You Think You Know About Human Biology? Pass This Biology Quiz

When a person's eyes are subjected to a bright light and then they are carried to a dark room, the pupil of the eye undergoes a process called dilation, where it expands to allow more light to enter the eye. This causes the distance (X) between the lens and the retina to increase. At the same time, the amount of light entering the eye decreases in the dark room, causing the distance (Y) between the lens and the near point of distinct vision to decrease. Therefore, (X) increases while (Y) decreases.

When you feel a sharp pinch in your arm, it is most likely because the needle of the injection has penetrated your skin. Pain receptors in the skin are responsible for detecting and transmitting the sensation of pain to the brain. These receptors are specifically designed to respond to potentially damaging stimuli, such as the needle of an injection, and send signals to the brain to alert you of the pain. Therefore, it is the pain receptors in the skin that would most likely detect the stimulus of a sharp pinch during an injection.

Reflex actions do not require thinking because signals are not passed to the brain, allowing the body to respond more quickly. This is beneficial because it allows for immediate and automatic responses to potential threats or dangers, without the delay of conscious thought. By bypassing the brain and sending signals directly to the spinal cord, reflex actions can be executed rapidly, helping to protect the body from harm.

The independent variable in this investigation is the time of day. This is because the investigator is planning to measure reflex-reaction times and wants to determine if the time of day has any effect on these times. The other options listed (ruler, person, distance the ruler is dropped from, and distance the ruler is caught at) are not independent variables in this context as they are not being manipulated or changed by the investigator.

Motor neuron disease is characterized by the progressive breakdown and damage of motor neurons in the nervous system. This leads to difficulties in motor function, including moving around and holding objects. Loss of smell and taste, increased tolerance to pain and heat, increased speed of reflexes, and a persistent cough and sore throat are not typically associated with motor neuron disease.

The olfactory lobe consists of the anterior olfactory bulb and the posterior olfactory tract. These two options are the correct components of the olfactory lobe. The anterior olfactory bulb is responsible for receiving sensory information from the olfactory receptors in the nose, while the posterior olfactory tract carries this information to other areas of the brain for further processing. Therefore, the correct answer is "The two previous options."

The figure in the question is a simplified diagram of the human brain, specifically showing a lateral view. It highlights the cerebral cortex and the hindbrain, with a particular focus on the parietal lobe. The parietal lobe is responsible for processing sensory information and plays a role in spatial awareness and perception. Therefore, the correct answer is the one that accurately describes the figure as showing the cerebral cortex, hindbrain, and highlighting part of the parietal lobe.

The frontal lobe is responsible for controlling voluntary movements, such as walking and talking. It also plays an important role in memory and speech. This lobe is involved in decision-making, problem-solving, and social behavior. It is located at the front of the brain, just behind the forehead.

The peripheral nerves that feed the urinary bladder arise from the lumbar and sacral regions of the spinal cord. These regions are responsible for controlling the bladder and its function. The nerves from these regions send signals to the bladder, allowing it to contract and release urine. The thoracic region is not involved in bladder control, and the brain stem is not directly connected to the bladder. Therefore, the correct answer is the lumbar and sacral regions.

The brain does not have pain receptors. This is because the brain itself does not feel pain. While the brain is responsible for processing and interpreting pain signals from other parts of the body, it does not have pain receptors of its own. Therefore, it is not able to perceive pain directly.

Sympathetic innervation of the liver regulates the function of formation of glucose from glycogen. This process, known as glycogenolysis, occurs when the body needs to increase blood glucose levels, such as during periods of stress or low blood sugar. The sympathetic nervous system stimulates the liver to break down glycogen into glucose, which can then be released into the bloodstream to provide energy to the body.

The frontal lobe is responsible for controlling higher mental activities like reasoning. It is involved in decision making, problem-solving, planning, and cognitive functions such as attention, memory, and language. This part of the brain plays a critical role in executive functions and is involved in regulating emotions and social behavior.

The peripheral nervous system consists of nerves that form the communication network between the central nervous system and the body parts. The central nervous system, which includes the brain and spinal cord, is responsible for processing and coordinating information received from the peripheral nervous system. It controls and regulates bodily functions and movements. Therefore, the central nervous system is the correct answer as it is directly involved in the communication network between the body parts and the peripheral nervous system.

The medulla oblongata is responsible for controlling vital functions such as heartbeat, breathing, and blood pressure. It is located at the base of the brainstem and serves as a relay station between the brain and the spinal cord. The medulla oblongata contains various centers that regulate these essential physiological processes, making it the correct answer.

The thalamus serves as a "gate" for filtering information from various channels, except smell, before it is received and processed. It acts as a relay station, receiving sensory information from the body and sending it to the appropriate areas of the brain for further processing.

Cranial nerve (III) is the oculomotor nerve, which controls the movement of the eye. Unlike the other cranial nerves listed, it is not primarily sensory in function. The olfactory nerve is responsible for the sense of smell, the optic nerve is responsible for vision, and cranial nerve (VII) is responsible for taste. Therefore, cranial nerve (III) is the correct answer because it is the only one that is not primarily sensory.

The sympathetic nerve that stimulates the secretion of epinephrine hormone in the blood arises from the lumbar region of the spinal cord.

Cerebrospinal fluid is found in the layer of the meninges called the arachnoid mater. The arachnoid mater is the middle layer of the meninges and is located between the dura mater (outer layer) and the pia mater (inner layer). It forms a protective barrier around the brain and spinal cord and contains cerebrospinal fluid, which acts as a cushion to protect against trauma and provides nutrients to the nervous system tissue.

The spinal cord is the main center of reflex actions in the body. It is responsible for coordinating and transmitting signals between the brain and the rest of the body. Reflex actions are quick, involuntary responses to stimuli, and the spinal cord plays a crucial role in initiating and coordinating these responses. The other options, such as the cerebellum, medulla oblongata, and midbrain, are also important parts of the central nervous system, but they do not serve as the main center for reflex actions.

The correct answer is "Reflex arc" because the question asks for the main components of something, and out of the given options, only the reflex arc is a component. The other options, such as the central nervous system, peripheral nervous system, and transmission of nerve impulse, are not components but rather related concepts or processes within the nervous system.

Neurons communicate with one another both electrically and chemically. Electrical communication occurs through the transmission of electrical impulses along the axon of a neuron. These impulses can travel quickly and allow for rapid communication. Chemical communication occurs at the synapse, where neurotransmitters are released from one neuron and bind to receptors on another neuron, transmitting the signal. This chemical communication is slower but allows for more complex and specific signaling. Therefore, the correct answer is D, as both electrical and chemical communication are involved in neuron communication.

The letter "C" shows the site that controls the heart rate and breathing rate. This suggests that there is a specific location or organ represented by the letter "C" that is responsible for regulating these essential bodily functions.

The sympathetic system is responsible for the "fight or flight" response in the body, which can increase blood pressure. On the other hand, the parasympathetic system is responsible for the "rest and digest" response, which can lower blood pressure. Therefore, by deactivating the action of the sympathetic system and activating the parasympathetic system, the doctor can help lower the patient's high blood pressure.

The dendrites of a sensory neuron are found in the sensory organ. The sensory organ is responsible for detecting stimuli from the environment and transmitting this information to the central nervous system. In a reflex arc, the sensory neuron receives sensory input from the sensory organ and sends signals to the central nervous system, which then coordinates a reflex response. The dendrites of the sensory neuron receive the sensory input and transmit it to the cell body for further processing and transmission. Therefore, the correct answer is sensory organ.

In this reflex action, the effector is the muscles in your leg. When someone shouts "fire!" and you start running without thinking, the muscles in your leg are responsible for the action of running. They receive signals from the brain and contract to produce the movement necessary for running.

The brain consists of three parts.

The cerebral hemispheres are divided into four lobes by sulci. Sulci are the grooves or furrows on the surface of the brain that separate the different lobes. Gyri, on the other hand, are the raised folds or ridges between the sulci. Therefore, the correct answer is sulci.

The somatic nervous system controls voluntary movements and sensory information from the external environment. Activity 2 refers to voluntary movements, which are under the control of the somatic nervous system. Activity 5 refers to the sense of touch, which is also controlled by the somatic nervous system. Therefore, the correct answer is 2 and 5.

When there is an influx of calcium ions into the synaptic knob, it triggers the fusion of vesicles containing acetylcholine with the presynaptic membrane. This allows the release of acetylcholine into the synapse, where it can bind to receptors on the postsynaptic membrane and initiate a response in the next neuron.

The center of feeling pain is not a component of a reflex arc. A reflex arc is a neural pathway that controls reflex actions, which are rapid and involuntary responses to stimuli. The components of a reflex arc include sensory neurons that detect the stimulus, interneurons that transmit the signal to the appropriate motor neurons, and motor neurons that carry the signal to the effector (muscle or gland) to produce a response. The center of feeling pain is not directly involved in the reflex arc pathway.

Activation of the sympathetic nervous system typically leads to an increase in heart rate, as it prepares the body for a "fight or flight" response. However, a decrease in heart rate is not caused by sympathetic activation. Instead, a decrease in heart rate is typically associated with the activation of the parasympathetic nervous system, which promotes relaxation and rest.

White matter consists of myelinated axons. Myelinated axons are nerve fibers that are covered in a fatty substance called myelin, which gives them a white appearance. These axons are responsible for transmitting electrical signals between different areas of the brain and spinal cord, allowing for communication and coordination of various functions in the body. The presence of myelin helps to speed up the transmission of these signals, making white matter an essential component of the central nervous system.

The Dura mater is a tough, fibrous membrane that covers and protects the brain and spinal cord. It acts as a protective barrier, shielding these vital organs from injury and external forces. It also helps to maintain the shape and structure of the brain and spinal cord, preventing them from being compressed or distorted.

The grey matter of the brain is due to the presence of nerve cells. Nerve cells, also known as neurons, are the basic building blocks of the nervous system. They are responsible for transmitting and processing information through electrical and chemical signals. The grey matter of the brain contains a high concentration of nerve cells, which give it its characteristic grey appearance. Axons, dendrites, and Nissl granules are all components of nerve cells, but they alone do not contribute to the grey matter.

The left frontal lobe is responsible for controlling the movement of the right side of the body. This is because the brain is cross-wired, meaning that the left hemisphere of the brain controls the right side of the body and vice versa. Therefore, damage or impairment to the left frontal lobe can result in difficulties or loss of movement on the right side of the body.

The correct answer is 4 : 1. This means that the weight of the brain in adults is approximately four times that of newborn babies. As individuals grow and develop, their brains also grow in size and weight. This ratio suggests that the brain undergoes significant growth and development during the early stages of life.

The correct answer is (1) is incorrect / (2) is correct. This is because statement (1) is incorrect as not all peripheral nerves are autonomic. The peripheral nervous system consists of both the autonomic and somatic nervous systems. The autonomic nervous system, mentioned in statement (2), is indeed a part of the peripheral nervous system.

The sensory system is responsible for receiving and processing sensory information from the environment. It plays a crucial role in the initiation of reflex movements, as it detects stimuli and triggers automatic responses without conscious control. The sensory system is also involved in learning processes, as it allows individuals to acquire new information and adapt their behavior accordingly. Additionally, the sensory system contributes to the initiation of emotional responses by processing sensory input that elicits emotional reactions. However, the initiation of voluntary movements is primarily controlled by the motor system, which is responsible for executing intentional actions based on conscious decisions rather than sensory input.

The autonomic nervous system is divided into two main components: the sympathetic nervous system and the parasympathetic nervous system. The sympathetic nervous system prepares the body for "fight or flight" responses, while the parasympathetic nervous system promotes "rest and digest" activities. These two components work together to regulate involuntary bodily functions such as heart rate, digestion, and breathing.

The correct answer is A. The part of the brain that controls balance is the cerebellum. It is responsible for coordinating voluntary movements, maintaining balance, and posture.

When watching a scary movie, the body's natural fight or flight response is triggered. This response causes the body to release stress hormones, such as adrenaline, which can lead to various physical reactions. One of these reactions is a decrease in saliva production, resulting in a dry mouth. This is because the body is preparing for potential danger and diverting its resources away from non-essential functions, such as saliva production, towards more vital functions like increased heart rate and heightened senses.

The parietal lobe is responsible for processing sensory information, including touch and proprioception (awareness of body position and movement). In this case, the man's loss of sensation in his right leg suggests damage to the parietal lobe, as this is the region responsible for interpreting sensory input from the leg. However, the fact that he can still move his leg indicates that the motor cortex, which controls voluntary movement, is not affected.

Receptors in the human body are responsible for detecting changes in the external environment. These changes can be in the form of temperature, pressure, light, or chemical signals. Once the receptors detect these changes, they transmit signals to the central nervous system, which then processes and interprets the information. This allows the body to respond appropriately to the external stimuli and maintain homeostasis.

The forebrain is the largest and most complex part of the brain. It is responsible for many higher-order functions such as thinking, memory, and sensory processing. The forebrain is divided into two main parts: the cerebral cortex and the subcortical structures. The cerebral cortex is responsible for conscious thought and voluntary actions, while the subcortical structures are involved in regulating emotions, controlling movement, and processing sensory information. Therefore, it can be concluded that the forebrain forms approximately two-thirds of the brain.

The limbic system, also known as the emotional brain, consists of the hippocampus and amygdala. These two structures play crucial roles in processing emotions and memory. The hippocampus is involved in the formation and retrieval of long-term memories, while the amygdala is responsible for processing emotions, particularly fear and aggression. Together, they contribute to emotional regulation and memory consolidation. The other options, thalamus and hypothalamus, are not part of the limbic system.

None of the above statements are correct because they do not accurately describe the layers of meninges protecting the brain and spinal cord. The correct statement is that the brain is surrounded by dura mater, arachnoid, and pia mater, while the spinal cord is also protected by dura mater, arachnoid, and pia mater.

The adrenal gland does not receive nerve supply from the brain stem. The brain stem is responsible for regulating many vital functions in the body, including controlling the autonomic nervous system. However, the adrenal gland receives its nerve supply from the sympathetic nervous system, which is not directly controlled by the brain stem. Instead, the sympathetic nerves that innervate the adrenal gland originate from the thoracic and lumbar regions of the spinal cord. This allows the adrenal gland to function independently from direct control by the brain stem.

In a situation where a person sees a car speeding towards him, the autonomic nervous system would trigger various responses to prepare the body for a fight-or-flight response. These responses include vasodilating blood vessels to supply more oxygen to the skeletal muscles, increasing heart rate to pump more blood to the muscles, dilating bronchioles to increase oxygen intake, and relaxing the urinary bladder to allow for better focus on survival. However, contracting the stomach wall would not be a response triggered by the autonomic nervous system in this situation as digestion and absorption of nutrients are not a priority during a potentially life-threatening event.

The correct answer is (i) and (iv). This means that both statement (i) and statement (iv) are true.

The peripheral nervous system of a human consists of nerves that extend from the brain and spinal cord to the rest of the body. The spinal nerves are a part of this system and are responsible for transmitting sensory and motor information between the spinal cord and the rest of the body. There are a total of 31 pairs of spinal nerves in the peripheral nervous system, with each pair connecting to a specific region of the body.

The parasympathetic system influences the various organ systems of the body through connections emerging from the brain and sacral regions of the spinal cord. These nerves help regulate functions such as digestion, heart rate, and relaxation. The brain and sacral regions are important in coordinating the parasympathetic response throughout the body.

If part C in the four brains is damaged, it would lead to a difficulty with vision and hearing.

The correct answer is B. In the table, it is stated that the sympathetic nervous system increases heart rate, while the parasympathetic nervous system decreases heart rate. This is a correct description of the effects of these two systems on the heart rate.

The vision sight depends upon the complementarity between the action of the occipital lobe together with the midbrain and the autonomic nervous system. The occipital lobe is responsible for processing visual information, while the midbrain plays a role in visual attention and eye movement control. The autonomic nervous system regulates involuntary bodily functions, including the dilation and constriction of the pupils in response to light. Therefore, the interaction between the midbrain and the autonomic nervous system is essential for coordinating visual perception and response.

The frontal lobe does not play a role in controlling any of the human five basic senses. The parietal lobe is responsible for processing sensory information such as touch and temperature. The occipital lobe is responsible for processing visual information. The temporal lobe is involved in processing auditory information and is also responsible for language comprehension. However, the frontal lobe is primarily responsible for higher cognitive functions such as decision-making, problem-solving, and personality.

The dependent variable in this investigation is the distance the ruler is caught at (in centimeters). This means that the distance the ruler travels after being dropped is being measured and observed as the outcome or result of the reflex-reaction times being tested.

Activation of the sympathetic nervous system triggers the "fight or flight" response, which is a physiological reaction to stress or danger. This response involves various changes in the body to prepare for action. Vasodilatation in skeletal muscle increases blood flow to the muscles, sweating helps regulate body temperature, and bladder relaxation allows for the emptying of urine. However, increased gut motility is not part of the "fight or flight" response. Instead, the sympathetic nervous system inhibits gut motility to redirect energy and resources to other parts of the body.

The man's ability to feel objects touching his hand suggests that the receptors in his hand are still functioning. However, his inability to move his hand away from the objects indicates a problem with the nerve connection between his central nervous system and the muscles of his arm. This suggests that the injury has affected the motor nerves that control the movement of his hand muscles, while leaving the sensory nerves intact.

The autonomic nervous system is responsible for regulating involuntary bodily functions, such as blood pressure and respiration. It controls the dilation and constriction of blood vessels, which affects blood pressure, and it regulates the rate and depth of breathing. The autonomic nervous system does not directly affect the parts of the brain involved in memory or the ear's ability to hear faint whispers and loud cries. Therefore, the correct answer is blood pressure and respiration.

The medulla oblongata is a part of the brainstem that controls many vital functions, including regulating the activity of the autonomic nervous system. It plays a crucial role in controlling involuntary actions such as heart rate, blood pressure, breathing, and digestion. The medulla oblongata receives information from various parts of the body and sends out signals to different organs to maintain homeostasis. Therefore, it is the brain area that most directly regulates the activity of the autonomic nervous system.

In this reflex action, the effector refers to the part of the body that carries out the response or action. When you accidentally touch a hot baking tray, the muscles in your arm contract and pull your arm away from the heat. Therefore, the correct answer is the muscles in your arm, as they are responsible for the movement of your arm in response to the hot baking tray.

Nerve fibres from the brain stem control various functions in the body. Increasing salivary secretion, increasing gastric secretion, and decreasing glucose level in the blood are all functions that can be controlled by nerve fibres from the brain stem. However, increasing heartbeats is not directly controlled by nerve fibres from the brain stem. The heart has its own intrinsic electrical system that regulates its beating, known as the cardiac conduction system. While the brain can influence heart rate through the autonomic nervous system, the direct control of heartbeats is not a function controlled by nerve fibres from the brain stem.

The pons, cerebellum, and medulla are all parts of the hindbrain. The hindbrain is located at the back of the brain and is responsible for controlling basic bodily functions such as breathing, heart rate, and balance. The pons helps to relay messages between different parts of the brain, the cerebellum coordinates movement and balance, and the medulla controls vital functions such as breathing and blood pressure. Therefore, the correct answer is hindbrain.

The correct answer is "The cell bodies of sensory neurons that bring information from the periphery to the spinal cord." This is because dorsal root ganglia are clusters of cell bodies located along the dorsal roots of the spinal nerves. These cell bodies belong to sensory neurons, which transmit information from sensory receptors in the periphery (such as the skin, muscles, and organs) to the spinal cord. Therefore, the statement accurately describes the contents of the dorsal root ganglia.

The grey matter of the spinal cord contains dendrites of connector and motor neurons. Connector neurons, also known as interneurons, are responsible for connecting sensory and motor neurons within the spinal cord. Motor neurons, on the other hand, transmit signals from the central nervous system to muscles and glands, allowing for voluntary movement. Therefore, the grey matter of the spinal cord contains dendrites of both connector and motor neurons.

The brain stem is composed of the medulla oblongata, pons varolii, and midbrain. The medulla oblongata is responsible for controlling vital functions such as breathing, heart rate, and blood pressure. The pons varolii acts as a bridge connecting different parts of the brain and is involved in functions such as sleep and arousal. The midbrain plays a role in sensory processing, motor control, and the regulation of sleep-wake cycles.

Reflex actions are involuntary and rapid responses to stimuli that bypass conscious control. These actions are controlled by a part of the central nervous system, specifically the spinal cord and lower brainstem. The autonomic nervous system controls involuntary bodily functions like heart rate and digestion, while the peripheral nervous system consists of the nerves that connect the central nervous system to the rest of the body. Therefore, neither the autonomic nor peripheral nervous system control reflex actions.