also synonyms for "moves" as they indicate the action of changing position or location.
12.
Find the word in the text that has the same meaning as:
(clue: the first letter is provided)
* quivers = v__________
Correct Answer
vibrates
Vibrates
Explanation
The word "quivers" means to shake or tremble. The word that has the same meaning and starts with the letter "v" is "vibrates".
13.
Find the word in the text that has the same meaning as:
(clue: the first letter is provided)
* always = c__________
Correct Answer
constant
constantly
Constantly
Constant
Explanation
The word that has the same meaning as "always" and starts with the letter "c" is "constant". "Constant" means something that remains the same or continues without change. It can also be used to describe something that is consistent or unchanging. "Constantly" and "Constantly" are variations of the word "constant" and have the same meaning.
14.
Find the word in the text that has the same meaning as:
(clue: the first letter is provided)
* keep safe = p__________
Correct Answer
protect
Protect
Protects
protects
Explanation
The word in the text that has the same meaning as "keep safe" is "protect".