Chapter 2 Physiological Psychology Mid-term Study Quiz

Diffusion is the process by which particles move from an area of higher concentration to an area of lower concentration. In the case of sugar left at the bottom of a glass of water, the sugar particles will naturally move and spread out throughout the water due to diffusion. This is because the concentration of sugar is higher at the bottom initially, and over time, the sugar particles will randomly move and mix with the water particles, resulting in an even distribution of sugar throughout the glass.

Sensory neurons gather information from the environment and transmit it to the interneurons. Interneurons then process and relay this information to the motor neurons. Finally, motor neurons receive the message from the brain and send signals to the muscles, causing them to contract.

The mitochondria is responsible for producing ATP, which stands for adenosine triphosphate. ATP is considered the energy currency of the cell and is used as a source of energy for various cellular processes and functions. Therefore, the correct answer is "energy for functioning in the cell."

The mitochondria is often referred to as the "power plant" of the cell because it is responsible for producing the majority of the cell's energy in the form of adenosine triphosphate (ATP) through a process called cellular respiration. This energy is essential for the cell to carry out its various functions and processes. Therefore, the term "power plant" accurately describes the role of mitochondria in providing energy to the cell.

Synaptic vesicles are responsible for holding neurotransmitters in little bubbles, ready to be released at the terminal buttons when an action potential signals it. These vesicles store and transport the neurotransmitters, allowing them to be released into the synapse and transmit signals from one neuron to another.

The correct answer is "selectively permeable; lipid molecules". The cell membrane is selectively permeable, which means it allows certain molecules to pass through while preventing others from crossing. It is composed of a double layer of lipid molecules, specifically phospholipids, which have hydrophilic heads and hydrophobic tails. This lipid bilayer structure gives the cell membrane its selective permeability and allows it to regulate the movement of substances in and out of the cell.

Ribosomes are responsible for protein synthesis in cells. They are located on the granular endoplasmic reticulum, which is involved in the production, folding, and transport of proteins. Therefore, the term "protein factories" accurately describes the role of ribosomes in the cell.

Hormones are chemical messengers that are produced by glands and released into the bloodstream. They travel through the bloodstream to reach their target organs or cells, where they exert their effects. Therefore, the correct answer is "bloodstream" as it is the main pathway through which hormones are transported throughout the body.

Terminal buttons are responsible for secreting neurotransmitters. Terminal buttons, also known as synaptic knobs, are located at the ends of axons and are responsible for transmitting signals to other neurons. When an action potential reaches the terminal buttons, they release neurotransmitters into the synapse, which then bind to receptors on the postsynaptic neuron and transmit the signal. This process allows for communication between neurons and is essential for the functioning of the nervous system.

Neuroglia refers to a type of cells found in the nervous system that provide support and protection to neurons. Astrocytes, oligodendrocytes, and Schwann cells are all examples of neuroglia. Astrocytes regulate the chemical environment around neurons, oligodendrocytes produce myelin to insulate axons in the central nervous system, and Schwann cells perform the same function in the peripheral nervous system. Therefore, neuroglia is the correct answer as it encompasses all these types of cells that play crucial roles in supporting and protecting neurons.

Sodium is positively charged, just like the outside of the cell. Due to this positive charge, sodium wants to move inside the cell. However, the cell membrane is only partially permeable to sodium, meaning it allows only some sodium ions to pass through. Additionally, there is a special pump in the cell membrane that actively pushes sodium ions back out of the cell, maintaining a balance and preventing an excessive buildup of sodium inside the cell.

If the applied electricity is not enough to reach the threshold of excitation, the cell would not undergo any changes. This means that neither the potassium ion channel nor the sodium ion channel would open. Without the opening of these ion channels, there would be no movement of ions across the cell membrane, and therefore, no action potential or any other cellular response would occur.

Astrocytes are a type of glial cell in the central nervous system that play a crucial role in providing nutrition and physical support to surrounding cells. They help maintain the homeostasis of the extracellular environment by regulating the levels of ions, neurotransmitters, and metabolites. They also form a structural framework for neurons, providing them with physical support. Additionally, astrocytes are involved in the formation and maintenance of the blood-brain barrier, which further supports their role in providing nutrition and support to surrounding cells.

Cell organelles are subcellular structures that perform various functions in a cell. They are specialized compartments within a cell that carry out specific tasks such as energy production, protein synthesis, and waste disposal. Examples of cell organelles include the nucleus, mitochondria, endoplasmic reticulum, and Golgi apparatus. These organelles work together to maintain the overall function and integrity of the cell.

The granular endoplasmic reticulum, also known as rough endoplasmic reticulum, is responsible for producing and packaging proteins. This organelle contains ribosomes on its surface, which are responsible for protein synthesis. As proteins are synthesized, they are transported into the rough endoplasmic reticulum where they undergo further processing and packaging before being transported to their final destination within the cell or outside of it. Therefore, the correct answer is proteins.

Oligodendrocytes are a type of glial cell in the central nervous system that play a crucial role in the process of myelination. Myelination involves the formation of a protective sheath called myelin around the axons of neurons, which helps to increase the speed and efficiency of electrical signal transmission. Oligodendrocytes are responsible for myelinating multiple segments of several neurons, making them essential for proper neural communication and function.

During an action potential, the rapid depolarization of the cell membrane is a result of sodium ion channel gates opening. This allows an influx of sodium ions into the cell, leading to a change in the membrane potential and the initiation of the action potential.

The golgi apparatus is often referred to as the "packaging center" of the cell world because it is responsible for modifying, sorting, and packaging proteins and lipids into vesicles for transport to their final destinations within the cell or for secretion outside of the cell. It receives these molecules from the endoplasmic reticulum and modifies them by adding sugars or other molecules, and then packages them into vesicles for transport. This process ensures that proteins and lipids are properly sorted and delivered to their intended locations, allowing for proper cell function.

Ionotropic receptors are receptors that, upon receiving the appropriate neurotransmitter, directly activate and open an ion channel. This allows for the rapid flow of ions across the cell membrane, leading to a quick and direct response in the postsynaptic neuron. In contrast, metabotropic receptors do not directly open ion channels but instead activate a series of intracellular signaling pathways. Neurotropic receptors and autoreceptors are not relevant to this concept and do not fit the given description.

Lysosomes are known as the "digestive system" of the cell world because they contain enzymes that break down waste materials and cellular debris. These enzymes help in the process of digestion within the cell, breaking down larger molecules into smaller ones that can be utilized by the cell for energy or eliminated as waste. Just like the digestive system in our body, lysosomes play a crucial role in maintaining the overall health and functioning of the cell.

Potassium is positive, unlike the inside of the cell, so electrostatic pressure keeps it concentrated inside the cell. This means that potassium ions, which have a positive charge, are more likely to be attracted and retained inside the cell due to the electrostatic forces. This concentration gradient of potassium ions across the cell membrane is important for various cellular processes, such as maintaining the cell's resting membrane potential and regulating cell volume.

When the membrane potential is resting at -70mV, the cell is considered polarized. This means that there is a difference in electrical charge between the inside and outside of the cell, with the inside being more negatively charged. This polarization is maintained by the selective permeability of the cell membrane to different ions and the action of ion pumps.

Nodes of Ranvier are essential for the proper functioning of the nervous system. These gaps in the myelinated sheath allow for the regeneration of the action potential, preventing it from losing strength as it travels along the axon. Without nodes of Ranvier, the action potential would gradually weaken, making it difficult for the signal to reach the terminal buttons and activate the necessary response. Therefore, the presence of nodes of Ranvier is crucial for maintaining the strength and efficiency of the action potential along the axon.

The nuclear envelope is a double membrane that surrounds the nucleus, separating it from the rest of the cell. Similarly, the cell membrane is a double layer of phospholipids that surrounds the entire cell, separating it from the external environment. Both the nuclear envelope and the cell membrane serve as barriers that regulate the movement of substances in and out of the cell. Therefore, the relationship between the nuclear envelope and the nucleus is analogous to the relationship between the cell membrane and the entire cell.

The axon hillock is the place where the soma (cell body) and the axon join. The axon hillock is a specialized region of the neuron where the action potential is initiated. It is located at the base of the soma and acts as a junction between the cell body and the axon. This region contains a high concentration of voltage-gated ion channels, which play a crucial role in generating and propagating the electrical signal along the axon.

The correct answer is the Sodium-Potassium pump. The Sodium-Potassium pump is a protein found in the cell membrane that helps maintain the balance of sodium and potassium ions inside and outside the cell. It uses ATP energy to pump three sodium ions out of the cell for every two potassium ions it pumps in. This constant pumping requires a significant amount of energy, accounting for up to 40% of the ATP produced by the cell.

Acetylcholine is the only neurotransmitter that utilizes enzymatic deactivation. This means that after acetylcholine has fulfilled its role in transmitting signals between nerve cells, it is broken down by enzymes called acetylcholinesterases. This enzymatic deactivation is crucial for maintaining proper neurotransmitter balance and preventing excessive stimulation of the nervous system. GABA, dopamine, and serotonin are neurotransmitters that are deactivated through different mechanisms, such as reuptake or enzymatic breakdown by other enzymes. Therefore, acetylcholine stands out as the only neurotransmitter that relies on enzymatic deactivation.

Nucleolus chromatin refers to the DNA/protein combinations that are condensed for size and are involved in mitosis/meiosis. The nucleolus is a substructure within the nucleus of a cell, and chromatin is the material that makes up chromosomes. During mitosis and meiosis, the nucleolus chromatin undergoes condensation and organization to form chromosomes, which are then distributed to daughter cells. Therefore, nucleolus chromatin is the correct answer in this context.

Dendrites are the branching extensions of neurons that receive electrical signals from other neurons and transmit them towards the cell body (soma). Axons, on the other hand, are the long projections of neurons that transmit electrical signals away from the cell body towards other neurons or muscles. In this analogy, the relationship between dendrites and axons is similar to the relationship between input and output, as dendrites receive signals (input) and axons transmit signals (output). Therefore, the correct answer is Dendrites; axons.

The correct answer is multipolar; one; many. In a multipolar neuron, there is one axon and many dendrites. This type of neuron is the most common configuration found in the nervous system. The axon carries signals away from the cell body, while the dendrites receive signals from other neurons and transmit them to the cell body.

Microglia are a type of immune cells found in the central nervous system. Their main function is to act as phagocytes, which means they engulf and digest dead or dying neurons, as well as other cellular debris. This process helps to remove waste and maintain the overall health of the nervous system. Therefore, microglia serve as phagocytes eating dead and dying neurons.

Steroid hormones being lipids allows them to pass through the cell membrane easily due to their hydrophobic nature. This enables them to enter the cell and directly reach the nucleus, where they can bind to specific receptors and regulate gene expression. This direct access to the nucleus allows steroid hormones to have a rapid and direct effect on cellular processes, without the need for complex signaling pathways.

Anterograde axoplasmic transport refers to the movement of substances in a neuron away from the cell body towards the terminal buttons. This transport mechanism is responsible for delivering various molecules, proteins, and organelles necessary for synaptic communication and neurotransmitter release at the terminal buttons.

The postsynaptic membrane is the membrane of a neuron that receives signals from the presynaptic neuron. It is responsible for converting these signals into electrical impulses that can be transmitted throughout the neuron. The nucleus, on the other hand, is the central organelle of a cell that contains the genetic material. It is involved in the control of cell activities and the production of proteins. Therefore, the postsynaptic membrane cannot be a nucleus as it is a separate structure involved in different functions.

Filaments form the skeletal system of the cell world. The skeletal system provides structure and support to the cell, similar to how the skeletal system in humans provides support to the body. Just like bones in the human body, filaments in the cell world help maintain the shape and integrity of the cell. They also play a role in cell movement and provide attachment points for various cellular components. Therefore, the correct answer is skeletal system.

Chlorine is negative, unlike the outside of the cell, so electrostatic pressure keeps it concentrated outside the cell. This means that there is a higher concentration of chlorine ions outside the cell compared to inside. The electrostatic pressure, also known as the electrochemical gradient, helps to maintain this concentration gradient by pushing the negatively charged chlorine ions away from the inside of the cell and keeping them concentrated outside.

Excitatory graded potentials are depolarizing and bring the cell membrane closer to 0mV. This means that they increase the positive charge inside the cell, making it more likely for an action potential to occur.

Autoreceptors are receptors within the cell that respond to neurotransmitters that the cell itself released. These receptors act as a feedback mechanism, regulating the release of neurotransmitters. When the concentration of neurotransmitters reaches a certain level, autoreceptors are activated, reducing further release. This helps maintain a balance in neurotransmitter levels and prevent excessive stimulation. Therefore, autoreceptors play a crucial role in regulating the activity of neurons and maintaining overall neurotransmitter homeostasis.

The smooth endoplasmic reticulum (ER) is responsible for lipid synthesis, detoxification, and carbohydrate metabolism. It lacks ribosomes, which gives it a smooth appearance. Lipids, such as phospholipids and steroids, are essential components of cell membranes and play a crucial role in various cellular processes. Therefore, comparing the smooth ER to a "lipid factory" accurately describes its function in the cell world.

Schwann cells are a type of glial cell in the peripheral nervous system that play a crucial role in myelination. Myelination refers to the process of forming a protective covering around the axons of neurons. Schwann cells wrap around a single segment of a neuron, forming a myelin sheath. This myelin sheath helps to insulate the neuron, allowing for faster and more efficient transmission of electrical signals along the axon. Therefore, the purpose of Schwann cells is to myelinate a single segment of a neuron.

Metabotropic receptors are a type of receptor that, when activated by the appropriate neurotransmitter, initiate a cascade of events that ultimately leads to the opening of an ion channel in a different location on the cell membrane. Unlike ionotropic receptors, which directly open ion channels upon activation, metabotropic receptors indirectly modulate ion channels through signal transduction pathways. These receptors play a crucial role in regulating neuronal communication and are involved in various physiological processes in the body.

Non-coding ribonucleic acid (ncRNA) is responsible for cutting and splicing messenger RNA to produce a protein. Unlike coding RNA, which directly codes for proteins, ncRNA plays a regulatory role in gene expression. It can bind to messenger RNA and guide the splicing process, ensuring that the correct sections are joined together to form a functional protein. This process is essential for proper protein synthesis and cellular function. DNA carries the genetic information, but it is not directly involved in cutting and splicing mRNA. Phospholipids and carboxyl do not have a role in this process.

When a more intense stimuli is applied, it results in a more intense graded potential. This graded potential, if it reaches the threshold, will trigger an action potential of the same intensity. This means that the strength or magnitude of the action potential does not change, regardless of the intensity of the stimuli.

Glial cell clean up is not an example of postsynaptic potential termination. Postsynaptic potential termination refers to the processes that stop the transmission of signals across the synapse. Reuptake is the process by which neurotransmitters are taken back up into the presynaptic neuron, enzymatic deactivation involves the breakdown of neurotransmitters by enzymes, and the release of AchE (acetylcholinesterase) is responsible for breaking down acetylcholine. However, glial cell clean up refers to the role of glial cells in removing excess neurotransmitters and maintaining the chemical balance in the synapse, but it does not directly terminate postsynaptic potentials.

The blood-brain barrier has differential permeability to allow the area postrema, responsible for vomiting behavior, to detect toxic substances. The area postrema is a specialized region in the brain that detects and responds to toxic substances in the bloodstream. By allowing certain substances to pass through the blood-brain barrier in this region, the body can quickly detect and initiate vomiting as a protective response to prevent further harm from ingesting toxic substances.

Retrograde axoplasmic transport refers to the movement of substances from the terminal buttons towards the soma. This process allows for the recycling of cellular components, removal of waste materials, and delivery of signals from the terminal buttons to the soma. The soma, also known as the cell body, contains the nucleus and other essential organelles necessary for the functioning of the neuron. Therefore, it is the correct answer as substances are pushed towards the soma during retrograde axoplasmic transport.

Anions are negatively charged ions that are present inside the cell. Since they are negatively charged, they have a tendency to move out of the cell. However, the cell membrane is not permeable to anions, meaning that they cannot freely move across it. Therefore, anions want to get out of the cell, but they are unable to do so due to the impermeability of the cell membrane.

Integral membrane proteins are permanently attached to the cell membrane, meaning that they are embedded within the lipid bilayer and cannot be easily removed without disrupting the membrane structure. On the other hand, peripheral membrane proteins are only temporarily attached to the cell membrane, meaning that they can be easily detached and removed from the membrane without disrupting its structure.

Secretory vesicles in the golgi apparatus contain proteins sent by the granular endoplasmic reticulum, and intend to secrete proteins to outside of the cell.

Neuromodulators are different from neurotransmitters because they travel further and disperse more than neurotransmitters. Unlike neurotransmitters, which act locally and have a specific target receptor, neuromodulators can diffuse over longer distances in the brain and affect multiple neurons. This allows them to have a broader impact on neural activity and regulate complex processes such as mood, arousal, and attention.