1.
Psychology arose in the 19th century from developments in a number of areas, primarily:
Correct Answer
D. Science and pHilosopHy
Explanation
Psychology emerged in the 19th century as a result of advancements in both science and philosophy. Scientific methods and principles were being applied to understand human behavior and mental processes, leading to the establishment of psychology as a scientific discipline. At the same time, philosophers were also exploring questions related to the mind, consciousness, and human nature, which contributed to the development of psychological theories and concepts. The combination of scientific inquiry and philosophical reflection played a crucial role in the formation and growth of psychology as a field of study.
2.
Structuralism is to ______ as functionalism is to ____________.
Correct Answer
C. Elements of consciousness; purpose of consciousness
Explanation
Structuralism and functionalism are two different approaches in psychology. Structuralism focuses on analyzing the different elements of consciousness, while functionalism focuses on understanding the purpose and function of consciousness. Therefore, the correct answer is "elements of consciousness; purpose of consciousness."
3.
Psychology is most closely related to:
Correct Answer
A. Biology
Explanation
Psychology is most closely related to biology because both fields study the human mind and behavior. Biology explores the biological basis of behavior, including the brain, genetics, and hormones, while psychology focuses on understanding and explaining human thoughts, emotions, and actions. The two disciplines often intersect, as psychological processes are influenced by biological factors. For example, studying how neurotransmitters affect mood and behavior is a common area of research in both fields. Understanding the biological foundations of psychology is crucial for comprehending human behavior and mental processes.
4.
Rationalism is to ___________ as empiricism is to _____________.
Correct Answer
B. Logic; observation
Explanation
Rationalism is a philosophical belief that knowledge is primarily acquired through reason and logical thinking. Similarly, empiricism is the belief that knowledge is primarily acquired through sensory experience and observation. Therefore, the correct answer is "logic; observation" because it accurately pairs the concepts of rationalism and empiricism with their respective methods of acquiring knowledge.
5.
Through their research on human responses to physical stimuli, both von Helmholtz and Fechner contributed to the beginnings of:
Correct Answer
D. PsychopHysics
Explanation
Von Helmholtz and Fechner's research on human responses to physical stimuli laid the groundwork for psychophysics. Psychophysics is the branch of psychology that studies the relationship between physical stimuli and the sensations and perceptions they produce. By examining how humans perceive and respond to different stimuli, von Helmholtz and Fechner helped establish the field of psychophysics, which continues to explore the complex relationship between the physical world and our subjective experiences.
6.
Suppose that you conduct an experiment to study the effects of love on improving children's self concepts. To manipulate love, you allow a research assistant to hug each child after he/she has successfully completed a set of math problems. After the study is over, you ask the children if they felt loved during the study. They all say no. Apparently, your operational definition of your independent variable is:
Correct Answer
C. Invalid
Explanation
The operational definition of the independent variable, which is manipulating love by allowing a research assistant to hug each child after completing math problems, is invalid because it does not accurately measure or represent the concept of love. The fact that all the children reported not feeling loved suggests that the operational definition did not effectively capture the intended variable. Therefore, the operational definition is considered invalid in this scenario.
7.
In psychological research, the term generalization refers to:
Correct Answer
D. Concluding that the results obtained from a sample can also be applied to the larger population
Explanation
The term generalization in psychological research refers to the process of applying the results obtained from a sample to the larger population. This means that researchers can draw conclusions about the entire population based on the findings from a smaller group. Generalization allows researchers to make broader statements and predictions about human behavior and psychological processes. It is an important aspect of research as it helps to establish the external validity and generalizability of the findings.
8.
Minor deception may be permitted in research providing there is ___________ and _____________.
Correct Answer
A. No forseeable harm; there is a full debriefing
Explanation
Minor deception may be permitted in research providing there is no foreseeable harm and there is a full debriefing. This means that if the deception used in the research study does not pose any potential harm to the participants and if they are provided with a thorough explanation and discussion of the study after their participation, then it may be considered acceptable. This ensures that participants are not negatively affected by the deception and are fully informed about the purpose and procedures of the study.
9.
The first step of the scientific method specifies that a researcher:
Correct Answer
B. Formulate a hypothesis
Explanation
The first step of the scientific method is to formulate a hypothesis. This involves identifying a specific question or problem that the researcher wants to investigate and then proposing a possible explanation or prediction for that question or problem. By formulating a hypothesis, the researcher is able to guide their study and design experiments or collect data that will help them test and evaluate the validity of their hypothesis. This step is crucial as it sets the foundation for the entire scientific research process.
10.
A researcher has 2 groups of subjects - one that has been taught a memory aid, and another that has not. Both groups are then asked to learn a list of 20 nouns in 2 minutes, and both are then given a recall test. What is the independent variable?
Correct Answer
C. Whether or not the participants have been taught the memory aid
Explanation
The independent variable in this experiment is whether or not the participants have been taught the memory aid. This is the variable that the researcher manipulates in order to determine its effect on the participants' performance on the recall test. The researcher is interested in examining whether teaching the memory aid has an impact on the participants' ability to recall the list of 20 nouns.
11.
Mean is to ____________ as standard deviation is to _____________.
Correct Answer
A. Central tendency; variability
Explanation
The mean is a measure of central tendency, representing the average value of a set of data. Similarly, the standard deviation is a measure of variability, indicating how spread out the data points are from the mean. Therefore, the relationship between mean and standard deviation can be described as central tendency and variability.
12.
An organism's phenotype is the result of:
Correct Answer
D. The interaction of its genotype with the environment
Explanation
An organism's phenotype is the observable characteristics or traits that are determined by both its genotype (genetic makeup) and the environment it interacts with. While the genotype provides the genetic instructions, the environment plays a crucial role in how those genes are expressed. Environmental factors such as nutrition, temperature, and social interactions can influence the development and expression of certain traits. Therefore, the interaction between an organism's genotype and the environment is what ultimately shapes its phenotype.
13.
The fact that male peacocks have evolved large tail feathers (even though large feathers appear to be an impediment for survival) is best explained by:
Correct Answer
B. Evolution through sexual selection
Explanation
The evolution of large tail feathers in male peacocks can be best explained by evolution through sexual selection. This theory suggests that certain traits evolve because they increase an individual's chances of mating and reproducing, even if they may have negative effects on survival. In the case of peacocks, the large and colorful tail feathers are attractive to females and play a crucial role in mate selection. Therefore, over time, males with larger and more elaborate tail feathers have a higher chance of mating and passing on their genes, leading to the evolution of this trait.
14.
Concordance is the degree to which two people:
Correct Answer
C. Share the same pHenotype
Explanation
Concordance refers to the degree to which two people share the same phenotype. Phenotype refers to the observable characteristics or traits of an individual, such as physical appearance or behavior. Therefore, when two people share the same phenotype, it means that they have similar observable characteristics or traits. This could be due to a variety of factors, including genetic similarities, environmental influences, or a combination of both.
15.
Natural selection has favoured species that reproduce sexually because sexual reproduction:
Correct Answer
D. Leads to genetic diversity, which is adaptive
Explanation
Sexual reproduction leads to genetic diversity, which is adaptive. This is because sexual reproduction involves the exchange and recombination of genetic material between two parents, resulting in offspring that have a combination of traits from both parents. This genetic diversity allows for a greater range of variation within a population, which can be beneficial for survival and adaptation to changing environments. It increases the chances of some individuals having traits that are advantageous in certain conditions, ensuring the survival of the species as a whole.
16.
Which of the following statements is FALSE regarding human sexual behaviour?
Correct Answer
A. Unmarried women tend to seek casual sexual relationships
Explanation
The statement "Unmarried women tend to seek casual sexual relationships" is false. Research suggests that both men and women, regardless of marital status, have similar desires for casual sexual relationships. The idea that unmarried women are more likely to seek casual sexual relationships is a stereotype that is not supported by empirical evidence.
17.
Extinction would happen most rapidly following which reinforcement schedule?
Correct Answer
D. Fixed-ratio, every response is reinforced
Explanation
Extinction refers to the process of eliminating a learned behavior when the reinforcement is no longer provided. In the case of the given question, the fixed-ratio schedule, where every response is reinforced, would lead to the most rapid extinction. This is because the individual becomes accustomed to receiving reinforcement after every response, and when the reinforcement is suddenly removed, the behavior quickly diminishes. In contrast, variable-ratio schedules and fixed-interval schedules tend to result in slower extinction because the reinforcement is not as predictable or consistent, making it more difficult for the individual to learn that the behavior is no longer being reinforced.
18.
__________ is a learning procedure that utilizes reinforcement to guide a response in closer and closer approximations to a desired behaviour.
Correct Answer
B. Shaping
Explanation
Shaping is a learning procedure that utilizes reinforcement to guide a response in closer and closer approximations to a desired behavior. This means that instead of waiting for the desired behavior to occur naturally, shaping involves reinforcing small steps or behaviors that are similar to the desired behavior, gradually shaping the individual towards the desired behavior. Through this process, the individual learns and develops the desired behavior through reinforcement and repetition.
19.
Which schedule of reinforcement is most similar to that used in gambling?
Correct Answer
B. Variable-ratio
Explanation
The variable-ratio schedule of reinforcement is most similar to that used in gambling because it involves providing reinforcement after a varying number of responses. In gambling, the reinforcement (winning) is unpredictable and can occur after a different number of attempts or bets. This creates a high level of motivation and persistence in both gambling and the variable-ratio schedule, as individuals are unsure when they will receive the reinforcement but are motivated to keep trying in the hopes of a reward.
20.
Which of the following presents the most convincing evidence that an animal has learned by "insight" rather than by trial and error?
Correct Answer
D. A transfer of training occurs
Explanation
A transfer of training occurs when an animal is able to apply what it has learned in one situation to a new and different situation. This suggests that the animal has gained a deeper understanding or insight into the problem, rather than simply relying on trial and error. This is because trial and error learning typically involves a more gradual learning curve and does not necessarily result in the ability to transfer knowledge to new situations.
21.
To what is the tendency of the conditioned stimulus (CS) to elicit a conditioned response (CR) related?
Correct Answer
B. The number of CS-US pairings
Explanation
The tendency of the conditioned stimulus (CS) to elicit a conditioned response (CR) is related to the number of CS-US pairings. The more times the CS and the unconditioned stimulus (US) are paired together, the stronger the association between them becomes. This strengthens the conditioned response, leading to a higher tendency for the CS to elicit the CR.
22.
Which of the following structures, located in the middle of the brain, is often described as being the relay station that connects various parts of the brain?
Correct Answer
D. The thalamus
Explanation
The thalamus is often described as the relay station that connects various parts of the brain. It is a small structure located in the middle of the brain and plays a crucial role in relaying sensory and motor signals to different parts of the cerebral cortex. It acts as a gateway, receiving information from sensory organs and relaying it to the appropriate areas of the brain for processing. Additionally, the thalamus is involved in regulating consciousness, sleep, and alertness.
23.
In split-brain studies, when a picture of a common object was flashed to the left visual field, the patient would be unable to ___________ but would be able to ______________.
Correct Answer
A. Identify it verbally; identify it by touch with the left hand
Explanation
In split-brain studies, when a picture of a common object was flashed to the left visual field, the patient would be unable to identify it verbally but would be able to identify it by touch with the left hand. This suggests that the left visual field is processed by the right hemisphere of the brain, which is responsible for touch sensations on the left side of the body. The inability to verbally identify the object indicates that the left hemisphere, which is responsible for language processing, does not have access to the information presented in the left visual field.
24.
Which of the following is FALSE about brain plasticity?
Correct Answer
B. After childhood, the functional organization of the human brain is unchangeable
Explanation
The statement that "After childhood, the functional organization of the human brain is unchangeable" is FALSE. Brain plasticity refers to the brain's ability to change and adapt throughout life. Even after childhood, the brain can still reorganize its neural connections and modify its functional organization in response to learning, experiences, and environmental influences. This phenomenon is known as neuroplasticity and has been observed in various studies. Therefore, the functional organization of the human brain is not fixed and can be modified throughout adulthood.
25.
Which of the following is TRUE about hemispheric specialization?
Correct Answer
B. The left hemispHere is generally specialized for language function, while the right hemispHere seems to be better at appreciating spatial relationships among objects
Explanation
The left hemisphere is generally specialized for language function, while the right hemisphere seems to be better at appreciating spatial relationships among objects. This is supported by research on hemispheric specialization, which has shown that language processing, such as speech production and comprehension, is primarily localized in the left hemisphere. On the other hand, the right hemisphere is involved in processing visual-spatial information and is better at tasks like recognizing faces and understanding spatial relationships between objects. This division of functions between the two hemispheres is known as hemispheric specialization or lateralization.
26.
Broca's and Wernicke's aphasia can be distinguished because Broca's aphasia involves the ___________ area of the brain and results in difficulty with speech ____________, while Wernicke's aphasia involves the ____________ area of the brain and results in difficulty with speech ____________.
Correct Answer
C. Frontal, production; temporal/parietal, comprehension
Explanation
Broca's aphasia involves the frontal area of the brain and results in difficulty with speech production. This means that individuals with Broca's aphasia have trouble forming words and sentences. On the other hand, Wernicke's aphasia involves the temporal/parietal area of the brain and results in difficulty with speech comprehension. This means that individuals with Wernicke's aphasia have difficulty understanding spoken and written language.
27.
Due to a minor stroke, Kerry has a tiny lesion in the left primary visual cortex. The most likely result will be:
Correct Answer
D. A small "hole" in a particular region of the right visual field
Explanation
The left primary visual cortex is responsible for processing visual information from the right visual field. Therefore, a lesion in this area would result in a small "hole" in a particular region of the right visual field.
28.
The central nervous system (CNS) consists of the ____________ and the ____________.
Correct Answer
B. Brain; spinal cord
Explanation
The central nervous system (CNS) is made up of the brain and the spinal cord. These two components work together to process and coordinate information throughout the body. The brain is responsible for higher-level functions such as thinking, memory, and emotions, while the spinal cord acts as a pathway for transmitting signals between the brain and the rest of the body. Together, they form the central command center of the nervous system, controlling and regulating various bodily functions.
29.
Neurons are made up of:
Correct Answer
D. Cell body, axon, and dendrites
Explanation
Neurons are the basic building blocks of the nervous system and are composed of three main parts: the cell body, axon, and dendrites. The cell body contains the nucleus and other organelles necessary for the neuron's functioning. The axon is a long, slender projection that carries electrical signals away from the cell body to other neurons or muscles. Dendrites are shorter, branch-like projections that receive incoming signals from other neurons. Together, these three components allow neurons to transmit and process information throughout the body.
30.
Suppose a single postsynaptic neuron receives input from many fast synapses. What will determine its response to this input?
Correct Answer
B. It will integrate the incoming excitatory and inhibitory signals, with its rate of action potentials depending on the relative amount of each type of signal
Explanation
The correct answer is that the postsynaptic neuron will integrate the incoming excitatory and inhibitory signals, with its rate of action potentials depending on the relative amount of each type of signal. This means that the neuron will combine and process the incoming signals from different synapses, taking into account both the excitatory and inhibitory inputs. The rate at which the neuron fires action potentials will be determined by the balance between these two types of signals. If there are more excitatory signals, the neuron is more likely to produce action potentials, while an increase in inhibitory signals will decrease the rate of action potentials.
31.
Grace was out on a crowded dance floor when the person dancing next to her accidentally kicked her in the leg. Which type of neuron carried the pain information from her leg to the central nervous system?
Correct Answer
D. Sensory Neurons
Explanation
Sensory neurons are responsible for carrying pain information from the leg to the central nervous system. These neurons are specialized to detect and transmit sensory information, including pain, from various parts of the body to the brain. In this case, when Grace was kicked in the leg, the sensory neurons in her leg would have detected the pain stimulus and transmitted the information to the central nervous system, allowing her to perceive the pain sensation.
32.
The spinal reflex arc is:
Correct Answer
C. Controlled entirely at the level of the spinal cord
Explanation
The correct answer is "controlled entirely at the level of the spinal cord." The spinal reflex arc refers to the pathway that allows for a quick and automatic response to a stimulus without the involvement of the brain. This reflex arc is mediated by neurons in the spinal cord, which receive sensory input and send motor output to produce a reflexive response. The absence of brain involvement allows for a rapid response, such as quickly withdrawing a hand from a hot surface, without the need for conscious thought or decision-making.
33.
Which of the following is NOT true about sleep?
Correct Answer
C. REM sleep happens once per night
Explanation
During REM sleep, our skeletal muscles are almost completely inactive. This is because REM sleep is characterized by rapid eye movements and vivid dreaming, while our skeletal muscles experience temporary paralysis, known as REM atonia. This prevents us from physically acting out our dreams and potentially harming ourselves or others. Therefore, the statement "REM sleep happens once per night" is not true, as we cycle through multiple REM and non-REM sleep stages throughout the night.
34.
As you fall asleep, how do your EEG wave patterns change as you go from being alert, to being relaxed, to being deep asleep?
Correct Answer
A. Beta waves --> alpHa waves --> delta waves
Explanation
As you fall asleep, your EEG wave patterns change from beta waves to alpha waves to delta waves. Beta waves are associated with alertness and active thinking. As you start to relax, alpha waves become dominant, indicating a state of relaxation and calmness. Finally, as you transition into deep sleep, delta waves become prominent, reflecting the slowest and highest amplitude brain waves. These delta waves are characteristic of deep, restorative sleep.
35.
According to the feature-integration theory of attention, which of the following is NOT true?
Correct Answer
D. Whereas binding of complex stimulus features requires attention, binding of simple stimulus features (such as colour, shape, or orientation) does not
Explanation
According to the feature-integration theory of attention, it is NOT true that binding of simple stimulus features (such as color, shape, or orientation) does not require attention. The theory suggests that attention is required to bind different features together in an object, regardless of whether the features are simple or complex. Therefore, the statement contradicts the theory by implying that simple stimulus features can be bound without attention.
36.
As sleep cycles progress over the course of an average night, the amount of time spent in REM sleep:
Correct Answer
B. Increases
Explanation
As sleep cycles progress over the course of an average night, the amount of time spent in REM sleep increases. This is because REM sleep, also known as rapid eye movement sleep, is a stage of sleep characterized by vivid dreaming and heightened brain activity. REM sleep typically occurs in shorter intervals at the beginning of the night and becomes longer and more frequent as the night progresses. Therefore, the correct answer is that the amount of time spent in REM sleep increases over the course of the night.
37.
Distinguishing a severely brain damaged individual as being in a vegetative state, compared to a minimally conscious state, or locked-in state, is:
Correct Answer
B. Difficult since contingencies between stimuli and behaviour can be difficult to observe in all three
Explanation
The answer is difficult since contingencies between stimuli and behavior can be difficult to observe in all three states. This means that it is challenging to determine the specific state a severely brain damaged individual is in because the relationship between the stimuli they receive and their resulting behavior is not easily observable. This difficulty applies to distinguishing between a vegetative state, a minimally conscious state, and a locked-in state.
38.
Which of the following is TRUE about visual search tasks?
Correct Answer
D. Search is serial for conjunctions of features, but parallel for single features
Explanation
In visual search tasks, the correct answer states that search is serial for conjunctions of features, but parallel for single features. This means that when searching for an object that has multiple features combined (conjunctions of features), such as a red triangle, the search process is done in a sequential manner. However, when searching for an object that has only one distinct feature, such as a red or a triangle, the search process can be done simultaneously for all the objects in the visual field.
39.
The Gestalt law of similarity predicts that:
Correct Answer
B. Similar elements are perceptually grouped together
Explanation
The Gestalt law of similarity states that similar elements are perceptually grouped together. This means that when presented with a group of objects or elements, our brain tends to perceive those that are similar in terms of shape, color, size, or other attributes as belonging to the same group or category. This grouping helps us organize and make sense of the visual information we receive, allowing us to perceive patterns and relationships between objects.
40.
A white shirt is seen as being equally bright outside on a sunny day and in a dimly lit room. This is because:
Correct Answer
D. Lightness constancy compensates for a different in the amount of light reflected
Explanation
Lightness constancy is the ability of our visual system to perceive the relative lightness of an object regardless of the lighting conditions. In this case, the white shirt appears equally bright in both the sunny day and dimly lit room because lightness constancy compensates for the difference in the amount of light reflected. Our brain adjusts the perception of brightness to account for the varying lighting conditions, allowing us to perceive the shirt as equally bright in both environments. This phenomenon demonstrates how our visual system can maintain a consistent perception of an object's brightness despite changes in lighting.
41.
Generally speaking, the value of sensory adaptation is that it:
Correct Answer
C. Allows us to vary our attention between the changing and stable aspects of our environment
Explanation
Sensory adaptation enables us to filter out constant or unchanging stimuli, freeing up attention for new or changing stimuli. This flexibility helps us adapt to our surroundings effectively by focusing on what is relevant while ignoring what remains constant.
42.
Weber fractions relate the ____________ to the ______________.
Correct Answer
C. JND; magnitude of the stimulus
Explanation
Weber fractions relate the Just Noticeable Difference (JND) to the magnitude of the stimulus. The JND refers to the smallest change in a stimulus that can be detected by a person. The Weber fraction is a constant ratio that determines the relationship between the JND and the magnitude of the stimulus. It helps explain how sensitive we are to changes in stimuli and how our perception is influenced by the magnitude of the stimulus.
43.
Suppose that you have just finished working out and decide to take a shower. You are also expecting an important phone call, and so decide that you will listen extra carefully for the ringing of the phone. Two or three times, you pop your head out of the shower thinking that you hear the phone, but it didn't really ring. Your experience of listening to the phone has to do with:
Correct Answer
B. Your response bias
Explanation
The correct answer is "your response bias". In this scenario, the person's expectation of an important phone call causes them to be more alert and attentive to any potential ringing sound. As a result, they may perceive non-existent ringing sounds and pop their head out of the shower. This is an example of a response bias, where their expectation influences their perception and response to a stimulus. The other options, such as just noticeable differences, absolute threshold, and Weber's fraction, do not accurately explain the person's experience in this situation.
44.
Visual acuity is sharpest when images cast by environmental stimuli fall directly on the fovea because:
Correct Answer
A. Each cone synapses directly onto a single ganglion cell and there is a concentration of cones in the fovea
Explanation
The fovea is the central area of the retina where visual acuity is the sharpest. This is because each cone in the fovea directly connects to a single ganglion cell, allowing for a more precise transmission of visual information. Additionally, the fovea contains a high concentration of cones, which are responsible for color vision and detailed visual perception. This concentration of cones in the fovea further enhances visual acuity in this area.
45.
Which of the following does NOT contribute to our depth perception?
Correct Answer
A. The density of cones at the fovea
Explanation
The density of cones at the fovea refers to the concentration of cone cells in the central part of the retina, which is responsible for detailed vision. This high density of cones contributes to our depth perception by providing clear and precise visual information. Therefore, the density of cones at the fovea does contribute to our depth perception, making it the correct answer for what does NOT contribute to it.
46.
Visual information is sent via the optic nerve to the ___________, which, in turn, sends it to the _________.
Correct Answer
C. Thalamus; primary visual cortex
Explanation
The visual information is first sent via the optic nerve to the thalamus. The thalamus acts as a relay station and processes the information before sending it to the primary visual cortex, which is located in the occipital lobe. The primary visual cortex is responsible for further processing and interpreting the visual information.
47.
Which of the following is TRUE about vision?
Correct Answer
D. Colour vision is the result of the relative firing of the cone receptors
Explanation
Colour vision is the result of the relative firing of the cone receptors. This means that different cone receptors in the retina are sensitive to different wavelengths of light, allowing us to perceive different colors. The brain then interprets the relative activation of these cone receptors to perceive and differentiate between different colors. This is why we can see a wide range of colors in our visual environment.
48.
Information from the right visual field is conveyed:
Correct Answer
C. To the left visual cortex in the occipital lobe
Explanation
Information from the right visual field is conveyed to the left visual cortex in the occipital lobe because the visual pathways in the brain cross over at the optic chiasm. This means that the right visual field is processed by the left side of the brain. The occipital lobe is responsible for processing visual information, so the correct answer is that information from the right visual field is conveyed to the left visual cortex in the occipital lobe.
49.
For light waves, amplitude is to ___________ as wavelength is to _____________.
Correct Answer
B. Brightness; colour
Explanation
Amplitude is a measure of the intensity or brightness of a light wave, while wavelength determines the color of the light. The greater the amplitude, the brighter the light appears, and the shorter the wavelength, the bluer the light appears. Therefore, the correct answer is "brightness; colour."
50.
How can humans recognize over 10,000 different odours when we have only a few hundred types of receptors?
Correct Answer
A. Different odorants attach to different combinations of receptors
Explanation
Different odorants attach to different combinations of receptors, allowing humans to recognize over 10,000 different odors. Each odorant molecule can bind to multiple receptors, and the specific combination of receptors that are activated by a particular odorant creates a unique pattern of neural activity. This pattern is then processed by the brain, enabling us to distinguish between different smells. Therefore, even though humans have only a few hundred types of receptors, the ability to detect a wide range of odors is achieved through the diverse combinations of receptors that can be activated by different odorants.