Question 1

To best help it "sniff out" a fox, a hunting dog probably has a high concentration of

Accepted Answer

Chemoreceptors are specialized receptors in the nasal cavity that detect different smells. Hunting dogs have a highly developed sense of smell and rely on chemoreceptors to pick up scents of their prey. Mechanoreceptors in the ears detect vibrations, proprioreceptors are responsible for sensing body position and movement, and thermoreceptors in the front paws detect temperature. However, none of these are as important for a hunting dog's ability to detect a fox as chemoreceptors in the nasal cavity.

Question 2

In the middle ear, the three tiniest bones in the body receive the vibrations from the eardrum and transmit them to a second membrane, which channels them to the

Accepted Answer

The vibrations from the eardrum are received by the three tiniest bones in the body, which are the malleus, incus, and stapes. These bones transmit the vibrations to the oval window, which is a second membrane that channels them to the cochlea, where they are then converted into electrical signals that are sent to the brain. The eustachian tube connects the middle ear to the throat and is responsible for equalizing pressure in the middle ear. The pinna is the external part of the ear that collects sound waves and directs them into the ear canal. Therefore, the best choice is C, cochlea.

Question 3

A drug that inhibits the function of mechanoreceptors would affect your sense of

Accepted Answer

Mechanoreceptors are responsible for detecting touch sensations. Blocking their function would impair the ability to sense touch.

Question 4

The human ear is capable of detecting changes in pressure. The tiny hairs that detect this information are located in the

Accepted Answer

The cochlea is located in the inner ear and contains tiny hair cells called cilia that are responsible for detecting changes in pressure and translating them into electrical signals that the brain can interpret as sound. The ear canal, eardrum, and outer ear are all involved in transmitting sound waves to the cochlea, but it is the cochlea where the actual detection of pressure changes occurs.

Question 5

Researchers have suggested a fifth taste in humans known as umami and attribute the taste to the compound glutamate. Which of the following would support the belief that umami is a real "taste?"

Accepted Answer

The presence of chemoreceptors in taste buds that respond to glutamate would support the belief that umami is a distinct taste. The other options may be related to the interaction of glutamate with the body, but do not necessarily indicate the existence of a fifth taste.

Question 6

The figure below illustrates the organ of Corti, a part of the Cochlea in the human inner ear. 
What labeled region of this figure of the organ of Corti is directly stimulated to vibrate in response to the air movements causes by sound?

Accepted Answer

Region B, the basilar membrane, is directly stimulated to vibrate in response to the air movements caused by sound. This vibration then triggers the hair cells in the organ of Corti to generate neural signals that are sent to the brain for processing.

Question 7

In a single lens eye, the lens

Accepted Answer

In a single lens eye, the lens is responsible for focusing the light that enters the eye onto the retina, which then sends nerve impulses to the brain for visual processing. The lens does not control the amount of light entering the eye or screen out damaging ultraviolet light.

Question 8

Our overall perception of food depends on

Accepted Answer

Our overall perception of food depends on chemoreceptors (which detect taste and smell), photoreceptors (which influence our visual perception of food), and mechanoreceptors (which detect the texture and mouthfeel of food). Therefore, all of the above options are correct.

Question 9

The function of the pinna is to

Accepted Answer

The function of the pinna is to collect sound energy and enhance sound localization by reflecting and funneling the sound waves into the ear canal. It does not convert sound to nerve impulses, provide a sense of balance, or equalize pressure between the inner and middle ear.

Question 10

The pressure between our outer and middle ears is equalized by

Accepted Answer

The eustachian tubes connect the middle ear to the back of the throat, allowing air to flow in and out of the middle ear, thereby equalizing the pressure between the outer and middle ear. This is important for proper hearing and preventing damage to the eardrum.

Question 11

The sensory structures of animals all convert some property of the environment into

Accepted Answer

Sensory structures of animals convert some property of the environment into nerve impulses, which are then sent to the brain for interpretation and response. Chemicals and neurotransmitters may also be involved in the process, but the primary conversion is from environmental stimulus to nerve impulses. Pigments are not typically involved in sensory processing.

Question 12

A drug that decreases your ability to taste and smell might inhibit the function of

Accepted Answer

Chemoreceptors are responsible for detecting chemical stimuli, such as the taste and smell of substances. Therefore, a drug that decreases your ability to taste and smell may inhibit the function of chemoreceptors.

Question 13

Our sense of balance would not be possible without

Accepted Answer

Otoliths are small calcium carbonate crystals in our inner ear that move and stimulate hair cells, helping us sense changes in orientation and movement, and maintain our sense of balance. The other options, while also involved in hearing or balance, are not essential for our sense of balance.

Question 14

In our ears, sound is converted into nerve impulses by the

Accepted Answer

The organ of Corti is a structure in the cochlea of the inner ear that is responsible for converting sound waves into nerve impulses that can be processed by the brain. The eustachian tubes and auditory canal are part of the outer ear, and the eardrum is part of the middle ear, but none of these structures directly convert sound into nerve impulses. Therefore, the best choice is D, the organ of Corti.

Question 15

The eye is not like a camera in which of the following ways?

Accepted Answer

The eye focuses by changing the shape of the lens, not the distance between the lens and the surface that reacts to light.

Question 16

The thin membrane called the _______ receives sound waves that have moved into the ear and converts pressure changes into physical movement.

Accepted Answer

The eardrum (also known as the tympanic membrane) is a thin membrane that receives sound waves and converts them into physical movement, which is then transmitted to the inner ear. The cochlea is part of the inner ear and is responsible for processing sound signals. Hair cells are sensory receptors that line the inner ear and help transmit sound signals to the brain. Pheromones are chemical signals used for communication between organisms. Therefore, B is the best choice as it accurately describes the role of the eardrum in the process of hearing.

Question 17

Which of the following correctly explains what determines a given organism's sensitivity to a specific sensory input?

Accepted Answer

The sensitivity of an organism to a specific sensory input is determined by the number of sensory receptor cells it has that are sensitive to that particular feature of the environment. More receptor cells typically mean greater sensitivity.

Question 18

The human skin has numerous sensory receptors that take in information about our environment, and these receptors are concentrated in areas where detailed information on touch is needed. Which of the following body areas is likely to have the smallest number of sensory receptors?

Accepted Answer

The buttocks are an area of the body that does not require detailed information on touch, so it is likely to have the smallest number of sensory receptors compared to areas such as the fingertips, face, and feet which require more detailed sensory information.

Question 19

The function of otoliths in balance depends on

Accepted Answer

The otoliths are small crystals of calcium carbonate that are located in the inner ear. They are attached to the hair cells of the vestibular system, which is responsible for balance. When the head moves, the otoliths pull on the hair cells, which sends signals to the brain. The brain uses these signals to determine the position of the head and to maintain balance.

Question 20

Which of the following is not a sensory receptor?

Accepted Answer

There is no such thing as a "painireceptor." Proprioceptors detect body position and movement, nociceptors detect pain, and thermoreceptors detect temperature.

Quiz 26: Sensing the Environment