The Brain, Nervous System, Action Potentials, NTs, Muscular System
A bipolar neuron has one axon projecting from it and one dendrite. What's the difference between a bipolar neuron and a multipolar neuron?
A multipolar neuron has multiple dendrites projecting from it.
The ependymal cells create a barrier between the cerebral spinal fluid and the interstitial fluid to limit the movement of large molecules between these spaces. Is this a strong barrier or a leaky barrier? Why is this useful for a physician or a researcher?
This is a leaky barrier. And it's important that it is, as it allows us to sample cerebrospinal fluid and analyze it in a laboratory. This usually can give us a lot of information about the tissues in the brain .
Match the parts of the neuron structure to the function. (A) Axon (B) Dendrites (C) Soma (D) Nodes of Ranvier (E) Myelin Sheath (1) Cell's life support center (2) Receive messages from other cells (3) Passes message away from cell body to other neurons (4) Helps speed neural impulse (5) Gaps between myelin sheath, help conduction of nerve impulses
(A) Axon -- (3) Passes message away from cell body to other neurons (B) Dendrites -- (2) Receive messages from other cells (C) Soma -- (1) Cell's life support center (D) Nodes of Ranvier -- (5) Gaps between myelin sheath, help conduction of nerve impulses (E) Myelin Sheath -- (4) Helps speed neural impulse
Heart beat and breathing are controlled by which brain structure? (A) Brainstem (B) Cerebellum (C) Reticular Formations (D) Thalamus
(A) Brainstem Heart beat and breathing are controlled by the Brainstem.
Match the Neuron & Glial cell location to the location it was derived from. (A) CNS (B) PNS (1) Neural Crest Cells (2) Neural Stem Cells
(A) CNS - Neural stem cells (B) PNS - Neural crest cells Neurons and Glial cells from the CNS are derived from the neural stem cells, whereas in the PNS, they are derived from neural crest cells.
Which of the following voltage-gated channel is present at the axon terminal that aids in neurotransmitter release? (A) Ca2+ (B) Ca+ (C) K+ (D) Na+
(A) Ca2+ Calcium voltage channels are present at the axon terminal. Remember, Calcium is a 2+ charge and not 1+.
Which of the following structures is responsible for controlling higher level cognitive thinking and functioning? Where in the brain is it found + specifically? (A) Cerebral cortex (B) Midbrain (C) Hypothalamus (D) Cerebrum (E) Cerebellum
(A) Cerebral cortex The cerebral cortex is part of the cerebrum - found in the telencephalon of the forebrain - controls high level cognitive functioning.
If we're looking at the brain from the top, what major part will we see (the most superficial part)? (A) Cerebrum (B) Midbrain (C) Medulla (D) Brain Stem
(A) Cerebrum The *Cerebrum* is the most superficial part of the brain at the top. It is divided into left and right hemispheres.
Which of the following is responsible for controlling general voluntary movements, cognitive thinking and other functions? What part of the brain is it found in + specifically? (A) Cerebrum (B) Hippocampus (C) Hypothalamus (D) Medulla Oblongata (E) Cerebellum
(A) Cerebrum The cerebrum is responsible for controlling voluntary movements, cognitive functioning and more - it is found in the telencephalon of the forebrain.
Which of the following connects the two hemispheres of the brain? What part of the brain is it found in + specifically? (A) Corpus callosum (B) Cerebrum (C) Thalamus (D) Pons (E) Basal ganglia
(A) Corpus callosum The corpus callosum is part of the cerebrum, which connects the two hemispheres of the brain - found in the telencephalon of the forebrain.
If there is a problem with lower motor neurons, what can be seen during the knee-jerk reflex? (A) Diminished Reflex (B) Heightened Reflex (C) Variable Reflex (D) Opposite Reflex
(A) Diminished Reflex If there is a problem with lower motor neurons, a diminished or lost reflex will be observed. A similar effect would be seen if the somatosensory neurons (afferent neurons) were affected too.
Which of the following regions of the brain consists of the motor cortex, prefrontal cortex and Broca's area? (A) Frontal lobe (B) Parietal lobe (C) Occipital lobe (D) Temporal lobe
(A) Frontal lobe The frontal lobe consists of the prefrontal cortex, motor cortex and Broca's area
Which of the following are sites for Hematopoiesis in adults? I. Cancellous Bone II. Compact Bone III. Metaphysis (A) I Only (B) II Only (C) I and II Only (D) I, II, and III Only
(A) I Only Cancellous Bone, also known as Spongy Bone, is the site of Hematopoiesis. In adults, this Hematopoiesis occurs in Red Bone Marrow, which is located in the Epiphysis (NOT the Metaphysis).
Which of the following are parts of the Axial Skeleton? I. Rib Cage II. Skull III. Hip Bones (A) I and II Only (B) II and III Only (C) I and III Only (D) I, II, and III
(A) I and II Only The Axial Skeleton includes the skull, rib cage, hyoid bone and vertebral column. Every other bone is considered a part of the Appendicular Skeleton.
Which of the following are characteristics of Type 1 (slow twitch/red) muscle fibers? I. Red in color II. Slower contractions as compared to type 2 muscle fibers III. Mainly rely on aerobic respiration A) I only B) III only C) I and II only D) I, II and III
D) I, II and III Type 1 (slow twitch) muscle fibers are red in color, they are slow when contracting, and they mainly rely on aerobic respiration.
If we have a high calcium ion concentration inside the muscle cell. The the following steps happen: I) The calcium ions will bond to the Troponin protein II) The tropomyosin proteins will move out of the way III) The myosin heads to crawl along the actin filaments leading the muscle contraction. (A) I only (B) III only (C) II and III only (D) I, II and III
D) I, II and III When the muscle has a high calcium ion concentration all the three steps happen sequentially causing muscle contraction. Under low Ca++, troponin goes back to standard conformation, allowing tropomyosin to block myosin from attaching to or sliding up actin filament.
The somatic nervous system has a motor and sensory divisions, and is responsible for voluntary skeletal movement. Discuss how the sensory division and neurons work.
Sensory neurons accept signals via receptors, which are carried through a signal axon into the dorsal side (back) of the spinal cord. An important note is that the cell body of these sensory neurons is found near but outside the back side of the spinal cord - area known as the *dorsal root ganglia*.
Describe how ion channels are closed and the three states they can exist in.
Sodium ion channels open in response to change in membrane potential, and are also inactivated by them. When Vm (membrane potential) approaches +35mV - sodium channels *inactivated*; have to be brought back to resting potential to be *deinactivated*. Hence, the three states Na channels can exist in are *closed* (before cell reaches threshold and after inactivation reversed); *open* (from threshold to ~35mV); and *inactive* (from +35mV to resting potential).
Match the type of glial cell to its location. (A) Schwann Cells (B) Oligodendrocytes (1) Peripheral Nervous System (2) Central Nervous System
(A) -- 1 Schwann Cells -- Peripheral Nervous System (B) -- 2 Oligodendrocytes -- Central Nervous System
Put the following steps in order,describing the mechanism of an action potential. 1) Threshold potential is reached 2) Hyperpolarization 3) Depolarization 4) Refractory Period 5) Voltage gated Na+ start to open 6) Voltage gated K+ start to open
1 --> 5 --> 3 --> 6 --> 2 --> 4 Threshold potential is reached Voltage gated Na+ start to open Depolarization Voltage gated K+ start to open Hyperpolarization Refractory Period
Match the area of the myofibril with the following descriptions: 1) Has both actin & myosin 2) Only have actin a) I-band b) A-band
1) Has both actin & myosin b) A-band 2) Only have actin a) I-band
Differentiate between the crossing over effect of upper motor neurons for lower motor neurons in the spinal cord and in the brainstem.
A key difference to remember is that in the corticobulbular tract, the signals from upper motor neurons in the brain can be sent to lower motor neurons on both sides of the brainstem, not just the opposite one (unlike in the corticospinal tract)
Active microglia or resting microglia can be analogous to a macrophage?
Active Microglia. They will migrate to areas of inflammation and they're looking for bacteria or foreign cells that are causing an infection. Upon finding a foreign cell, they can release cytotoxic substances (like Reactive oxygen species) which can kill said invasive cells. Disintegrated bacteria are "fed on" by microglia (phagocytosis) for antigenic purposes.
What are the three classifications of neurotransmitters?
Amino acid derivatives Monoamines (/biogenic amines) Peptide NT's
Give an example of an Exoskeleton versus an Endoskeleton.
An Exoskeleton is a skeletal structure located on the outside of the body, like the shells of a lady bug or a turtle. An Endoskeleton is a skeletal structure located on the inside of the body, as in a human and most other mammals.
Which of the following neuroglia are derived from neural stem cells and neural crest cells? Found in the CNS and in the PNS? - Astrocytes - Ependymal cells - Schwann cells - Microglia - Oligodendrocytes - Satellite cells
Astrocytes - neural stem cells, CNS Ependymal cells - neural stem cells, CNS Schwann cells - neural crest cells, PNS Microglia - neural stem cells, CNS Oligodendrocytes - neural stem cells, CNS Satellite cells - neural crest cells, PNS
Which of the following will result in a bigger action potential? A graded potential with summation to -25mV or a graded potential with summation to -45mV?
Both action potentials will be the same, since they have crossed the threshold potential (~-55mV). This is known as the _*all-or-none property of action potentials*_.
Acetylcholine is found in the CNS and PNS - what are its roles?
CNS - linked to attention and arousal; loss of acetylcholine in hippocampus has been linked to Alzheimers PNS - transmits nerve impulses to muscles
When an action potential comes down an axon and reaches the axon terminal, the action potential will change the membrane potential at the axon terminal and open Ca2+ gated voltage channels. Will calcium flow into the membrane or out?
Calcium will flow INTO the membrane, since it is at a higher concentration outside than inside and the inside of the cell is oppositely charged (negatively charged) compared to the extracellular fluid.
Cranial nerves control the ___ and pass out from the ___. Spinal nerves control the ___ and pass out from the ___. Fill in the blank using the following terms: - Skull - Spinal Cord - Limbs & Trunk - Head & Neck
Cranial nerves control the Head & Neck and pass out from the Skull. Spinal nerves control the Limbs & Trunk and pass out from the Spinal Cord.
How is creatine phosphate made?
Creatine + ATP -> creatine phosphate + ADP *Creatine phosphate* is created form creatine and ATP during times of rest. Can be reversed to create ATP from ADP quickly.
What is the condition of Broca's aphasia?
Damage to the Broca's area of the brain, leading to loss or impairment of ability to comprehend and produce speech.
A neuron is at resting potential. To get closer to the threshold potential to fire an action potential, does hyperpolarization or depolarization occur?
Depolarization occurs. Depolarization makes the potential less negative, while hyperpolarization makes the potential more negative.
True or False? In the Central Nervous System the myelin sheath cells are also called Schwann cells.
False! Schwann cells = PNS Oligodendrocytes = CNS
A muscle cell, termed a *myocyte*. Describe it in terms of its contents: - sarcoplasm - sarcolemma - transverse tubules - muscle fiber
Each myocyte contains modified cytoplasm just outside the SR, known as *sarcoplasm*. The *sarcolemma* refers to the cell membrane of the muscle cell. Each myocyte also contains myofibrils, which is why another name for a muscle cell is a *muscle fiber* The sarcolemma is capable of propagating an action potential and can distribute that potential to all sarcomeres in a muscle using a system of *transverse tubules (T-tubules)*
Excitatory input causes __________________ (raising the membrane potential from resting potential) making the neuron more likely to fire an action potential. Inhibitory input causes __________________ (lowering the membrane potential from resting potential) making the neuron less likely to fire an action potential.
Excitatory input causes *depolarization* (raising the membrane potential from resting potential) making the neuron more likely to fire an action potential. Inhibitory input causes *hyperpolarization* (lowering the membrane potential from resting potential) making the neuron less likely to fire an action potential.
True or false: An area that needs very fine movements, like the fingers or eyes, will have larger motor units.
False. An area that needs very fine movements, like the fingers or eyes, will have smaller motor units. Smaller motor units allow for more precise control.
True or False? The central nervous system is unable to handle when things are off balance, so an increased amount of potassium ions will not be corrected and will cause neuron malfunction.
False. Astrocytes help maintain a constant homeostasis, especially balancing the concentration of ions within and around neurons.
Match these three brain areas (Forebrain, Midbrain, and Hindbrain) with the following structures: - Cerebrum - Medulla - Midbrain - Cerebellum - Pons
Forebrain -- Cerebrum Midbrain -- Midbrain Hindbrain -- Pons, Medulla, Cerebellum
Identify these neurotransmitters as either excitatory or inhibitory. - GABA - Glutamate - Glycine
Glutamate (+) GABA and Glycine (-) Glutamate is the most common excitatory NT in the entire NS. GABA (in the brain) and Glycine (in the spinal cord) are the most common inhibitory NTs. These are common in so many neurons and neural pathways.
Does The Reticular Formation refer to white matter or grey matter?
Grey matter The Reticular Formation is grey matter scattered throughout the inside the brainstem.
Match the following symptoms with either a Lower Motor Neuron Sign (LMN) or Upper Motor Neuron Sign (UMN) - Hyperreflexia - Hypertonia - Hypotonia - Hyporeflexia
Hypertonia & Hyperreflexia -- UMN Hypotonia & Hyporeflexia - LMN Hyperreflexia is an increase in muscle stretch reflexes; Hypertonia is increase tone of skeletal muscles Hyporeflexia is a decrease in muscle-stretch reflexes; Hypotonia is decrease tone of skeletal muscles
Neurons may be excitatory or inhibitory, and this distinction comes at the level of the neurotransmitter receptor. Distinguish between ligand-gated ion channels and G protein coupled receptors (GPCR)
If the receptor is a ligand-gated ion channel, the postsynaptic cell will be either depolarized or hyperpolarized. If the receptor is a GPCR - causes either changes in [cAMP] or an influx of calcium.
Describe the process of *impulse propogation*, which is the movement of an action potential down an axon to initiate NT release.
Impulse propogation: as sodium rushes into one segment of the axon, it causes depolarization in surronding regions; this depolarization brings subsequent segments of the axon to threshold which opens sodium channels in those segments. Each of these segments continues in wave-like fashion until the nerve terminal is reached, releasing the respective neurotransmitter. This explains why action potentials do not decay with distance, unlike graded potentials. When an action potential fires in one segment of the axon, it becomes momentarily refractory - functionally this means info can only travel in one direction.
The CNS consists of the brain and spinal cord. Describe how they contain grey and white matter and the structuring.
In the brain, white matter lies deeper than the grey matter. The *white matter* consists of axons encased in myelin sheaths, while the *grey matter* consists of unmyelinated cell bodies and dendrites (nuclei). In the spinal cord, white matter lies on the outside of the cord and grey matter is deeper.
The speed at which action potentials move depends on the length and cross-sectional area of the axon, but one of the two has significantly more of an effect. How do these factors influence speed of conduction of action potentials across an axon?
Increased length of an axon results in more resistance and thus slower conduction; however greater cross-sectional area allows for faster propagation due to decreased resistance. The effect of cross sectional area has significantly more of an effect on conduction than axon length.
Describe the process of ion channels opening when the cell is brought to threshold.
Ion channels open in response to change in membrane potential - when the cell is brought to threshold, voltage-gated Na channels open and permit the passage of sodium into the cell via a strong *electrochemical gradient* (electric - interior of the cell is more negative; chemical - [Na] is higher outside the cell - both contribute). As sodium passes through the channels the membrane potential becomes more positive, i.e. cell rapidly depolarizes.
Osteoclasts bone resorption is the breakdown or buildup of bone?
It is the breakdown of bone tissue to release its minerals, thereby releasing calcium from bone to blood.
Skeletal muscles of the right leg controlling movement are predominantly controlled by the right side or the left side of the cerebral cortex?
Left side of the cerebral cortex. Motor movements are generally processed on the contralateral side.
Visual information coming in from the right side of the body is processed on the left side of the cerebral cortex or the right side of the cerebral cortex?
Left side. Visual information is processed on the contralateral side.
What are the long tracts in the nervous system? What do they do?
Long tracts are collections of axons travelling a long distance through the NS and brainstem, connecting the cerebrum to the spinal cord. The long tracts play important roles in motor functions, and consist of motor tracts (upper and lower motor neurons), as well as somatosensory tracts
What about the structure of mechanoreceptors makes it so their action potentials travel faster than nociceptors and thermoreceptors?
Mechanoreceptors have a thicker myelin sheath and a larger axon diameter than nociceptors and thermoreceptors. As we know, myelination and axon diameter are proportional to speed of conduction.
Most of the neural cells are derived from the ectoderm. What makes microglia different? Where are these cells derived from?
Microglia are derived from circulating monocytes from the bone marrow that enter the central nervous system, so they are derived from the mesoderm.
Most people have a prominence of language processing occurring in the left or right hemisphere?
Most people have it in the left hemisphere. Some may have it in the right. (and it is not correlated to handedness)
How does myelination result in faster conduction of action potentials? (hint = describe saltatory conduction!)
Myelin is in most mammalian cells in order to maximise speed of transmission. It is an _extremely good insultator_ and prevents dissipation of electric signal, _such that the membrane is only permeable to ion movement at the *nodes of Ranvier*_ The signal "hops" from node to node - this process is known as *saltatory conduction*
Increased intracellular calcium triggers fusion of membrane-bound vesicles (synaptic vesicles) with the cell membrane at the synapse, causing exocytosis of the neurotransmitter. Describe what happens then
NT's released to the synapse diffuse across the cleft and bind to receptors on the postsynaptic membrane - allows the message to be passed form one neuron to the next.
Astrocytes place their end feet of their processes all over synapses to help clear out synapses of neurotransmitters between neurons. Why is it important to clear out these synapses?
Neurons need to rapidly be able to turn on and off the synapses. If the neurotransmitters just lingered in the area, the synapse would just constantly be turned on.
What two cells are responsible for bone remodelling and maintaining strong bones?
Osteoblasts and osteoclasts. Osteoblasts build bone, and osteoclasts resorb it
Differentiate between multiple bundling of neurons in the PNS and in the CNS.
PNS - nerves and ganglia. CNS - tracts and nuclei Multiple neurons bundled together form a *nerve* in the PNS, which can be sensory, motor or mixed - cell bodies of the same type are clustered together into *ganglia* In the CNS, however, axons may be bundled together to form *tracts*, which carry only one type of information. Cell bodies of neurons in the same tract - groups into *nuclei*.
Describe the difference between afferent neurons and efferent neurons corresponding to the starting and ending locations of PNS & CNS.
Periphery --> CNS: Afferent (sensory) Neuron CNS --> Periphery: Efferent (motor) Neuron
One of the forces that drive ions into or out of the neuron is an electrical force from the membrane potential. During resting potential, describe how these ions will move, either into or out of the membrane. 1) Organic Anions 2) Chlorine 3) Potassium 4) Sodium 5) Calcium
Remembering the charge difference across the neuron will help conceptualize this question. Just outside the neuron the charge is positive, and just inside the neuron the charge is negative. 1) Organic Anions - move out 2) Chlorine - move out 3) Potassium - move in 4) Sodium - move in 5) Calcium - move in
One of the forces that drives ions into or out of the neuron is a chemical force sort of like a diffusion force related to the concentration gradients across the neuron membrane. During resting potential, describe how these ions will move, either into or out of the membrane. 1) Organic Anions 2) Chlorine 3) Potassium 4) Sodium 5) Calcium
Remembering which ions are in majority inside and outside the membrane will help conceptualize this question. In diffusion, ions will go from areas of high concentration to areas of low concentration. 1) Organic Anions - move out 2) Chlorine - move in 3) Potassium - move out 4) Sodium - move in 5) Calcium - move in
Do active microglia or resting microglia have long processes projecting from the soma?
Resting microglia. They are _surveying the area looking for inflammation_. Once they detect it, the long processes retract into the soma, and the microglia becomes a blob-like structure.
In most people, paying attention to both sides of the body and the environment is primarily processed in the right or left cerebral hemisphere?
Right cerebral hemisphere. Right cerebral hemisphere is responsible for processing and paying _attention_ to both sides of the body and the environment in most people. It has additional attention functions compared to the left hemisphere.
Fill in the blanks: Sarcomeres are attached end-to-end to form _____________, which are surrounded by a covering known as the __________________, a modified ER containing high [Ca2+] ions.
Sarcomeres are attached end-to-end to form *myofibrils*, which are surrounded by a covering known as the *sarcoplasmic reticulum (SR)*, a modified ER containing high [Ca2+] ions.
Where are the reticular formations located in the brainstem?
Scattered neurons about through the grey matter inside the brainstem
Pretty much all our senses are controlled contra-laterally - what does this mean?
Senses from the right side of the body are controlled by the left hemisphere of the brain, and senses from the left side of the body are controlled by the right hemisphere of the brain. Smell sense is the only one controlled epsilaterally (same side). Most people are dominant in the left hemisphere.
Will a synapse occurring closer to the trigger zone be more likely to generate an action potential, or does the location not matter at all?
Synapses closer to the trigger zone will experience less decay, so they have a higher chance of producing an action potential. This is because the potential decays with time AND distance, so a potential farther away may have a very high value at the synapse but a lower, decayed one later.
True or false: in muscle reflexes such as the knee jerk reflex, there is an enhanced reflex response due to inhibition of the opposite muscle to that being contracted.
TRUE. While the afferent (somatosensory) neurons excite lower motor neurons (efferent) of the contracting muscle, they also excite inhibitory neurons which inhibit lower motor neurons of the muscle on the opposite side. This results in an enhanced response. Many reflexes have a similarity in how they work, tipping favour of response in one direction.
True or false: myelin is produced by oligodendrocytes in the CNS and Schwann cells in the PNS
TRUE: myelin is produced by *oligodendrocytes* in the CNS and *Schwann cells* in the PNS
The midbrain consists of the mesencephalon - what is the function?
The *midbrain* is situated between the fore- and hindbrain - relays auditory and visual information between them and controls eye movements.
The cerebral cortex has a primary and association components. For the motor functions, basic motor movements are performed by the _______________ cortex, while more complex motor functions such as the planning of movement are done by the _________________ cortex
The cerebral cortex has a primary and association components. For the motor functions, basic motor movements are performed by the *primary* cortex, while more complex motor functions such as the planning of movement are done by the *association* cortex
The corpus callosum is a band of white matter connecting and allowing information to pass between what two structures?
The corpus callosum is a band of white matter connecting and allowing information to pass between the right and left cerebral hemispheres.
The forebrain consists of the telencephalon and diencephalon. Talk about the diencephalon in terms of the thalamus and hypothalamus, and their functions.
The diencephalon consists of the thalamus and hypothalamus, which are key in the endocrine system. The *thalamus* is a relay centre which sends signals to the cerebral cortex. The *hypothalamus* controls the pituitary gland to release hormones
Prolonged tetanus will result in muscle fatigue. What is the difference between tetanus the disease and physiological tetanus?
The disease tetanus includes physiological tetanus as a major clinical feature, but tetanic physiology occurs under normal conditions with simple twitches in succession. The condition MUST include the symptom, but the symptom can be completely normal and cause muscle fatigue.
What are osteocytes?
The empty spaces between lamellar rings are called *lacunae*, which house mature bone cells known as *osteocytes*. The lacunae are linked via tiny channels called *canaliculi* which allow nutrient exchange between osteocytes and the canals.
Compare the gyri and sulci of the cerebral cortex. What is the advantage of them?
The gyri are the protruding ridges, and the grooves on either side of a gyrus are sulci. Having gyri and sulci increases the surface area for more neurons and neural pathways.
The inorganic components of bones (OH-, PO4^3-, Ca^2+) come together to form _________________________ crystals: Ca10(PO4)6(OH)2
The inorganic components of bones (OH-, PO4^3-, Ca^2+) come together to form *hydroxyapatite* crystals: Ca10(PO4)6(OH)2
The hindbrain is the lowest portion of the brain and consists of the metencephalon and myelencephalon. Talk about the metencephalon and the structures found (pons, cerebellum)
The metencephalon has the pons and cerebellum. The *cerebellum* controls motor movement through coordinating precision and timing (not by initiating) - alcohol influences the cerebellum! The *pons* are in front of the cerebellum and relay information from the forebrain to the cerebellum.
What are the parts of the midbrain?
The midbrain, the pons and the medulla
The hindbrain is the lowest portion of the brain and consists of the metencephalon and myelencephalon. Talk about the myelencephalon and the structures found
The myencephalon consists of the *medulla oblangata*. The medulla oblangata connects to the spinal cord and regulates involuntary functions of the ANS such as respiration, heart rate, blood pressure, etc.
What is hematopoiesis?
The production of the cellular components in our blood. RBCs, WBCs and platelets are produced in the bone marrow. *Red marrow* is filled with hematopoietic stem cells, which is responsible for this. In contrast, *yellow marrow* is composed primarily of fat and is relatively inactive.
The strength of bone comes specifically from ________________, which is both dense and strong. The _________________ (or spongy) bone is where hematopoiesis occurs.
The strength of bone comes specifically from *compact bone*, which is both dense and strong. The *cancellous (or spongy) bone* is where hematopoiesis occurs.
How do the para- and sympathetic NS's differ in terms of: - Blood flow - Pupil dilation - Neurotransmitters
The sympathetic nervous system partitions blood flow such that there is more blood pumped to locomotive regions and less to organs, thereby not only promoting ability to 'fight or flight' but also inhibiting digestion and other processes unnecessary under stress. Pupils dilate via sympathetic, constrict via parasympathetic Parasympathetic NS releases acetylcholine from both preganglionic and postganglionic neurons. In the sympathetic, the preganglionic neurons also release acetylcholine, but postganglionic release norepinephrine.
Neurons are not physically connected, just in close proximity in an area called the *synapse* - define the make up of the synapse.
The synapse consists of the nerve terminal, the postsynaptic membrane (of the other neuron/target), and the *synaptic cleft* (space in between the two). NTs from the axon terminal transverse the synaptic cleft and bind to receptors on the postsynaptic neuron.
How are action potentials able to survive a particularly long axon? Won't they decay like graded potentials?
This is one the differences between graded potentials and action potentials. Action potentials will NOT decay throughout the length of the axon; They remain unchanged.
True or false: cardiac muscles share characteristics of both smooth and skeletal muscles.
True! Cardiac muscles are under autonomic, involuntary control like smooth muscles, but at the same time they are striated like skeletal muscle.
When exercising, a persons heart rate and respiratory rate increase to move more oxygen to the muscles, and the oxyhemoglobin curve shifts to the right in the presence of increase [CO2], increased [H+] (decreased pH), and increased temperature. What happens when muscle use overwhelms the ability of the body to efficiently deliver oxygen?
Under these conditions, even the slow-twitch (red) muscle fibers switch to anaerobic respiration, where lactic acid is produced and the muscle begins to fatigue as a result. The difference between amount of oxygen needed and actual amount present is called *oxygen debt*.
For the most part, how much consciousness is involved in the autonomic nervous system?
Very little to none. All these jobs are done without us "telling" the body to do it.
A particular corticospinal tract starts on the right side of the cortex. If there is dysfunction on the right side of the cerebral hemisphere/brain stem, will weakness of muscle show up on the right side or left side of the body?
Weakness will show up on the Left side of the body. The tract switches direction before the spinal cord, so muscle weakness will show up on the opposite side of the cortex dysfunction.
Is Broca's Area or Wernike's Area responsible for language reception and language comprehension? Is Broca's Area or Wernike's Area responsible for speech production?
Wernike's Area is responsible for language reception and language comprehension - temporal lobe Broca's Area is responsible for speech production - frontal lobe
Are the long tracts of the brainstem that connect different parts of the nervous system composed of white matter or grey matter?
White Matter - Think about the myelin of long axons being white.
Is is possible for two graded potentials to occur (not simultaneously) that will not affect one another?
Yes. Since potentials decay with time and distance, it's possible for one potential to return back to resting state before the second one is fired.
In between the presynaptic neuron and postsynaptic neuron, there is a synaptic cleft. If a neuron signals to a gland or muscle rather than another neuron, the postsynaptic cell is called an __________________
effector
It is more than unideal to have constant signaling to postsynaptic cells, and thus NTs have to be removed from the synaptic cleft. What are the three mechanisms of regulating neurotransmission?
(1) Breaking down of neurotransmitters by enzymatic reactions (e.g. acetylcholine by acetylcholinesterase) (2) *Reuptake carriers* to being NTs back into the presynaptic neuron (e.g. reuptake of serotonin; dopamine and norepinephine also use reuptake carriers) (3) NTs may simply diffuse out of the synaptic cleft (nitrous oxide NO is an e.g.)
Astrocytes respond to any injury in the CNS. Which one of the following actions does NOT occur in the process of repairing the injury. (A) Astrocytes grow to 10x their original size (B) Astrocytes migrate to the site of injury (C) Astrocytes process hypertrophy (D) Astrocytes form a thick tissue called a Glial Scar
(A) Astrocytes grow to 10x their original size Astrocytes themselves do not grow bigger, they proliferate. The rest of the options are all things astrocytes do in response to injury - migration to site, process hypertrophy, and formation of *glial scar* (a thick tissue)
A group of subcortical grey matter nuclei function as a unit, anatomically separated by the internal capsule are collectively called? (A) Basal Ganglia (B) Thalamus (C) Internal Capsule (D) Hypothalamus
(A) Basal Ganglia A group of subcortical grey matter nuclei function as a unit, anatomically separated by the internal capsule are collectively called the Basal Ganglia. Play a major role in motor functions, and also contribute to some cognition and emotion.
Do Afferent Neurons carry information in from the peripheral nervous system to the central nervous system or vice versa? What about Efferent Neurons?
*Afferent Neurons (sensory)* carry information in from the peripheral nervous system to the central nervous system (brain and spinal cord). *Efferent Neurons (motor)* carry information from the central nervous system (brain and spinal cord) to the peripheral nervous system (muscles and glands).
Other cells in the NS function to support neurons. Neurons must be supported and myelinated by other cells - these cells are often called *neuroglia* (aka *glial cells*) - describe briefly the following: - Astrocytes - Ependymal cells - Microglia - Oligodendrocytes/Schwann cells
*Astrocytes* nourish neurons + form blood-brain barrier - controls transmission of solutes from bloodstream to nervous tissue *Ependymal cells* line ventricles of the brain + produce cerebrospinal fluid (physically supports brain + shock absorber) *Microglia* - cells that ingest and breakdown waste products and pathogens in the CNS *Oligodendrocytes* (CNS) and *Schwann cells* (PNS) produce myelin for myelin sheaths.
Describe the following methods of mapping the brain: - Cortical maps - Electroencephalograms (EEGs) - Regional Cerebral Blood Flow (rCBF) - CT (computer technology) scans - PET (positron emission tomography) scans - MRI (magnetic resonance imaging) - fMRI (functional MRI)
*Cortical maps* - use of small electrode to stimulate patient's cortex and record brain activity (sleep, arousal, rage, visual, terror etc.) *EEGs* - electrodes to measure activity of large groups of neurons *rCBF* - detect broad patterns of neural activity based on increased blood flow to diff parts of brain *CT scans* - X rays at different angles processed by computer to create images of the brain *PET scans* - radioactive sugar injected and absorbed, dispersion and uptake through targetted tissue is imaged *MRI* - magnetic fields interact w/ H-dense regions of body *fMRI* - same as MRI except specifically measuring changes in blood flow for mapping
Is the Corticospinal Tract an upper or lower motor neuron? It connects what two regions of the Nervous System?
*Corticospinal Tract* is the upper motor neuron tract that starts from the cerebral cortex and ends in the spinal cord. In the brainstem, the axon of the upper motor neuron crosses and switches direction before entering the spinal cord - this explains why the right side of the brain controls the left side of the body, and left hemisphere of the brain controls the right. See image.
Describe how the following terms relate to a Motor Unit? - Lower Motor Neurons - Skeletal Muscle Cells - Neuromuscular Junction
*Lower Motor Neurons* make contact with Skeletal Muscle Cells, _synapsing at the *Neuromuscular Junction*_. This is what then controls a Motor Unit (a group of skeletal muscle cells innervated by one lower motor neuron).
The autonomic nervous system, be it the sympathetic or para- subdivision, consists of preganglionic and postganglionic neurons. Differentiate.
*Preganglionic neurons* are those that begin at the CNS and extend into the ganglia of the PNS - type of motor neuron. *Postganglionic neurons* - neurons that synapse and connect to the preganglionic neurons coming from the CNS, and extend to the effector organ/cell.
Differentiate between motor and sensory neurons, as well as interneurons. Which ones enter/exit the spinal cord via the ventral/dorsal side?
*Sensory neurons* (afferent) carry signals from a receptor to other neurons/targets - they enter the spinal cord from the back side, known as the dorsal side. *Motor neurons* (efferent) extend from the spinal cord of the CNS into the PNS, carrying electric signals from receptors to the target cell (or effector). They exit from the front of the spinal cord, known as the ventral side. *Interneurons* are neurons which connect other neurons to one another (e.g. sensory to a motor neuron)
Differentiate between temporal and spatial summation.
*Temporal summation* - multiple signals are integrated during a short period of time - number of small excitatory signals firing at the same moment could bring a postsynaptic cell to threshold. *Spatial summation* - additive effects are based on the number and location of incoming signals - large number of inhibitory signals firing directly at the soma will cause more hyperpolarization of the axon hillock than depolarization caused by a few excitatory signals firing on dendrites of a neuron.
What is titin?
*Titin* is another protein that acts as a spring and anchors the actin and myosin filaments together and prevent excessive stretching.
Which of the following are examples of Flat Bones? Long Bones? - Skull - Humerus - Ribs - Femur - Pelvis
- Skull -- Flat - Humerus -- Long - Ribs -- Flat - Femur -- Long - Pelvis -- Flat
Match the following types of cartilage with the location. 1) Hyaline Cartilage 2) Elastic Cartilage 3) Fibrous Cartilage a) pubic symphysis b) outer ear, epiglottis c) larynx, trachea
1) Hyaline Cartilage (articular cartilage) c) larynx, trachea 2) Elastic Cartilage b) outer ear, epiglottis 3) Fibrous Cartilage a) pubic symphysis
Describe the major ion causing the change in potential during the following steps and if the ions are moving into or out. 1) -50mV to +40mV 2) +40mV to -70mV 3) -70mV to -60mV
1) Na+ moves into the cell (this is depolarization) 2) K+ moves out of the cell (this is repolarization) 3) K+ voltage channels close and membrane comes back to resting membrane potential
In a resting membrane neuron, please indicate whether the following ions are in majority on the inside of the membrane or the outside and if they are anions or cations. 1) Organic Anions 2) Chlorine 3) Potassium 4) Sodium 5) Calcium
1) Organic Anions -- Inside (Anions) 2) Chlorine -- Outside (Anions) 3) Potassium -- Inside (Cations) 4) Sodium -- Outside (Cations) 5) Calcium -- Outside (Cations)
What are the three things that can influence the effect of magnitude of force created by muscle?
1) Size of the motor unit - motor units with greater number of muscle cells generate more contractile force 2) # of motor units involved - greater the number, more muscle cells involved = the more force 3) thickness of the muscle cells - more exercise results in more sarcomere units (actin and myosin) inside myofibrils = thicker myofibrils = larger muscle diameter = more force
Match the type of connective tissue to the location. 1) Surrounds fascicle 2) Surrounds muscle fiber a) Endomysium b) Perimysium
1) Surrounds fascicle b) Perimysium 2) Surrounds muscle fiber a) Endomysium
Which of the following is NOT a function The Reticular Formation? (A) Autonomic functions (B) Higher functions of the nervous system (C) Memory (D) Sleep/Wakefulness Cycle regulation
C) Memory The Reticular Formation controls Autonomic functions, Higher functions of the nervous system (cognition, emotion, consciousness) and Sleep/Wakefulness cycle regulation by sending axons projecting up to the cerebrum. Memory is the major function of the Hippocampus.
Muscles require ATP to function, and slow-twictch (red) muscle fibers have many mitochondria and thus use oxidative-phorphorylation to generate lots of ATP. However, this means high [O2] are needed to make that much ATP - what are the two supplemental energy reverse in muscle to combat oxygen debt?
Creatine phosphate Lactic acid via anaerobic respiration
True or false: Na+/K+ ATPase acts to restore not only the resting potential, but also the Na and K gradients that have been partially dissipated by the action potential. It pumps out 3 K+ and pumps in 2Na+
FALSE. Na+/K+ ATPase DOES act to restore not only the resting potential, but also the Na and K gradients that have been partially dissipated by the action potential. However, it pumps _3 Na+ ions OUT_ and _2 K+ ions IN_ (which creates an overall small negative charge inside the cell compared to outside, ~-5mV).
True or false: ATP dissociation is required for releasing the myosin head from the actin, and it's hydrolysis is required to power the powerstroke.
FALSE. ATP dissociation (-> ADP + Pi) is required to provide the energy for the powerstroke, while ATP hydrolysis is required for releasing the myosin head bonded to the actin site.
True or False? Sprouting describes depression neuroplasticity.
False. Sprouting is a term used to describe long-term potentiation, which is an increased response to action potentials of neurons. Long-term potentiation may entail an increased number of branching between axons and dendrites.
True or False? The amount of neurotransmitter released into the synaptic cleft is dependent on the intensity of the action potential that went down the axon.
False. The amount of neurotransmitter released into the synaptic cleft is dependent on the *frequency* of action potentials being fired down the axon of the neuron. Remember, action potentials are all-or-none signals that do not have varying strengths. A higher action potential frequency will cause more openings of the calcium channels to open, more calcium will flow in, and the increased concentration of calcium will cause a greater amount of neurotransmitter release.
True or False? The inner trabeculae of spongy bone, or spongy bone, is to make the bone heavier and more compact.
False. The inner trabeculae of spongy bone, or spongy bone, is to make the bone LIGHTER.
True or False? Troponin is responsible to prevent the Myosin from crawling up the actin
False. Tropomyosin is responsible to prevent Myosin from crawling up the actin. The only way to unblock the actin is for troponin to change its conformation, allowing tropomyosin to move out of the way and expose active sites on the actin.
True or False? Upper motor neurons tracts and somatosensory tracts are important short tracts found passing through the brain stem.
False. Upper motor neurons tracts and somatosensory tracts are LONG tracts connecting the cerebrum and the spinal cord, passing through the brain stem.
Which receptors carry information back to the central nervous system through somatosensory neurons? I. Nociceptors II. Thermoreceptors III. Mechanoreceptors
I, II and III Mechanoreceptors, nociceptors and thermoceptors carry information back to the central nervous system through somatosensory neurons
Contraction of muscle requires a series of coordinated steps that are repeating to induce further shortening, and the process is dependent on ATP and calcium. Describe the initiation of contraction.
Motor (efferent) neurons of the NS communicate with the muscles at a *neuromuscular junction*. The signal travels down the neuron until it reaches the *nerve terminal (synaptic bouton)*, where acetylcholine is released into the synapse. Acetylcholine binds to receptors in the sarcolemma (membrane) to cause depolarization, triggering an action potential which spreads down to the T-tubules. These tubules travel into the muscle tissues of the sarcoplasmic reticulum, ultimately releasing Ca2+ ions. Calcium ions bind to regulatory subunit troponin, causing conformational change and exposing myosin-binding sites on the actin filament.
What is the pathway for a motor signal travelling in the somatic NS?
Motor neuron dendrites and cell body accept signal from spinal cord -> exit through the ventral side (front) -> electrical signal (action potential) carried down a single axon to the axon terminal -> synapses at the neuromuscular junction next to cell membrane of the effector, skeletal muscle -> muscle contraction via release of acetylcholine
*Summation* of multiple signals (excitatory and inhibitory) at the trigger zone caused the membrane potential to increase to -65mV from -75mV. Will an action potential be fired?
No it will not. The membrane potential at the trigger zone needs to be closer to -50mV to reach the threshold potential for an action potential to be fired.
A boy touches a hot plate with his left hand, the brain quickly processes this information and tells the boy to remove his left hand. Does the processing occur on the right side of the cerebral cortex or the left side?
Right side. This was an example of somatosensory information, which is processed on the contralateral side.
True or false: all of the following scenarios will go to the same part and side of the cerebrum. - Cricket ball to your left thigh causing pain - Cricket ball on the left side of your face causing pain - A stroke of your S/O on your left arm
TRUE. All of the following sensations would travel through their respective somatosensory tracts, though through different pathways of switching over, to the right part of the cerebrum. An effect causing a variety of sensations would send signals to the opposite cerebrum through respective pathways, which would then collect before being send to the corresponding hemisphere of the brain. NOTE: An injury to one of the hemispheres of the brain in turn would lead to compromises and sensory loss from the other side of the body!
True or false: many motor units may function together for a smooth and coordinated movement. The amount of motor units for used for a force is proportional to how small or large that force is.
TRUE. Many motor units may function together for a smooth and coordinated movement. The amount of motor units for used for a force is proportional to how small or large that force is. A large force will use more motor units than a small one.
True or false: during contraction, the H-zone, I-band, distance between Z-lines, and distance between M-lines all become smaller, while A-bands remain constant in size.
TRUE: during contraction, the H-zone, I-band, distance between Z-lines, and distance between M-lines all become smaller, while A-bands remain constant in size.
What is the axon hillock?
The *axon hillock* is the area at the end of the cell body where signals from dendrites are transmitted before they continue on. The axon hillock integrates and sums up incoming signals and plays a crucial role in action potentials (transmission of electrical impulses down the axon). If signals are summed as excitatory, an action potential is initiated.
Does the Ventral Tegmental Area or Substantia Nigra send Dopamine to the striatum? This is dysfunctional in patients with what condition?
The Substantia Nigra sends Dopamine to the striatum. There is a dysfunction in this pathway with Parkinson's Patients. The VTA projects and diffuses dopamine to the cerebral cortex; the hypothalamus sends dopamine to the pituitary gland.
Describe the idea of equilibrium potential for one of the above ions.
The equilibrium potential is the membrane potential at which the electrical and chemical forces balance each other out, and there is no net movement of that specific ion in or out of the cell.
Is the internal capsule a band of white matter or grey matter?
The internal capsule is a subcortical band of white matter in between areas of grey matter.
Bone matrix is ordered into structural units called *osteons*, or *Haversian systems*. Describe this arrangement.
The lattice structure of spongy bone is microscopic and consists of bony spicules (points) known as *trabeculae*, where the cavities in between trabeculae are filled with one marrow. Each of the osteons contain concentric circles of bony matrix called *lamellae* surrounding a central channel. Longitudinal channels (parallel) are known as *Haversian canals*, while transfers channels (perpendicular) are called *Volksmann's canals*. These canals contain blood and lymph vessels, and nerve fibers to maintain bone health.
True or False? Tropomyosin is attached to actin with help from Troponin
True. Tropomyosin is attached to actin with help from Troponin These proteins help to regulate the interaction between actin and myosin filaments.
True or False? Nicotinic Acetyl Choline Receptors (nAChRs) are found in the postsynaptic muscle which help muscle cells absorb Sodium.
True. nAChRs are responsible for the absorption of sodium by signaling to open sodium channels.
True or False? Skeletal muscles cells are controlled by lower motor neurons, and upper motor neurons control lower motor neurons
True: Skeletal muscles cells are controlled by lower motor neurons, and upper motor neurons control lower motor neurons
True or false: in the brainstem, nerves coming in from the left side of our body cross at a crossover point to go to the right hemisphere.
True: in the brainstem, nerves coming in from the left side of our body cross at a crossover point to go to the right hemisphere. Contra-lateral control
True or false: myosin filaments are thick, actin filaments are thin.
True
True or false: because muscle fibers are so long, they are multinucleated.
True! Muscle fibers are multinucleated since they are so long!
True or False? A pseudounipolar neuron contains an axon that has split into two branches, one branch goes to the periphery and the other goes into the spinal cord.
True. A pseudounipolar neuron contains an axon that has split into two branches, one branch goes to the periphery and the other goes into the spinal cord.
Is type I collagen present in the organic or inorganic structure of the bone matrix?
Type I collage is present in the organic portion of the bone matrix (osteoid).
Transient membrane potentials, also called graded potentials, can occur at which of the following locations? I. Dendrite II. Soma III. Axon (A) I and II only (B) II and III only (C) I only (D) I, II, and III
(A) I and II only Graded potentials can occur in dendrites and somas. Action potentials occur in the axon.
Which of the following are parts of the brain responsible for the voluntary control of skeletal muscle? I. Cortex II. Spinal Cord III. Brain Stem IV. Sympathetic Ganglia (A) I and II only (B) III and IV only (C) II and III only (D) I and IV only
(A) I and II only The cortex and spinal cord are mainly responsible for the voluntary control of skeletal muscle.
Cardiac muscles are found in: I. The heart II. Blood Vessel III. The Lungs (A) I only (B) II and III only (C) I and III only (D) I, II and III
(A) I only Cardiac muscle cells are only found in the heart
Efferent Motor Neurons control which type of organs? I. Skeletal Muscle II. Smooth Muscle III. Cardiac Muscle (A) I only (B) II only (C) III only (D) I, II, and III
(A) I only Efferent motor neurons control skeletal muscle
Put the process of the spinal nerve roots in order starting with information coming in from the peripheral nervous system to the central nervous system. I. Spinal Nerve Roots in Back II. Efferent Neurons III. Afferent Neurons IV. Spinal Nerve Roots in the Front V. Mixed nerves (A) III > I > II > IV > V (B) III > IV > II > I > V (C) V > IV > II > I > III (D) V > I > II > IV > III
(A) III > I > II > IV > V in order starting with information coming in from the peripheral nervous system to the central nervous system: Afferent Neurons --> Spinal nerve roots in back --> Efferent Neurons --> Spinal nerve roots in front --> Come together in the mixed nerves .
Put the following statements in order describing neuron function starting with a neuron at resting membrane potential. I. Information is fired down the axon. II. Membrane potential at the trigger zone crosses the threshold potential. III. Soma receives excitatory/inhibitory information via dendrites. IV. Release of neurotransmitters. (A) III > II > I > IV (B) III > I > II > IV (C) IV > II > I > III (D) IV > I > II > III
(A) III > II > I > IV The order is as follows: Soma receives excitatory/inhibitory information via dendrites > Membrane potential at trigger zone crosses threshold potential > Information fired down an axon > Release of molecules via neurotransmitters
Potentiation results in an ________________ response in the target cell per action potential reaching the axon; Depression on the other hand, results in ________________ response. (A) Increased, decreased (B) Decreased, increased (C) Increased, no change in (D) No change in, decreased
(A) Increased, decreased
Which part of the brainstem is most similar to the spinal cord in terms of the location of white and grey matter? (A) Medulla (B) Pons (C) Reticular Formation (D) Cerebellum
(A) Medulla Most of the grey matter of the medulla is found on the inside and most of the white matter is found on the outside just as it is arranged in the spinal cord.
To prevent a signal from dying off, the axon of a neuron is insulated with a __________________. The signal thus is able to continue on to the synapse without issue. (A) Myelin sheath (B) Myofibril sheath (C) Schwann cells (D) Oligodendocytes
(A) Myelin sheath
A unipolar neuron has ____ axon(s) projecting from the soma. (A) One (B) Two (C) Three (D) Four
(A) One A unipolar neuron has one axon projecting from the soma, and no dendrites, hence the name UNI-polar. These are most common in humans during development.
These type of cells are precursors to osteoblasts, and develop into osteoblasts under the influence of growth factors. Which type of cells are these? (A) Osteoprogenitors (B) Osteoblasts (C) Osteoclasts (D) Osteocytes
(A) Osteoprogenitors Osteoprogenitors are precursors to osteoblasts.
Actin and Myosin are both types of ________ (A) Proteins (B) Fat (C) Carbohydrate (D) None of the above
(A) Proteins Actin and Myosin are both types of protein which in conjunction with ATP produce mechanical motion.
Which region describes a sarcomere? (A) Region between two Z-lines (B) Region between two H zones (C) Region between two one A bands (D) None of the above
(A) Region between two Z-lines The sarcomere is the region of the myofibril between two Z lines; It is the most basic unit of contraction for the skeletal muscle
Match the neurotransmitter to the collection of neurons that diffuse it through the cerebral cortex. (A) Serotonin (B) Dopamine (C) Glutamate (D) Acetylcholine (E) Norepinephrine (F) Histamine (1) Ventral Tegmental Area (2) Raphe (3) Reticular Activating System (4) Hypothalamus (5) Basalis & Septal Nuclei (6) Locus Ceruleus
(A) Serotonin -- Raphe (B) Dopamine --Ventral Tegmental Area (VTA) (C) Glutamate -- Reticular Activating System (RAS) (D) Acetylcholine -- Basalis & Septal Nuclei (E) Norepinephrine -- Locus Ceruleus (F) Histamine -- Hypothalamus
The _______ of a neuron, aka it's *cell body*, is where the nucleus, ER and ribosomes of the neuron are located. (A) Soma (B) Dendrites (C) Axon (D) Myelin sheath
(A) Soma The *soma* of a neuron, aka it's *cell body*, is where the nucleus, ER and ribosomes of the neuron are located.
These types of joints are found in the the shoulder and hip joint which have many degrees of rotation. They are also found as a sort of hinge joint like an elbow or knee. Which types of joints are these? (A) Synovial (B) Amphiarthroses (C) Synarthroses (D) None of the above
(A) Synovial Synovial joints are the ones found in your hip as well as your knee.
Tim's temporal lobe is removed by a physician. What term best describes this procedure? Which sensory function will he lose? (A) Tissue Removal (B) Neurochemical lesion (C) Cryogenic Blockade (D) Radio Frequency Lesions
(A) Tissue Removal Tim will not be able to hear, as the temporal lobe controls auditory processing.
In the Troponin-complex, which of the following components will bind the calcium? (A) Troponin-C (B) Troponin-I (C) Troponin-D (D) Troponin-T
(A) Troponin-C Troponin-C will bind calcium. Think of that C standing for calcium-binding! Troponin-T = tropomyosin Troponin-I = actin and tropomyosin
Damage to which of the following neuron types can lead to spastic contractions? (A) Upper Motor Neurons (B) Lower Motor Neurons (C) Both Upper and Lower Motor Neurons (D) None of the above
(A) Upper Motor Neurons Damage to the Upper Motor Neurons can prevent the stop signals from reaching Lower Motor Neurons, meaning the latter are free to cause contraction irregularly.
Match the major functions to the lobes of the cerebral cortex. (A) Visual processing (B) Movement, orientation processing (C) Reasoning, planning, problem solving (D) Auditory processing (1) Frontal Lobe (2) Parietal Lobe (3) Occipital Lobe (4) Temporal Lobe
(A) Visual processing -- Occipital Lobe (B) Movement, Orientation -- Parietal Lobe (C) Reasoning, Planning, problem solving -- Frontal Lobe (D) Auditory Processing -- Temporal Lobe
In a resting membrane potential, cations are located right ____________ the membrane, and anions are located right _________ the membrane. (A) outside, inside (B) inside, outside (C) outside, outside (D) inside, inside
(A) outside, inside Cations (positively charged) are located right outside the membrane, and anions (negatively charged) are located right inside the membrane.
Somatosensory neurons for temperature, pain, and some touch have _______ diameter axons with _______ layers of myelin sheath. (A) thin, thin (B) thin, thick (C) thick, thick (D) think, thin
(A) thin, thin Somatosensory neurons for temperature, pain, and some touch have thin diameter axons with thin layers of myelin sheath. Some may have no myelin sheath.
Fill in the blanks: When a sarcomere contracts, the ____-band does not change its length, but the ____-band shortens. (A) A, A (B) A, I (C) I, A (D) I, I
(B) A, I
These types of joints are found in the vertebral joints where are slightly movable. Which types of joints are these? (A) Synovial (B) Amphiarthroses (C) Synarthroses (D) None of the above
(B) Amphiarthroses Amphiarthroses are stiff, but slightly movable like the joints in the vertebral column.
The strength of compact bone comes from the ______________, which has both organic and inorganic components. The organic include collagen, glycoproteins and other peptides, while the inorganic include calcium, phosphate and hydroxide ions. (A) Cartilage (B) Bone matrix (C) Tendons (D) Ligaments
(B) Bone matrix The strength of compact bone comes from the *bone matrix*, which has both organic and inorganic components. The organic include collagen, glycoproteins and other peptides, while the inorganic include calcium, phosphate and hydroxide ions.
What is posterior to the brain stem and connected to the brain stem, and can't be seen if you're looking at the brain from the top? (A) Cerebrum (B) Cerebellum (C) Medulla (D) Brain Stem
(B) Cerebellum The Cerebellum is posterior to the brain stem and connected to the brain stem, and can't be seen if you're looking at the brain from the top.
The ability to run and kick a soccer ball at the same time is due to which brain structure? (A) Medulla (B) Cerebellum (C) Pons (D) Thalamus
(B) Cerebellum The cerebellum is responsible for coordinating movements.
Which of the following is a major function of the Cerebellum? (A) Coordinate thought and actions (B) Coordinate movement (C) Coordinate sensory information (D) Coordinate emotions
(B) Coordinate movement *_Coordinating movement is a major function of the Cerebellum_*. Choice (A) is the cerebrum, which coordinates thoughts and actions (don't confuse cerebrum and cerebellum, very different!) Choice (C) is the thalamus, the sensory relay centre! Choice (D) is the amygdala of the limbic system! (think amygdala = emotions)
The gray matter on the outside of the brain is called _______. The little pockets of gray matter that are found deep in the brain are called ______. (A) Cortex, Cortex (B) Cortex, Nuclei (C) Nuclei, Nuclei (D) Nuclei, Cortex
(B) Cortex, Nuclei The gray matter on the outside of the brain is called *Cortex*. The little pockets of gray matter that are found deep in the brain are called *Nuclei*.
The cell has many appendages emanating directly from the soma called _____________, which receive incoming messengers/signals from other cells. (A) Cell body (B) Dendrites (C) Axon (D) Myelin sheath
(B) Dendrites The cell has many appendages emanating directly from the soma called *dendrites*, which receive incoming messengers/signals from other cells.
Many muscle fibers are packed into cylindrical bundles known as _____________, which are even further packed to form the actual muscle. (A) Myofibrils (B) Fasicles (C) Actin and myosin filaments (D) Motor units
(B) Fasicles
The monoamine class of neurotransmitters play a role in attention, cognition, and emotion. Which of the following is NOT an example of a monoamine neurotransmitter? (A) Serotonin (B) Glycine (C) Histamine (D) Epinephrine/ Norepinephrine
(B) Glycine While glycine is a type of amino acid neurotransmitter, is not a type of monoamine neurotransmitter. Dopamine is another monoamine neurotransmitter.
Which of the following structures is responsible for controlling memories and is part of the limbic system? Where in the brain is it found + specifically? (A) Cerebrum (B) Hippocampus (C) Hypothalamus (D) Medulla Oblongata (E) Cerebellum
(B) Hippocampus The hippocampus controls memories - found in the telencephalon of the forebrain and is buried under the cerebrum.
The soma of lower motor neurons are located in which of the following locations? I. Spinal Cord II. Brain Stem III. Peripheral Nervous System
(B) I and II Only The soma of lower motor neurons are located in the following locations: (1) Spinal Cord (2) Brain Stem
What does the peripheral nervous system contain? I. Nerves II. Ganglia III. Sulci (A) I Only (B) I and II Only (C) II and III Only (D) I, II, and III
(B) I and II Only The two main structures of the peripheral nervous system contains Nerves & Ganglia (contains somas).
Which of the following tests of studying the brain tell us about the brain structure? I. CT Scans II. MRI III. EEG (A) II Only (B) I and II only (C) I and III only (D) II and III only
(B) I and II only CT Scans and MRIs tell us information about the structure of the brain, whereas EEGs tell us information about the functions of the brain.
Which of the following are characteristics of smooth muscles? I. Spindle shaped II. 1 nuclei in the center III. Striated (A) I only (B) I and II only (C) II and III only (D) I, II and III
(B) I and II only Smooth muscles are spindle shaped with only one nuclei in the center.
Efferent Autonomic Neurons control which type of organs? I. Skeletal Muscle & Gland Cells II. Smooth Muscle & Gland Cells III. Cardiac Muscle & Gland Cells (A) I Only (B) II & III Only (C) III Only (D) I and III Only
(B) II & III Only Efferent Autonomic Neurons control cardiac muscle, smooth muscle, and gland cells. Efferent MOTOR neurons control skeletal muscle (I) only.
Order the steps of muscle contraction: I. Calcium ions bind to troponin on the actin to shift tropomyosin and expose myosin-binding sites II. A signal at the synaptic bouton released acetylcholine at a neuromuscular junction III. Acetylcholine binds to receptors on the sarcolemma and causes depolarization IV. A triggered action potential travels down transverse tubules into muscle tissues of the SR to release Ca2+ ions (A) I > II > III > IV (B) II > III > IV > I (C) II > IV > III > I (D) III > II > I > IV
(B) II > III > IV > I 1) A signal at the synaptic bouton released acetylcholine at a neuromuscular junction 2) Acetylcholine binds to receptors on the sarcolemma and causes depolarization 3) A triggered action potential travels down transverse tubules into muscle tissues of the SR to release Ca2+ ions 4) Calcium ions bind to troponin on the actin to shift tropomyosin and expose myosin-binding sites
Which of the following effects will too little calcium in the blood have? I. Lethargy II. Muscle cramps III. Convulsions (A) I and II only (B) II and III only (C) I and III only (D) I, II, and III
(B) II and III only Too little calcium in the blood can lead to muscle cramps and convulsions. Lethargy will be caused too much calcium in the blood.
Which of the following are parts of the brain responsible for the involuntary control of smooth or cardiac muscle? I. Cortex II. Spinal Cord III. Brain Stem IV. Sympathetic Ganglia (A) I and II only (B) III and IV only (C) II and III only (D) I and IV only
(B) III and IV only The brain stem and symptathic ganglia are responsible for the involuntary control of smooth or cardiac muscle.
Which of the following are characteristics of cardiac muscles? I. Spindle shaped II. 1 nuclei in the center III. Branched (A) I only (B) III only (C) II and III only (D) I, II and III
(B) III only Cardiac muscles are branched. The other characteristics describe smooth muscles.
Myelin is rich in which molecules: (A) Carbohydrates (B) Lipids (C) Nucleic Acids (D) All of the above
(B) Lipids
Which of the following is NOT a neurotransmitter? (A) Glycine (B) Lysine (C) Acetylcholine (D) Endorphin
(B) Lysine While there are amino acids which do function as neurotransmitters, Lysine is not one of them. Other neurotransmitters are listed as follows: - Glutamate - GABA - Serotonin - Histamine - Dopamine - Epinephrine/ norepinephrine - Opioids - Acetylcholine
Which of the following is the location of the growth (Epiphyseal) plate? (A) Diaphysis (B) Metaphysis (C) Epiphysis (D) Prephysis
(B) Metaphysis Don't get confused. It is called the EPIphyseal plate, but it is located in the METAphysis!
Which part of the brain stem connects to the cerebrum? (A) Cerebellum (B) Midbrain (C) Medulla (D) Pons
(B) Midbrain The *Midbrain* is the part of the brain stem that connects to the *cerebrum*. Note that the cerebellum does connect to the cerebrum, but is not part of the brain stem!
Which of the following structures is responsible for controlling eye movements and relaying information between the forebrain and hindbrain? (A) Cerebral cortex (B) Midbrain (C) Hypothalamus (D) Cerebrum (E) Cerebellum
(B) Midbrain The midbrain relays auditory and visual info between the forebrain and hindbrain + controls eye movements. It is the only structure of the midbrain.
Each nerve terminal controls a group of myocytes; together, the nerve terminal and its myocytes constitute a ______________. (A) Synaptic vessel (B) Motor unit (C) Motor end plate (D) Myosin junction
(B) Motor unit
The resting membrane potential (i.e. no signal input) describes a neuron with a stable electrical charge difference across their cell membrane where the charge inside the cell is __________, and the charge outside the cell is ____________. (A) Negative, Neutral (B) Negative, Positive (C) Positive, Neutral (D) Positive, Negative
(B) Negative, Positive The resting membrane potential describes a neuron with a stable electrical charge difference across their cell membrane where the charge inside the cell is negative, and the charge outside the cell is positive.
Dr. Al and his lab are working towards finding a cure for Parkinson's Disease. To aid them, they have modeled Parkinson's disease in animals in their lab to target and destroy dopaminergic neurons in the Substantia Nigra. What term best describes this procedure? (A) Tissue Removal (B) Neurochemical lesion (C) Cryogenic Blockade (D) Radio Frequency Lesions
(B) Neurochemical lesion This type of lesion study gives a lot of control, by destroying the cell bodies and very specific populations of neurons within specific areas of the brain. This can be done by using oxidopamine (6-hydroxydopamine), which is very very similar to dopamine structurally, which can kill the neural cells of the area after synaptic reuptake.
Which of the following are periodic gaps in the myelin sheath on the axon of lower motor neurons? (A) Oligodendrocytes (B) Nodes of Ranvier (C) Dendrites (D) Schwann Cells
(B) Nodes of Ranvier The nodes of ranvier are the gaps found in the myelin sheath.
These type of cells synthesize both collagen and protein. In addition, they produce alkaline phosphatase. Which type of cells are these? (A) Osteoprogenitors (B) Osteoblasts (C) Osteoclasts (D) Osteocytes
(B) Osteoblasts Osteoblasts synthesize collagen and protein. Basically they help to build bone. They then mature into the osteocyte.
What is the epimysium? (A) Innermost layer of connective tissue around the muscle cell (B) Outermost layer of connective tissue around the muscle cell (C) Inner most layer of connective tissue around the tendon (D) Outermost layer of connective tissue around the tendon
(B) Outermost layer of connective tissue around the muscle cell *Epimysium* is the outermost layer of connective tissue around the muscle cell
Which of the following regions of the brain consists of the somatosensory cortex and controls spatial manipulation? (A) Frontal lobe (B) Parietal lobe (C) Occipital lobe (D) Temporal lobe
(B) Parietal lobe The parietal lobe consists of the somatosensory cortex and is responsible for spatial control and manipulation.
Which of the following will active microglia secrete in response to foreign cells? (A) Macrophages (B) Reactive Oxygen Species (C) Lymphocytes (D) Lactate
(B) Reactive Oxygen Species Active microglia will secrete ROS substances to destroy foreign cells.
High levels of dopamine is linked to ______________________; loss of dopaminergic neurons is basal ganglia is associated with ___________________ (A) Parkinsons disease, Alzheimer's disease (B) Schizophrenia, Parkinson's disease (C) Depression, mania (D) Schizophrenia, depression
(B) Schizophrenia, Parkinson's disease (Recall dopamine hypothesis of schizophrenia)
Thermoreceptors detect which of the following? (A) Position (B) Temperature (C) Touch (D) Pain
(B) Temperature Thermoreceptors detect temperature.
Which of the following structures is involved in sensory and higher order functions of the brain such as cognition, emotion, and consciousness? (A) Basal Ganglia (B) Thalamus (C) Internal Capsule (D) Hypothalamus
(B) Thalamus The Thalamus is involved in sensory and higher order functions of the brain such as cognition, emotion, and consciousness.
Somatosensory neurons are ______________ neurons which have their soma/cell bodies in _______________ near the spinal cord. (A) efferent, ganglia (B) afferent, ganglia (C) efferent, nuclei (D) afferent, nuclei
(B) afferent, ganglia Somatosensory neurons are *afferent* neurons which have their soma/cell bodies in *ganglia* near the spinal cord.
Neuron Somas are located within _____________. Myelinated Axons are located within _____________. (A) gray matter, gray matter (B) gray matter, white matter (C) white matter, white matter (D) white matter, gray matter
(B) gray matter, white matter Neuron Somas are located within gray matter. Myelinated Axons are located within white matter.
The Parasympathetic nervous system has a _____ first axon, and _____ second axon. (A) long, long (B) long, short (C) short, short (D) short, long
(B) long, short The Parasympathetic nervous system's first neuron has a long first axon, and short second axon.
If the axon hillock receives enough excitatory input to be depolarized to the threshold, an action potential is triggered. What is the usual range for this threshold? (A) -70mV to -65mV (B) 60mV to 80mV (C) -55mV to -40mV (D) -40mV to -25mV
(C) -55mV to -40mV
When a lower motor neuron fires an action potential how many skeletal muscle cells in that motor unit contract? (A) One (B) Some (C) All (D) It depends
(C) All All the skeletal muscle cells in it's unit contract.
High levels of norepinephrine are associated with _______________; low levels are associated with ________________ (A) Anxiety, fear (B) Depression, mania (C) Anxiety and mania, depression (D) Aggression, depression
(C) Anxiety and mania, depression
The __________ is a long appendage/tunnel that terminates in very close proximity to a target structure or molecule, which can be another neuron, a muscle, or a gland. Most mammalian nerve fibers are insulated by _____________ to prevent signal loss. (A) Cell body, oligodendrocytes (B) Dendrites, myelin (C) Axon, myelin (D) Myelin sheath, dendrites
(C) Axon, myelin The *axon* is a long appendage/tunnel that terminates in very close proximity to a target structure or molecule, which can be another neuron, a muscle, or a gland. Most mammalian nerve fibers are insulated by *myelin* to prevent signal loss.
What is the function of the sacroplasmic reticulum? (A) It regulates the calcium ions present inside the muscle cell (B) It acts as the storage for calcium inside muscle cells (C) Both A & B (D) None of the above
(C) Both A & B The sarcoplasmic reticulum acts as a holding place for calcium inside the muscle cells. It also releases and gathers calcium helping in muscle contraction/relaxation
Damage to which of the following neuron types can lead to muscle weakness? (A) Upper Motor Neurons (B) Lower Motor Neurons (C) Both Upper and Lower Motor Neurons (D) None of the above
(C) Both Upper and Lower Motor Neurons Damage to either the Upper or Lower Motor Neurons can lead to muscle weakness.
The nervous system is broken into two parts. What are they? (A) Brain & Peripheral (B) Central & Spinal Cord (C) Central & Peripheral (D) Brain & Spinal Cord
(C) Central & Peripheral The nervous system is broken into the Central and Peripheral Nervous System.
Which of the following describes a synapse that has a gap between it's axon terminal and the membrane of the target cell? (A) Potential (B) Electrical (C) Chemical (D) Kinetic
(C) Chemical A chemical synapse has a gap between it's axon terminal and the membrane of the target cell. The other type of synapse is Electrical, in which there is no gap, and the axon terminal physically connects to the membrane of the target cell. The other answer choices, Potential & Kinetic, are not types of synapses.
Which of the following involves cooling down neurons until they stop firing and functioning? (A) Tissue Removal (B) Neurochemical lesion (C) Cryogenic Blockade (D) Radio Frequency Lesions
(C) Cryogenic Blockade Cryogenic blockade (cortical cooling) - cooling down neurons until they stop firing and functioning.
Which of the following is NOT a primary function of the Skeletal System in humans? (A) Support and provide a framework for movement (B) Protect vital organs (C) Energy Storage (D) Hematopoiesis
(C) Energy Storage The following are the primary functions of the Skeletal System: (1) Support and provide a framework for movement (2) Protect vital organs (3) Calcium Storage (4) Hematopoiesis
Which of the following UMN Signs is also known as the Babinski reflex? (A) Clonus (B) Hypertonia (C) Extensor Plantar Response (D) Hyperreflexia
(C) Extensor Plantar Response The Extensor Plantar Response is an UMN Sign. It is also known as the Babinski reflex.
Which of the following is NOT an Upper Motor Neuron Sign? (A) Clonus (B) Hypertonia (C) Flexor Plantar Response (D) Hyperreflexia
(C) Flexor Plantar Response EXTENSOR Plantar Response is an UMN Sign as well as Clonus (a series of involuntary, rhythmic contractions), Hypertonia, and Hyperreflexia.
Which of the following is not a lower motor neuron sign? (A) Atrophy (B) Fasciculations (C) Hypertonia (D) Hyporeflexia
(C) Hypertonia All of the following are lower motor neuron signs: (1) Atrophy - a loss in muscle mass (2) Fasciculations - involuntary twitches (3) HYPOtonia - a decrease in tone of skeletal muscle (how much remains contracted when trying to relax) (4) Hyporeflexia - decreased muscle stretch reflexes
Which of the following is responsible for controlling the pituitary glands to release hormones? Where in the brain is it considered? (A) Cerebral cortex (B) Midbrain (C) Hypothalamus (D) Cerebrum (E) Cerebellum
(C) Hypothalamus The hypothalamus is found in the diencephalon of the forebrain.
Mechanoreceptors detect which of the following? I. Position II. Vibration III. Pain (A) I Only (B) III Only (C) I and II Only (D) II and III Only
(C) I and II Only Mechanoreceptors detect Position, Vibration, Touch.
Which receptors have bare nerve endings? I. Nociceptors II. Thermoreceptors III. Mechanoreceptors (A) I Only (B) III Only (C) I and II Only (D) I and III Only
(C) I and II Only Nociceptors and Thermoreceptors have bare nerve endings.
Which of the following describe the function of an upper motor neuron? I. Send signal to Lower motor neuron II. Send stop signal to lower motor neuron III. Directly connect with Muscle cells to control muscle contraction (A) I only (B) II only (C) I and II only (D) I, II and III
(C) I and II only Upper motor neurons have two functions: to send the start and stop signals to the lower motor neurons.
When ATP comes and binds with a Myosin head connected with an Action the following happens: I) Myosin releases from Actin II) ATP changes Myosin to low energy confirmation III) The Phosphate released from Myosin causes the Myosin to "push" the Actin filament, also called the "power stroke". (A) I only (B) I and II only (C) I and III only (D) I, II, and III
(C) I and III only When ATP binds with a myosin head, it causes Myosin to release from Actin. Then the ATP changes to ADP and phosphate group which causes the Myosin to change to a HIGH energy conformation. Finally, as the inorganic phoshpate group is released, the Myosin head undergoes a "power stroke" and pushes the actin filament as the myosin returns its head to the low-energy conformation.
Which of the following effects will too much calcium in the blood have? I. Lethargy II. Muscle cramps III. Fatigue (A) I and II only (B) II and III only (C) I and III only (D) I, II, and III
(C) I and III only Too much calcium in the blood will lead to lethargy and fatigue. It will also lead to memory loss. Muscle cramps will result from too little calcium.
Which of the following tests for studying the brain tell us information about the function of the brain? I. CT Scans & MRI II. EEG & MEG III. fMRI & PET (A) I only (B) II only (C) II & III only (D) I & II only
(C) II & III only Both EEG & MEG tell us about the brain function. In addition, fMRI & PET do the same with the added bonus of telling us about the brain structure as well as function.
Which of the following lesion studies can use a temporary change in the brain? I. Tissue Removal II. Cryogenic Blockade III. Neurochemical Lesions (A) III only (B) III and I only (C) II and III only (D) I, II, and III
(C) II and III only Only Cryogenic Blockades and some Neurochemical Lesions can cause a temporary change in the brain for scientist to study the brain.
The corticospinal tract and other important tracts pass through this area of white matter, separating some of the subcortical grey matter nuclei. What area is this? (A) Basal Ganglia (B) Thalamus (C) Internal Capsule (D) Hypothalamus
(C) Internal Capsule The corticospinal tract and other important tracts _pass through the Internal Capsule_, separating some of the subcortical grey matter nuclei.
Oversupply of serotonin is thought to produce _______________; undersupply is thought to produce __________________ (A) Fear, anxiety (B) Depression, mania (C) Mania, depression (D) Anxiety, Schizophrenia
(C) Mania, depression
Which part of the brain stem connects to the spinal cord? (A) Cerebellum (B) Midbrain (C) Medulla (D) Pons
(C) Medulla The *Medulla* is the part of the brain stem that connects to the spinal cord.
In the case for the neuromuscular junction, the nerve terminal/synaptic bouton can also be called the _____________ (A) Synaptic vessel (B) Motor unit (C) Motor end plate (D) Myosin junction
(C) Motor end plate
Which of the following regions of the brain is responsible for visual processing? (A) Frontal lobe (B) Parietal lobe (C) Occipital lobe (D) Temporal lobe
(C) Occipital lobe The occipital lobe is responsible for processing visual processing - may also be referred to as the "striate cortex"
These type of cells are derived from monocytes and are responsible for bone resorption with an enzyme called tartrate resistant acid phosphatase. Which type of cells are these? (A) Osteoprogenitors (B) Osteoblasts (C) Osteoclasts (D) Osteocytes
(C) Osteoclasts Osteoclasts are derived from monocytes and are responsible for bone break down.
Bone remodelling occurs in response to stress, and endocrine hormones such as _____________ may affect bone metabolism by increasing resorption. (A) Aldosterone (B) Testosterone (C) Parathyroid hormone (D) Calcitonin
(C) Parathyroid hormone PTH is released in response to low blood calcium - promotes bone resorption to increase [Ca2+] and [PO4^2-] in the blood. PTH also activates *vitamin D* which promotes bone resorption
If this area of the brain is damaged, the person will go into a coma. What area is this? (A) Brainstem (B) Cerebellum (C) Reticular Formations (D) Thalamus
(C) Reticular Formations If the Reticular Formation is damaged, the person will go into a coma. It's important for our sleep-wake cycles
Synaptic and post-synaptic potentials are caused by ________. Receptor potentials are caused by _________. (A) Stimuli & sensory receptors, Stimuli & sensory receptors (B) Stimuli & sensory receptors, Synapse activity (C) Synapse activity, Stimuli & sensory receptors (D) Synapse activity, Synapse activity
(C) Synapse activity, Stimuli & sensory receptors Synaptic and post-synaptic potentials are caused by synapse activity. Receptor potentials are caused by physical stimuli and sensory receptors.
These types of joints are found in the skull where over time the bones fused together and are now immovable. Which types of joints are these? (A) Synovial (B) Amphiarthroses (C) Synarthroses (D) None of the above
(C) Synarthroses Synarthroses are found in the skull and are *immovable joints*, containing *sutures*.
Somatosensory neurons for position, vibration, and some touch have ______ diameter axons with ______ layers of myelin sheath. (A) thin, thin (B) thin, thick (C) thick, thick (D) think, thin
(C) thick, thick Somatosensory neurons for position, vibration, and some touch have thick diameter axons with thick layers of myelin sheath
The neurotransmitter released by lower motor neurons upon synapsing with muscle cells is: (A) Glutamate (B) Dopamine (C) Norepinephrine (D) Acetylcholine
(D) Acetylcholine
Choose the correct method of clearing out neurotransmitters in the synaptic cleft. (A) Re-uptake pumps in the axon terminal and astrocyte endfeet (B) Diffusion (C) Enzymes (D) All of the above
(D) All of the above All of these are ways neurotransmitters are cleared out of the synaptic cleft.
The central nervous system is also broken down into two parts. What are they? (A) Brain & Peripheral (B) Central & Spinal Cord (C) Central & Peripheral (D) Brain & Spinal Cord
(D) Brain & Spinal Cord The central nervous system is also broken down into two parts: The Brain and Spinal Cord.
What part of the brain attaches onto the spinal cord? (A) Cerebrum (B) Midbrain (C) Medulla (D) Brain Stem
(D) Brain Stem The Brain Stem attaches onto the spinal cord.
The Parasympathetic nervous system's first neuron starts in the ______. The Sympathetic nervous system's first neuron starts in the ______. (A) Middle of the spinal cord, Middle of the spinal cord (B) Middle of the spinal cord, Brain stem & lower spinal cord (C) Brain stem & lower spinal cord, Brain stem & lower spinal cord (D) Brain stem & lower spinal cord, Middle of the spinal cord
(D) Brain stem & lower spinal cord, Middle of the spinal cord The Parasympathetic nervous system's first neuron starts in the Brain stem & lower spinal cord. The Sympathetic nervous system's first neuron starts in the Middle of the spinal cord.
In contrast, peptide hormone _____________ released by the parafollicular cells of the thyroid in response to high blood calcium, promotes bone formation and lowers [Ca2+] in the blood. (A) Aldosterone (B) Testosterone (C) Parathyroid hormone (D) Calcitonin
(D) Calcitonin Peptide hormone *calcitonin* released by the parafollicular cells of the thyroid in response to high blood calcium, promotes bone formation and lowers [Ca2+] in the blood.
The part of the gray matter that is involved in higher cognition is called the ______. The part of the white matter involved in transmitting similar messages long distances in the central nervous system is called a ______. (A) Nuclei, Somatosensory neuron (B) Tract, Nuclei (C) Somatosensory Neuron, Cortex (D) Cortex, Tract
(D) Cortex, Tract The part of the gray matter that is involved in higher cognition is called the Cortex. The part of the white matter involved in transmitting similar messages long distances in the central nervous system is called a Tract.
Mark has been having trouble sleeping at night. He goes into a sleep clinic to get evaluated. Which of the following tests will they use to evaluate his sleeping patterns? (A) PET scans (B) MRI (C) CT Scans (D) EEG
(D) EEG While there is no picture of the brain associated with this, it records sleep patterns. In addition, it can also show if someone had a seizure and engaged in different cognitive tasks.
Which of the following is not a function of microglia? (A) Secrete ROS (B) Phagocytosis of debris (C) Antigen presentation (D) Homeostasis
(D) Homeostasis Homeostasis is not a function of microglia. Rather, homeostasis is an important function of astrocytes.
Which of the following structures is connected to and controls the pituitary gland and plays a major role in controlling the endocrine system? (A) Basal Ganglia (B) Thalamus (C) Internal Capsule (D) Hypothalamus
(D) Hypothalamus The Hypothalamus is connected to and controls the pituitary gland and plays a major role in controlling the endocrine system.
Which of the following correctly matchs the type of amino acid neurotransmitter with its function. I. Glutamate - Excitatory II. GABA - Inhibitory III. Glycine - Excitatory (A) I only (B) II only (C) II and III only (D) I and II only
(D) I and II only While all three amino acids are neurotransmitters, only I and II describe them correctly with their function. Glutamate is mostly excitatory. GABA and Glycine are mostly inhibitory.
The efferent neurons of the autonomic nervous system control which of the following types of cells? I. Smooth muscle cells II. Skeletal muscle cells III. Cardiac muscle cells
(D) I and III Only The efferent neurons of the autonomic nervous system control the following types of cells: - Smooth muscle cells - Cardiac muscle cells - Gland Cells *Skeletal muscle cells are controlled consciously by the somatic nervous system.
Which of the following occurs during muscle relaxation (reversing contraction)? I. Acetylcholine is degraded by the enzyme acetylcholinesterase, terminating the signal and allowing the sarcolemma to repolarize II. Sarcoplasmic reticulum takes up calcium as the signal decays III. ATP binds to the myosin heads to disconnect them from actin filaments (A) I only (B) II and III only (C) I and III only (D) I, II and III
(D) I, II and III All three of these occur and the sarcolemma repolarizes as the signal decays, while the SR gets ready for further contractions.
Which of the following are characteristics of skeletal muscles? I. Long Fibers II. Multiple nuclei III. Striations (A) I only (B) III only (C) II and III only (D) I, II and III
(D) I, II and III Skeletal muscles have long fibers, multiple nuclei, and striations.
Which of the following is present in outer, more compact layer of bone? I. Blood & Lymph vessels II. Haversian canal III. Volkmann's canal
(D) I, II, and III Blood, lymph vessels, haverisan canal, and volkmann's canal are all present in the outer compact layer of bone.
Which of the following channels aid in maintaining the resting membrane potential? I. Na+/K+ ATP Pump II. Cl-/K+ Pump III. Ca2+/Na+ Pump (A) I and II only (B) I and III only (C) I only (D) I, II, and III
(D) I, II, and III All three pumps help maintain the resting membrane potential of about -60mV
A sympathetic nervous system response would likely result in which of the following: I. Increased blood flow to the intestines II. Increased cardiac output III. Increased pupil dilation (A) I Only (B) II Only (C) I and II Only (D) II and III Only
(D) II and III Only A sympathetic nervous system response would likely result in the following: (1) DECREASED blood flow to the intestines (2) Increased cardiac output (3) Increased pupil dilation
Which of the following structures is the only part of the myencephalon of the hindbrain, and connects to the spinal cord to regulate involuntary functions of the autonomic nervous system (i.e. heart rate, respiratory rate, blood pressure)? (A) Cerebrum (B) Hippocampus (C) Hypothalamus (D) Medulla Oblongata (E) Cerebellum
(D) Medulla Oblongata The medulla oblongata connects to the spinal cord and controls involuntary responses of the ANS. Note: The brainstem consists of the midbrain, pons, and medulla
Which of the following has a similar effect to insulation in electrical wires to prevent discharging and maintain the signal within the neuron? (A) Cell body (B) Dendrites (C) Axon (D) Myelin sheath
(D) Myelin sheath The *myelin sheath* maintains the electric signal within one neuron.
These types of cells occupy the empty space into bone and are the mature version of osteoblasts. Which type of cells are these? (A) Osteoprogenitors (B) Osteoblasts (C) Osteoclasts (D) Osteocytes
(D) Osteocytes Osteocytes occupy the lacunae, or the empty space within bone. They also connect with other osteocytes creating a star-like appearance.
Nociceptors detect which of the following? (A) Position (B) Temperature (C) Touch (D) Pain
(D) Pain Nociceptors detect pain
The end feet of Astrocyte processes are plastered over blood vessels of the blood brain barrier to prevent molecules from leaving the bloodstream and entering the brain, unless needed. Which molecule would most likely be prevented by the end feet from entering the brain? (A) Glucose (B) Ketones (C) Sodium Ions (D) Proteins
(D) Proteins The blood brain barrier will allow small molecules such as sugars and ions to pass through while preventing larger molecules such as proteins from entering the brain.
Sam has a brain tumor. To destroy the tumor, wire insulated at the very tip is inserted into the brain. What term best describes this procedure? What will happen to the tissue surrounding the tip of the wire? (A) Tissue Removal (B) Neurochemical lesion (C) Cryogenic Blockade (D) Radio Frequency Lesions
(D) Radio Frequency Lesions In *radio frequency lesions*, a wire tip is inserted into the brain, and the tissue surrounding the tip of the wire will also be destroyed. Intensity and duration can be varied to control size of the deletion.
Which of the following is not a function of Astrocytes? (A) Scaffolding (B) Glial Scar (C) Homeostasis (D) Spinal Cord Barrier
(D) Spinal Cord Barrier
Which of the following regions of the brain is responsible for sound processing, language reception/comprehension and consists of the Wernicke's area? (A) Frontal lobe (B) Parietal lobe (C) Occipital lobe (D) Temporal lobe
(D) Temporal lobe The temporal lobe has the Wernicke's area (responsible for language processing and comprehension) and is responsible for auditory processing.
The Sympathetic nervous system has a _____ first axon, and _____ second axon. (A) long, long (B) long, short (C) short, short (D) short, long
(D) short, long The Sympathetic nervous system has a short first axon, and a long second axon.
Which of the following refers to a collection of neurons responsible for the controlling of voluntary movements? Where in the brain is it specifically found? (A) Corpus callosum (B) Cerebrum (C) Thalamus (D) Pons (E) Basal ganglia
(E) Basal ganglia Basal ganglia - collection of neurons at the base of the forebrain (telencephalon) that controls voluntary movements.
Which of the following structures controls the coordination of timing and precision of motor movements? Where in the brain is it found + specifically? (A) Cerebral cortex (B) Midbrain (C) Hypothalamus (D) Cerebrum (E) Cerebellum
(E) Cerebellum The cerebellum controls timing and precision of motor movements - it is considered part of the metencephalon of the hindbrain. The pons relay info from the forebrain to the cerebellum - also part of the metencephalon
What's the difference between a nucleus and ganglia with respect to the NS?
*Nucleus* refers to a group of cell bodies (neurons) in the CNS. *Ganglia* refers to a collection/group of cell bodies found in the PNS.
Order the depolarization spread in cardiac muscle cells that allows them to maintain their own rhythm through myogenic activity: - Spreads from there on to the bundle of His - Depolarization starts at the sinoatrial (SA) node and spreads via conduction pathways to the atrioventricular (AV) node - Depolarization branches then to the Purkinje fibers
- Depolarization starts at the *sinoatrial (SA) node* and spreads via conduction pathways to the *atrioventricular (AV) node* - Spreads from there on to the *bundle of His* - Depolarization branches then to the *Purkinje fibers*
What is a simple twitch? Describe the periods of a simple twitch (latent, contraction and relaxation periods)
A simple twitch is the response of a single muscle fiber to brief stimulus at or above the threshold. It consists of a latent, contraction and relaxation periods. The *latent period* is the time between reaching the threshold and the onset of contraction - in this time frame, the action potential spreads along the muscle and allows for Ca to be released from the SR. Contraction ensues after, and relaxation thereafter.
Does an excitatory input cause the membrane potential to increase or decrease?
An excitatory input causes the potential to increase (get less negative). The reverse is true for an inhibitory input.
Astrocytes are glial cells derived from neural stem cells. Are they a part of the central nervous system or peripheral nervous system?
Astrocytes are part of the central nervous system. They have terminuses called *end feet* and are workhorses - have more function than most cell types of the NS.
How is homeostasis a function of astrocytes?
Astrocytes maintain a balance of ion and nutrient concentration in the neurons and environment. They also have energy stores of glycogen (unlike neurons, which are dependent on oxygen and glucose for energy), and convert glycogen to lactate which they secrete into the interstitial fluid at times of low energy sources for neurons.
If a muscle fiber is exposed to prolonged and frequent stimulation, it will have insufficient time to relax, and contractions combine to become stronger and more prolonged - this is known as ____________________. When the contractions become so frequent and are unable to relax, this is known as _______________. (A) Tetanus, frequency summation (B) Frequency summation, tetanus
B) Frequency summation, tetanus If a muscle fiber is exposed to prolonged and frequent stimulation, it will have insufficient time to relax, and contractions combine to become stronger and more prolonged - this is known as *frequency summation*. When the contractions become so frequent and are unable to relax, this is known as *tetanus*.
One of the unique characteristics of cardiac muscle is how each cardiac myocyte communicates. Elaborate on intercalated discs and gap junctions to allow this unique communication in cardiac muscle cells.
Cardiac myocytes are connected by *intercalated discs*, which contain many *gap junctions* (connections between cytoplasm of adjacent cells). These gap junctions allow for the flow of ions directly between cells, permitting rapid and coordinated muscle cell depolarization and efficient muscle contraction of cardiac muscle.
Cartilage is softer and more flexible than bone, and consists of an elastic, firm matrix called ________________, secreted by cells called *chondrocytes*. Fetal skeletons are mostly made of cartilage to allow growth.
Cartilage is softer and more flexible than bone, and consists of an elastic, firm matrix called *chondrin*, secreted by cells called *chondrocytes*. Fetal skeletons are mostly made of cartilage to allow adequate growth.
Each oligodendrocyte process forms one segment of myelin on an axon. Can oligodendrocytes myelinate only one axon or multiple axons? What about Schwann Cells?
Each oligodendrocyte can myelinate multiple axons. Schwann cells produce myelin sheath for one axon only. In fact, it can only produce one segment of one axon.
Which NTs are classified as monoamines, as well as catecholamines? Functions?
Epinephrine, norepinephrine and dopamine. Epinephrine (adrenaline) and norepinephrine (noradenaline) are involed in controlling alertness and wakefulness - promote fight or flight mode. Nor- acts at a local level, while epinephrine is released by adrenal medulla to act systemically. Dopamine has an important role in movement and posture - found in high conc in basal ganglia; smooths movements and maintains posture.
True or false: the spinal cord is composed of four divisions: the cervical, thoracic, lumbar and sacral. It is protected by the vetrebral column, has white matter on the inside and grey matter on the outside, accepts signals from the PNS and sends them to the brain (and vice versa), and does not participate in the simple reflex arc.
FALSE. The spinal cord is indeed composed of four divisions: the _cervical_, _thoracic_, _lumbar_ and _sacral_. It is indeed protected by the *vertebral column* (which transmits nerves at the space between adjacent vertebrae), and accepts signals from the PNS and sends them to the brain (and vice versa). HOWEVER, it has _white matter on the outside_ and _grey matter on the inside_ (reverse to the brain), and it does participate in the reflex arc. In fact, reflexes do not even require brain input.
True or false: mechanoreceptors are only found towards the surface, on the skin
FALSE. mechanoreceptors are found in the skin but also deeper in places like the muscles to detect and feel stretch
True or false: Somatosensory neurons sending info regarding touch, position and vibration sensations conduct signals slower than somatosensory neurons sending info regarding touch, pain and temperature.
FALSE: Somatosensory neurons sending info regarding touch, position and vibration sensations conduct signals FASTER than somatosensory neurons sending info regarding touch, pain and temperature.
True or false: The resting membrane potential is not affected equally by all ions because ions have different solubilities.
FALSE: The resting membrane potential is not affected equally by all ions because ions have different PERMEABILITIES. (K pumps are more permeable to K+ than Na pumps are to Na+)
True or false: a motor unit refers to only a motor neuron
FALSE: a motor unit refers to a motor neuron and all the effectors/target muscle cells that particular motor neuron affects
True or false: pain from a cricket ball hitting you in the face travels from nocireceptors through spinal nerves into your brainstem.
FALSE: it will travel from nocireceptors through cranial nerves to the brainstem. Cranial nerves are those that emerge/originate directly from the brain, including the brainstem; 10 or 12, excluding the olfactory and optic nerves (terminal nerves) emerge from the brainstem.
True or false: the only function of myelin is insulation and maintenance of electric signal in the neuron
FALSE: myelin's function is not only insulation, but also to speed up transmission and conduction along the axon. Myelin's speed of conduction is courtesy to small breaks in the myelin sheath with exposed areas of axon membrane called *nodes of Ranvier*, critical for rapid signal conduction.
True or False? Flat Bones are unique from Long Bones in that they contain an inner spongy bone and an outer compact bone.
False. Both Flat Bones and Long Bones contain an inner spongy bone and an outer compact bone.
True or False? Cartilage in not innervated by any nerves but has vasculature.
False. Cartilage in not innervated by any nerves and DOES NOT HAVE vasculature (is avascular)
True or False? Mitochondria are more prevalent in type 2 muscle fibers as compared to type 1 muscle fibers.
False. Mitochondria are more prevalent in type 1 (red) muscle fibers.
True or False? All skeletal muscles are attached to tendons or bones.
False. Not every skeletal muscle is attached to a tendon/bone (e.g: The external oblique muscle). It is rather attached to a different fibrous tissue (aponeurosis).
True or False? Multiple action potentials can be fired at the same time, but no more than four.
False. Only ONE action potential can be fired at a time.
True or False? Skeletal muscles and Smooth muscles are under voluntary control
False. Smooth muscles cannot be controlled voluntarily (i.e. they are autonomic). Skeletal muscles are only types of muscles are under voluntary control (somatic).
True or false: because anaerobic respiration can make more ATP than aerobic respiration, the fast-twitch Type 2 muscle fibers are resistant to fatigue.
False. because anaerobic respiration can make LESS ATP than aerobic respiration, the fast-twitch Type 2 muscle fibers will fatigue easily.
A type of potential passed by the dendrites and soma to the trigger zone is the _same size and duration as the size and duration of the input_. The summation results in a value below the threshold, thus the neuron does not fire and transmit information down the axon. Is this an action or graded potential?
Graded potential. A graded potential's size and duration is proportional to the size and duration of the input. A potential summation that goes _BEYOND the threshold of the trigger zone_ results in firing of an _action potential_ - they are the same size and duration for any particular neuron, and are conducted faster along axons that are larger and myelinated.
Match the calcium homeostasis function with the appropriate hormones that accomplishes this effect. I. Increased osteoclast : osteoblast activity II. Increased osteoblast : osteoclast activity (A) Parathyroid Hormone (B) Calcitonin (C) Calcitriol (vitamin D)
I. Increased osteoclast : osteoblast activity (A) Parathyroid Hormone (C) Calcitriol (vitamin D) II. Increased osteoblast : osteoclast activity (B) Calcitonin Osteoclasts increase the amount of calcium and phosphate in our blood. Osteoblasts increase the amount of calcium and phosphate in our bones. Calcitriol and parathyroid have the same effect of calcium and phosphate levels.
In the nervous system, neurons of the CNS are physically supported and provided nutrients by _________________, whereas those of the PNS are supported by _________________.
In the nervous system, neurons of the CNS are physically supported and provided nutrients by *astrocytes*, whereas those of the PNS are supported by *satellite cells*. Astrocytes provide support to neurons in the CNS, holding them in place, and also connect them to blood supply + maintain ion and nutrient conc. outside the neuron. Satellite cells provide protection and support to neurons in the PNS, as well as nutrients
For a reflex, like the knee-jerk reflex, how is the cerebrum involved?
It is not involved. Reflexes are responses to stimuli that don't require consciousness or brain input, only spinal cord. It will register sensations such as pain and temperature from touching a hot stove, but will not be involved in the muscle reflex of withdrawal (or knee jerk for its case)
Between EEG & MEG, one has a better resolution, but also requires a lot of set up and a separate room, so it's usually not used as much. Which one is that?
MEG uses SQUIDS, which has a better resolution than EEG, but it also requires a lot of set up and a separate room. For this reason, EEG are used more often.
Do myelinated or unmyelinated axons experience saltatory conduction?
MYELINATED AXONS! The gaps between the myelin are called the nodes of ranvier. The action potential will move slower in those gaps, and faster in the myelinated regions. This creates a bit of a hop or leap along the axon. This describes saltatory conduction.
The somatic nervous system has a motor and sensory divisions, and is responsible for voluntary skeletal movement. Discuss how the motor division and neurons work.
Motor neurons accept signals from the CNS and send them via efferent fibers to the effector (target) - in the case of the somatic NS, dendrites and cell body of a motor neuron originate in the spinal cord, and the signal is sent down to the axon terminal to the effector, which is always skeletal muscle. Acetylcholine is the NT used to initiate muscle contraction
Muscle cells have many fibres known as myofibrils - what are they and what do they consist of?
Myofibrils are elongated contractile threads found in straited muscle cells, and consist of sarcomere units, which have actin and myosin proteins.
After calcium binds to troponin and exposes the myosin binding sites, the myosin head binds to the active sites and causes shortening of the sarcomere. Describe the mechanism of this cross-bridge cycle/sliding filament model.
Myosin heads bind to the exposed sites on the actin filaments - these actin-myosin cross bridges allow myosin to pull on actin, drawing thin filaments towards the M-line and shortening the sarcomere. Myosin binding requries ATP hydrolysis -> ADP + Pi (inorganic phosphate). This release of ADP and Pi in rapid succession provides energy for the powerstroke and results in sliding of the actin filament over the myosin filament. ATP then binds to the myosin head to release it from actin. This ATP is hydrolyzed to allow the myosin head to recock to a position for initiating another cross-bridge cycle. This is known as the *sliding filament model*.
What is neuroplasticity?
Neuroplasticity refers to how the nervous system changes in response to experience; changes in synapses or other parts of neurons - e.g. when forming new memories
The resting membrane potential is said to be about -60mV measured inside of the membrane. Is that the actual membrane potential?
Not necessarily. The outside is referenced as 0mV and the inside is then the difference between the voltage on the outside and the inside. We would need to measure the outside voltage. If the outside voltage was +5mV, then we would say that the actual resting membrane potential is -60mV + 5mV = -55mV.
Describe resting membrane potential, equilibrium potential of potassium and equilibrium potential of sodium.
Potassium ions slowly leak out of the cell (neuron) due to *potassium leak channels*, as the conc of K+ inside the cell is 140mM, compared to 4mM outside. As it leaks, the inside becomes slightly negative, and this forces a balance of each K+ ion pushed into the cell matched with one pulled in - this is called the *equilibrium potential of potassium*, which is ~-90 mV (- because K+ net pushed out). Sodium ions slowly leak into the cell via *sodium leak channels*, as the inside of the cell conc of Na+ is 12mM and outside is 145mM, and the slow leak in leads to build up of electric potential - this is the *equilibrium potential of sodium*, which is ~60mV (+ because sodium pushed in). Neither ion wins the "tug of war" and at resting potential, the balance of -70mV is reached - this is due to the net effect of both K and Na's potentials - *resting membrane potential*
The somatic nervous systems can control reflex arcs pertaining to skeletal muscles. Describe monosynaptic and polysynaptic reflex arcs with respect to an example of each.
Somatic reflex arcs are quick responses that are automatic and involuntary to stimuli. *Monosynaptic reflex arcs* contain only one synapse between a sensory neuron receiving the stimulus and motor neuron controlling movement. The *knee-jerk reflex* is an example. *Polysynaptic reflex arcs* consist of at least one interneuron between the sensory and motor neurons, where multiple movements or functions may be required. An example is the *withdrawal reflex* from stepping on a nail, where not only is pulling away of the foot via hamstring and hip muscles (monosynaptic portion) required, but also balance through the other foot.
True or false: Na+/K+ ATPase continually pumps sodium and potassium back to where they started (K into, Na out of cell) to maintain respective gradients.
TRUE: *Na+/K+ ATPase* continually pumps sodium and potassium back to where they started (K into, Na out of cell) to maintain respective gradients. It pumps out 3 Na+ ions for every 2 K+ ions in
True or false: Positive potential inside the cell not only triggers inactivation of sodium channels, but also triggers potassium channels to open for repolarization.
TRUE: Positive potential inside the cell not only triggers inactivation of sodium channels, but also triggers potassium channels to open for repolarization. Once sodium has depolarized the cell, an electrochemical gradient in favours potassium efflux (out of cell) - driving out K+ ions restores negative membrane potential in the process of *repolarization*.
True or false: fast twitch (white) muscle fibers have fewer mitochondria and rely on glycolysis and fermentation to make ATP under most conditions.
TRUE: fast twitch muscle fibers have fewer mitochondria and rely on glycolysis and fermentation to make ATP under most conditions.
True or false: pain from a cricket ball hitting your left thigh will travel from nocireceptors to spinal nerves and go to the right side of your cerebrum.
TRUE: pain from a cricket ball hitting your left thigh will travel from nocireceptors to spinal nerves and go to the right side of your cerebrum. Recall that spinal nerves will switch sides/cross over, so that one hemisphere of the brain controls and receives input from the opposite side of the body.
True or false: somas of upper motor neurons are found mainly in the cerebral cortex in the cerebrum, and their axons descend down to synapse with lower motor neurons in the brainstem or spinal cord.
TRUE: somas of upper motor neurons are found mainly in the cerebral cortex in the cerebrum, and their axons descend down to synapse with lower motor neurons in the brainstem or spinal cord.
True or false: the midbrain and hindbrain develop earlier to form the most primitive part of the brain, which is the brainstem
TRUE: the midbrain and hindbrain develop earlier to form the most primitive part of the brain, which is the brainstem
True or false: touch sensations travel in both fast and slow somatosensory neurons. Sensations pertaining to precise touch information (fine touch sense) tend to travel in the fast somatosensory neurons.
TRUE: touch sensations travel in both fast and slow somatosensory neurons. Sensations pertaining to precise touch information (fine touch sense) tend to travel in the fast somatosensory neurons.
Tendon and Ligaments connect what to what in respect to muscle and bone?
Tendons connect muscle to bone Ligaments connect bone to bone
The corticobulbar tract connects which two regions of the Nervous System?
The *corticobulbar tract* starts in the Cortex and ends in the Brain Stem. A trick to remember this is that the Brain Stem used to be called the Bulb.
What is the basic unit of the muscle cell?
The *sarcomere* - it is made of thick and thin filaments (myosin, and actin w/ troponin and tropomyosin respectively). Each sarcomere is divided into different lines, zones and bands. *Z-lines* define boundaries of each sarcomere; *M-line* runs down the center of the sarcomere through the middle of the filaments; *I-band* is a region with exclusively thin filaments; The *H-zone* has only thick filaments; *A-band* contains thick filaments in their entirety including overlapping thin filaments.
Describe the breakdown of the nervous system, including the types of neurons found.
The CNS consists of the brain and spinal cord, and only interneurons are found in them- they relay signals between afferent (sensory) and efferent (motor) neurons. The PNS can be subsivided into the autonomic NS (involuntary movements/functions) and the somatic NS (voluntary movements). The autonomic NS is subdivided into the sympathetic NS (arousal) and parasympathetic NS (rest, digest - both have specialized sensory and motor neurons known as pre- and postganglionic neurons
During the knee-jerk muscle reflex, what do the afferent and efferent parts of the reflex do?
The afferent neurons carry information back to the central nervous system. These are the somatosensory neurons. The efferent neuron (lower motor neuron, who's soma is in the spinal cord) is excited by the somatosensory neuron. Then, the efferent neuron's axon will synapse and excite the muscle that was stretched, causing a contraction. The afferent part is the stimulus, the efferent part is the response.
Differentiate between the sympathetic and parasympathetic divisions of the ANS
The autonomic nervous system controls involuntary bodily functions to maintain homeostasis but also respond to stresses. The two subdivisions work antagonistically, or in oppositely. The *parasympathetic NS* is to conserve energy, "rest and digest" - maintain homeostasis via reducing heart rate, constricting the bronchi. Manages digestion by increasing peristalsis and exocrine secretions. The *sympathetic NS* responds to stress and puts the body in arousal, or 'fight or flight' mode - increases heart rate, blood sugar, relaxes bronchi, dilates pupils, increases/decreases blood flow depending on area, releases epinephrine, decreases digestion and peristalsis.
Why does the brianstem have such a complex anatomy despite being such a small structure?
The brainstem is a hub - it connects all parts of the NS together - connects the spinal cord below, with the cerebrum on top, with the cerebellum behind. It also connects most of the cranial nerves (10 of 12, excluding optic and olfactory)
Hyperpolarization has an important function in making a neuron refractory. Describe the two refractory periods.
The efflux of K+ due to electrochemical gradient changes and favouring (repolarization) causes an overshoot of the resting membrane potential, resulting in hyperpolarization. This hyperpolarization has a key function in making a neuron _refractory to further action potentials_. Two refractory periods: Momentarily, the neurons undergo the *absolute refractory period* where no amount of stimulus can cause another action potential; later there is the *relative refractory period* where there must be a _greater than normal_ stimulation to cause an action potential.
The end of the axon, known as the nerve terminal or synaptic bouton (knob), is a structure that is flattened and enlarged - what is the function of this structure?
The end of the axon, known as the *nerve terminal* or *synaptic bouton (knob)*, is a structure that is flattened and enlarged to maximize neurotransmission to the next neuron and ensure proper release of NTs
What happens to the size of nerves as they move distally?
The nerves branch repeatedly to their target locations, and become smaller.
The forebrain consists of the telencephalon and diencephalon. Talk about the telencephalon in terms of the cerebrum, corpus callosum, hippocampus, cerebral cortex and basal ganglia - match each to its function: I. Collection of neurons at the base of the forebrain which controls voluntary movements II. controls emotions, voluntary actions and other functions III. Part of the cerebrum connecting the two hemispheres IV. part of the cerebrum for high cognitive functioning V. part of the limbic system, controls memories
The telencephalon of the forebrain consists of the cerebrum, hippocampus and basal ganglia. The *cerebrum* (II) controls emotions, voluntary actions and other functions. The *corpus callosum* (III) is part of the cerebrum - connexts two hemispheres The *cerebral cortex* (IV) is made of grey matter controls thought process and high level cognitive functioning. The *hippocampus* (V) is found below the cerebrum, is part of the limbic system, and controls memories. The *basal ganglia* (I) are a collection of neurons at the base of the forebrain - control voluntary movements.
Alyssa is a trained science teacher, but started her own company in fashion merchandising and has been in the fashion industry for over 20 years without keeping up to date with science at all. Her son asks her a simple science question about protons and electrons, but she doesn't even know what those terms mean anymore. Is this an example of neural pruning or sprouting?
This scenario describes pruning. When there is a decreased firing of action potentials, there is a decreased response which causes the axon and dendritic branches to lessen. Sometimes even whole neurons can be removed.
True or False? Astrocytes occupy a huge space of the central nervous system and form a majority of structure that makes up the brain and spinal cord.
True. Astrocytes occupy a huge space of the central nervous system and form a majority of structure that makes up the brain and spinal cord. _This is also called a *scaffold*_.
True or False? Both lower motor neuron dysfunction and upper motor neuron dysfunction can cause muscle weakness.
True. Both lower motor neuron dysfunction and upper motor neuron dysfunction can cause muscle weakness.
True or False? Cartilage is a type of connective tissue, and collagen and elastin are components that give cartilage strength and flexibility.
True. Cartilage is a type of connective tissue, and collagen and elastin are components that give cartilage strength and flexibility.
True or false: For the spinal nerve roots, the afferent neurons travel through the posterior spinal nerve roots and the efferent neurons travel through the anterior spinal nerve roots.
True. For the spinal nerve roots, the afferent neurons travel through the posterior spinal nerve roots and the efferent neurons travel through the anterior spinal nerve roots.
True or False? If there is an increase in calcium in the blood, there will also be an increase of phosphate in the blood.
True. If there is an increase in calcium in the blood, there will also be an increase of phosphate in the blood. To remember this, remember the structure of hydroxyapatite!
True or False? While neurons are located all over the CNS and PNS, the specific types of Glial Cells are only found in either the CNS or PNS.
True. Neurons are located throughout the CNS and PNS. Specific types of Glial cells are specific to either the CNS or PNS.
True or false: Serotonin is also classified as a monoamine, and is thought to play roles in mood, eating, sleeping and dreaming.
True. Serotonin is also classified as a monoamine, and is thought to play roles in mood, eating, sleeping and dreaming.
True or False? The cerebellum uses information from the motor plan, position sense, and feedback to coordinate its major function of coordinating movement.
True. The cerebellum uses information from the motor plan, position sense, and feedback to coordinate its major function of coordinating movement.
True or false: the osteoid (organic portion of the bone matrix) is mainly responsible for bone's tensile strength.
True. The osteoid (organic portion of the bone matrix) is mainly responsible for bone's tensile strength.
True or False? The surface of bones that meet up in a joint are lined by a special type of smooth cartilage called "articular cartilage." It is hard to recover articular cartilage if it has been infected or overused because it is avascular.
True. The surface of bones that meet up in a joint are lined by a special type of smooth cartilage called "articular cartilage." It is hard to recover articular cartilage if it has been infected or overused because it is avascular.
True or False? The two main functions of ependymal cells are to provide a leaky barrier between cerebral spinal fluid and interstitial fluid and to secrete cerebral spinal fluid.
True. The two main functions of ependymal cells are to provide a leaky barrier between cerebral spinal fluid and interstitial fluid and to secrete cerebral spinal fluid.
Remember the thalamus is a relay station for sending sensory signals to the cerebral cortex. What is the name of the embryonic structure it develops from?
_Diencephalon_ (part of the forebrain, also consists of hypothalamus). The thalamus's main function is sensory functions - almost all senses travel through the thalamus in pathways where processing occurs, and signals are then sent to cortex. Higher functions such as cognition, emotion and consciousness are also functions of the thalamus as it is connected to many parts of the brain.