Test One Study Guide

Question 1

Glucose enters absorptive cells this way

Answer 1

secondary active transport

Question 2

ATP is hydrolyzed by the same protein that moves a solute against its gradient

Answer 2

primary active transport

Question 3

Oxygen crosses membranes this way

Answer 3

simple diffusion

Question 4

Glucose enters non-absorptive cells this way

Answer 4

facilitated diffusion

Question 5

A general term describing the movement of solutes FOLLOWING their concentration gradient

Answer 5

diffusion

Question 6

A general term describing the movement of solutes AGAINST their concentration gradient

Answer 6

active transport

Question 7

Diffusion of water through an aquaporin (a specific name for facilitated diffusion of water)

Answer 7

osmosis

Question 8

Water moves into cells by osmosis (diffusion of water), which means it moves:
from low to high water concentration, which corresponds to high to low solute concentration
from high to low water concentration, which corresponds to high to low solute concentration.
from low to high water concentration, which corresponds to low to high solute concentration.
from high to low water concentration, which corresponds to low to high solute concentration.

Answer 8

from high to low water concentration, which corresponds to low to high solute concentration.

Question 9

Which of the following statements best describes substrate phosphorylation (SP)?

SP occurs in all cells during glycolysis and the Krebs cycle. During SP, a kinase enzyme removes a phosphate from a molecule and adds it to ADP. Cytochrome oxidase is an enzyme in the electron transport chain.

In the process of SP, reduced coenzymes (NADH and FADH2) are used to create a hydrogen ion (H+) gradient via the electron transport chain that provides the energy to power the addition of a free phosphate to ADP by the enzyme ATP synthase.

Answer 9

SP occurs in all cells during glycolysis and the Krebs cycle. During SP, a kinase enzyme removes a phosphate from a molecule and adds it to ADP. Cytochrome oxidase is an enzyme in the electron transport chain.

Question 10

Which is the correct sequence of events in cellular metabolism?

Electron transport chain followed by the citric acid cycle followed byglycolysis.

Citric acid cycle followed by the electron transport chain followed by glycolysis.

Glycolysis followed by the citric acid cycle followed by the electron transport chain

Glycolysis followed by the electron transport chain followed by the citric acid cycle

Answer 10

Glycolysis followed by the citric acid cycle followed by the electron transport chain

Question 11

Which is the correct statement about lactic acid?

Lactic acid is converted to pyruvate when oxygen is in short supply

Lactic acid is converted to pyruvate when oxygen is abundant.

Lactic acid is formed from pyruvate when oxygen is in short supply

Lactic acid is formed from pyruvate when oxygen is abundant

Answer 11

Lactic acid is formed from pyruvate when oxygen is in short supply

Question 12

Cyanide would affect cellular respiration by:

Inhibiting glycolysis

Inhibiting oxidative phosphorylation

Inhibiting substrate phosphorylation

Answer 12

Inhibiting oxidative phosphorylation

Oxidative phosphorylation occurs when high energy electrons are passed through the electron transport chain to create a hydrogen ion gradient to power ATP synthase. Oxygen is the final acceptor of electrons and H+ ions.

Question 13

If administered quickly, in some cases cyanide antidotes can save a patient but treatment with oxygen alone is ineffective. Why would this be so?

Cyanide prevents the electron transport chain from creating a hydrogen ion gradient, so hydrogen ions and electrons stop moving through ATP synthase and are not available to form water.

Cyanide blocks oxygen transport proteins

Cyanide prevents the electron transport chain from converting oxygen into water so oxygen has already built up to high levels

Answer 13

Cyanide prevents the electron transport chain from creating a hydrogen ion gradient, so hydrogen ions and electrons stop moving through ATP synthase and are not available to form water.

Question 14

The pH scale ranges from 0 to 14. A low numerical pH value is associated with a high concentration of H+ (or low OH-) and a high pH value with a low concentration of H+ (or high OH-). Which statement about pH is correct?

An alkaline solution has a low pH and low concentration of H+

An acidic solution has a high pH and low concentration of H+

An acidic solution has a low pH and high concentration of H+.

Answer 14

An acidic solution has a low pH and high concentration of H+.

Question 15

CO2 + H2O H+ + HCO3-

This is a reversible reaction catalyzed by the enzyme carbonic anhydrase. The more you breathe, the more CO2 you lose from your blood. If you breathe less, or hold your breath, then more CO2 is held in your blood. The Law of Mass Action (Links to an external site.) thus dictates that your rate of breathing influences your plasma pH. Take a look at this short video about the Law of Mass Action, and dust off your knowledge about pH and hydrogen ions to help you answer the following question.

If you hold your breath for an extended period of time, how will the equilibrium of the above reaction shift, and what will happen to your plasma pH?

The reaction will shift to the right, and pH will increase

The reaction will shift to the right, and pH will decrease.

The reaction will shift to the left, and pH will decrease

The reaction will shift to the left, and pH will increase

Answer 15

The reaction will shift to the right, and pH will decrease.

Question 16

Review the notes about anabolic and catabolic reactions in the Metabolism document (Links to an external site.) and choose the correct statement.

The conversion of glucose to glycogen is called glycogenolysis

The conversion of glycogen to glucose is called glycogenesis

The conversion of glucose to glycogen is called glycogenesis

Answer 16

The conversion of glucose to glycogen is called glycogenesis

Question 17

In the fasted state, when you are mobilizing nutrients (catabolic reactions), what should be happening with carbohydrates?

Glucose should be converted to glycogen for storage in the muscles and liver.

Stored glycogen should be broken down and released into the blood for immediate use

Answer 17

Stored glycogen should be broken down and released into the blood for immediate use

Question 18

Which of the following statements is true?

In the fed state, glycogen is converted to glucose by the process of glycogenolysis.

In the fasted state, glycogen is converted to glucose by the process of glycogenolysis.

In the fed state, glycogen is converted to glucose by the process of gluconeogenesis.

In the fasted state, glycogen is converted to glucose by the process of glycogenesis.

Answer 18

In the fasted state, glycogen is converted to glucose by the process of glycogenolysis.

Question 19

If a toxin disabled a protein in the electron transport chain, which of the following would be true?

There would be no ATP formed at all.

Oxygen would build up inside the cell.

The hydrogen ion gradient across the inner mitochondrial membrane would be lost.

Lactic acid production would stop immediately.

The pH inside cells would increase.

Answer 19

The hydrogen ion gradient across the inner mitochondrial membrane would be lost.

Question 20

Glucose enters intestinal epithelial cells by _____________ and exits those same cells by ______________.

secondary active transport; facilitated diffusion

simple diffusion; primary active transport

facilitated diffusion; secondary active transport

simple diffusion; facilitated diffusion

primary active transport; secondary active transport

Answer 20

secondary active transport; facilitated diffusion

Question 21

The primary structure of proteins is held together by:

van der Waals forces

Ionic and hydrogen bonds

ionic bonds

Covalent bonds

Hydrogen bonds

Answer 21

Covalent bonds

Question 22

Which statement is true about metabolism?

Catabolic reactions generate glucose from glycogen when nutrients are in short supply.

Anabolic reactions generate proteins from amino acids when nutrients are in short supply.

Anabolic reactions generate glycogen from glucose when nutrients are in short supply.

Anabolic reactions generate glycogen from amino acids when nutrients are in short supply.

Catabolic reactions generate lipids from fatty acids when nutrients are in short supply.

Answer 22

Catabolic reactions generate glucose from glycogen when nutrients are in short supply.

Question 23

Which of the following enters cells by facilitated diffusion?

lipids

steroids

glucose

carbon dioxide

oxygen

Answer 23

glucose

Question 24

Which of the following does NOT require a membrane protein to cross cellular membranes?

insulin

carbon dioxide

amino acid

glucose

small peptides

Answer 24

carbon dioxide

Question 25

Which of the following is not a function of the plasma membrane? Act as transport molecules for various solutes. Anchor or stabilize the cell membrane. Bind to ligands. Produce energy. Regulate the passage of ions.

Answer 25

Produce energy.

Question 26

This “compartment” holds the smallest proportion of total body water. extracellular fluid interstitial fluid intracellular fluid interstellar fluid plasma

Answer 26

plasma

Question 27

When carbon dioxide leaves any living cell, it must first pass through _____________ before it can enter the blood. the kidneys intracellular fluid sweat glands lymphatic fluid interstitial fluid

Answer 27

interstitial fluid

Question 28

Regarding gene expression, the process of ____________ produces _______________, and occurs in the cytoplasm of cells. transcription; polypeptides translation; mRNA replication; peptides transcription; mRNA translation; polypeptides

Answer 28

translation; polypeptides

Question 29

Cortisol binds with this receptor

Answer 29

glucocorticoid receptor

Question 30

This type of signal travels through the blood to reach its target cell

Answer 30

hormone

Question 31

This type of signal diffuses through the plasma membrane and activates gene expression

Answer 31

steroid

Question 32

Isoprenaline is a drug that is prescribed for an abnormally low heart rate. It binds with the adrenergic receptors on the pacemaker cells of the heart. This drug would be an __________of the receptor

Answer 32

agonist

Question 33

This hormone is released from the anterior pituitary and binds with receptors in the adrenal cortex

Answer 33

adrenocorticotropic hormone

Question 34

This type of control is how EPI/NE and ACh control heart rate

Answer 34

antagonistic control

Question 35

A non-steroid hormone might cause one of these to open

Answer 35

ion channel

Question 36

Epinephrine and norepinephrine bind with this type of receptor

Answer 36

Adrenergic receptor

Question 37

Insulin is the _____________ of the insulin receptor

Answer 37

primary ligand

Question 38

This type of signal influences the same cell that released it

Answer 38

autocrine signal

Question 39

This hormone is released from the posterior pituitary gland and causes conservation of water

Answer 39

Antidiuretic hormone

Question 40

The binding of cortisol with a glucocorticoid receptor on the hypothalamus, reducing the secretion of corticotropin releasing hormone is an example of this process.

Answer 40

negative feedback

Question 41

The normal action of EPI/NE is to increase heart rate. Propranalol is a drug that slows heart rate by binding to beta-adrenergic receptors. This type of drug is an______ of the receptor

Answer 41

antagonist

Question 42

This type of control is how EPI/NE control blood vessel diameter

Answer 42

tonic control

Question 43

This gland releases oxyticin and antidiuretic hormone

Answer 43

posterior pituitary

Question 44

This type of signal diffuses through some interstitial fluid before binding with its receptor

Answer 44

paracrine signal

Question 45

Which of the following signals would be acting as an agonist of the receptor? Tamoxifen blocks the estrogen receptor to prevent estrogen from binding and causing a breast tumor to grow bigger Insulin binds to the insulin receptor, causing a decrease in blood sugar levels. Cortisol binds with the glucocorticoid receptor in the anterior pituitary gland and decreases the secretion of ACTH Albuterol is given to an asthma patient where it binds with beta-adrenergic receptors in the smooth muscle of the bronchioles, making it easier to breathe

Answer 45

Albuterol is given to an asthma patient where it binds with beta-adrenergic receptors in the smooth muscle of the bronchioles, making it easier to breathe

Question 46

Which is the correct sequence of movement for a molecule of carbon dioxide produced by a cell? Intracellular fluid to plasma to interstitial fluid. Interstitial fluid to intracellular fluid to plasma Intracellular fluid to interstitial fluid to plasma. Plasma to interstitial fluid to intracellular fluid.

Answer 46

Intracellular fluid to interstitial fluid to plasma.

Question 47

Three of the following are characteristics of steroids, and one is not. Which trait does NOT describe a steroid? Can only bind with a membrane-bound receptor Receptor is in the cytosol or nucleus, but the steroid-receptor complex activates transcription. Action is slow and sustained. Lipid soluble and able to diffuse through the plasma membrane.

Answer 47

Can only bind with a membrane-bound receptor

Question 48

Which of the following statements is true? To bind with its receptor in the nucleus, insulin must first pass through the cytosol after it leaves the blood. To bind with its receptor on the plasma membrane, insulin must first pass through lymphatic fluid after it leaves the blood. To bind with its receptor in the nucleus, insulin must first pass through interstitial fluid after it leaves the blood. To bind with its receptor on the plasma membrane, insulin must first pass through interstitial fluid after it leaves the blood.

Answer 48

To bind with its receptor on the plasma membrane, insulin must first pass through interstitial fluid after it leaves the blood.

Question 49

``` Choose the hormone category most likely to increase the amount of cAMP in its target cells. Thyroid hormones Steroids Testosterone Proteins ```

Answer 49

Proteins

Question 50

Which of the following is an example of tonic control of a tissue? Insulin is released from the beta cells of the pancreas Islets of Langerhans and causes a reduction in blood sugar. Glucagon is released from the alpha cells of the pancreatic Islets of Langerhans and causes an increase in blood sugar. Epinephrine binds with adrenergic receptors on the pacemaker cells on the heart to increase heart rate and acetylcholine binds with cholinergic receptors on the pacemaker cells to slow it down. Antidiuretic hormone (ADH) binds with receptors on the collecting duct cells of the kidney to cause water to reabsorbed. The amount of water reabsorbed is proportional to how much ADH binds. Epinephrine binds with adrenergic receptors on the bronchioles to open up the airway and acetylcholine binds with cholinergic receptors on the bronchioles to constrict it.

Answer 50

Antidiuretic hormone (ADH) binds with receptors on the collecting duct cells of the kidney to cause water to reabsorbed. The amount of water reabsorbed is proportional to how much ADH binds.

Question 51

Which statement is correct about ligands? An antagonist binds with the same receptor as the primary ligand but invokes the same or an increased cellular response. The primary ligand is the one that decreases the normal cellular response. An agonist binds with the same receptor as the primary ligand, but decreases the cellular response. An agonist binds with the same receptor as the primary ligand but invokes the same or an increased cellular response.

Answer 51

An agonist binds with the same receptor as the primary ligand but invokes the same or an increased cellular response.

Question 52

Which of the following is an example of a mechanism that would terminate, or reduce the amount of cellular activity following a signal’s release? Monoamine oxidase is an enzyme that breaks down epinephrine Isoprenaline, which can bind with beta adrenergic receptors is administered to increase heart rate and force of contraction of the heart. Caffeine inhibits the action of phosphodiesterase (PDE). PDE normally breaks down cAMP, an importat second messenger molecule in cells. Sarin gas poisoning occurs. Sarin gas is an antagonist of acetylcholinesterase which normally breaks down acetylcholine.

Answer 52

Monoamine oxidase is an enzyme that breaks down epinephrine

Question 53

Which is the correct description of the pathway leading to the secretion of cortisol? Secretion of CRH from the hypothalamus leads to secretion of ACTH from the posterior pituitary which leads to secretion of cortisol from the adrenal cortex. Secretion of cortisol from the hypothalamus leads to secretion of ACTH from the anterior pituitary which leads to secretion of CRH from the adrenal cortex. Secretion of CRH from the hypothalamus leads to secretion of ACTH from the anterior pituitary which leads to secretion of cortisol from the adrenal cortex. Secretion of ACTH from the hypothalamus leads to secretion of CRH from the anterior pituitary which leads to secretion of cortisol from the adrenal cortex.

Answer 53

Secretion of CRH from the hypothalamus leads to secretion of ACTH from the anterior pituitary which leads to secretion of cortisol from the adrenal cortex.

Question 54

Which statement correctly describes negative feedback? Cortisol secreted from the adrenal cortex binds with glucocorticoid receptors in the liver, increasing the conversion of glycogen to glucose. In the stress axis, negative feedback happens when ACTH binds with receptors in the adrenal cortex, increasing the amount of cortisol secretion. Cortisol secreted from the adrenal cortex binds with glucocorticoid receptors in the anterior pituitary, increasing the secretion of ACTH. Cortisol secreted from the adrenal cortex binds with glucocorticoid receptors in the hypothalamus, decreasing secretion of CRH.

Answer 54

Cortisol secreted from the adrenal cortex binds with glucocorticoid receptors in the hypothalamus, decreasing secretion of CRH.

Question 55

What pattern of hormone secretion would be observed in a patient with hypercortisolism if the tumor was in her anterior pituitary gland? Assume that the tumor is OVER producing its normal product and the tumor cells do NOT respond to negative feedback signals. high cortisol, but low levels of CRH and ACTH. high CRH, but low levels of ACTH and cortisol. high CRH, ACTH, and cortisol. high ACTH and cortisol, but low levels of CRH.

Answer 55

high ACTH and cortisol, but low levels of CRH.

Question 56

``` The physiological effects of this signal depend on the presence of cholinergic receptors. insulin testosterone epinephrine cortisol acetylcholine ```

Answer 56

acetylcholine

Question 57

A target cell’s response to a hormone is the activation of a second messenger system. Choose the hormone most likely to evoke this response. ``` epinephrine testosterone aldosterone cortisol estradiol ```

Answer 57

epinephrine

Question 58

``` Signals that affect neighboring cells after diffusing through interstitial fluid are: not found in humans paracrine signals endocrine signals autocrine signals ```

Answer 58

paracrine signals

Question 59

``` Regulation of heart rate is an example of [ Select ] control involving [ Select ] signal-receptor combinations. ```

Answer 59

antagonistic, two

Question 60

``` Glucose enters intestinal epithelial cells by [ Select ] and exits those same cells by [ Select ] . ```

Answer 60

secondary active transport, facilitated diffusion

Question 61

NON-Steroid hormones can initiate responses in target-cells by activating: a second messenger system only enzymes only ion channels, a second messenger system or an enzyme. ion channels only gene transcription

Answer 61

ion channels, a second messenger system or an enzyme.

Question 62

# Choose the pair that is the correct match of hormone and source. oxytocin – hypothalamic/posterior pituitary axis. cortisol – hypothalamus corticotropin releasing hormone –anterior pituitary antidiuretic hormone –anterior pituitary epinephrine – adrenal cortex

Answer 62

oxytocin – hypothalamic/posterior pituitary axis.

Question 63

Which of the following is the best example of an antagonist? Atenolol binds to β-adrenergic receptors preventing an increase in heart rate. Insulin binds to the insulin receptor and causes glucose transporters to be inserted into the membrane of the cell. A drug that increases the activity of dopamine receptors to treat Parkinson’s disease. Cortisol binds to the glucocorticoid receptor and cause proteolysis. Epinephrine and norepinephrine each bind to α- and β-adrenergic receptors.

Answer 63

Atenolol binds to β-adrenergic receptors preventing an increase in heart rate.

Question 64

Which is the correct order of hormone secretions in the tripartite axis activated by stress? Corticotropin releasing hormone, cortisol; ACTH. Cortisol; corticotropin releasing hormone, ACTH. Corticotropin releasing hormone; ACTH; cortisol. ACTH; cortisol; corticotropin releasing hormone. ACTH; corticotropin releasing hormone; cortisol.

Answer 64

Corticotropin releasing hormone; ACTH; cortisol.

Question 65

Patients that are treated with Prednisone (a synthetic form of cortisol), to control inflammation or reduce other immune functions, experience lower levels of endogenous (made by their own glands) CRH and ACTH. What type of effect is this? agonistic postiive feedback negative feedback

Answer 65

negative feedback

Question 66

The physiological effects of this signal depend on the presence of cholinergic receptors ``` testosterone cortisol insulin epinephrine acetylcholine ```

Answer 66

acetylcholine

Question 67

a target cell's response to a hormone is the activation of a second messenger system. Choose the hormone most likely to evoke this response. ``` cortisol epinephrine estradiol testosterone aldosterone ```

Answer 67

epinephrine

Question 68

signals that affect cells after traveling through the blood are called paracrine signals endocrine signals autocrine signals not found in humans

Answer 68

endocrine signals

Question 69

Regulation of blood vessel diameter by epinephrine at beta adrenergic receptors is an example of _____ control involving _____ signal receptor combinations: ``` tonic, at least two antagonistic, only one tonic, only one synergistic, only one antagonistic, at least two ```

Answer 69

tonic, only one

Question 70

glucose enters the intestinal epithelial cells by ____ and exists those cells by ____. secondary active transport, facilitated diffusion simple diffusion, facilitated diffusion facilitated diffusion, secondary active transport primary active transport, secondary active transport facilitated diffusion, simple diffusion

Answer 70

secondary active transport, facilitated diffusion

Question 71

steroid hormones can initiate responses in target cells by activating ``` ion channels an enzyme or ion channel a second messenger system ion channels, a second messenger system, or an enzyme gene transcription ```

Answer 71

gene transcription

Question 72

# choose the pair that is the correct match of hormone and source cortisol - hypothalamus antidiuretic hormone - hypothalamic/posterior pituitary axis epinephrine - adrenal cortex oxytocin - parasympathetic neurons corticotropin releasing hormone - anterior pituitary

Answer 72

antidiuretic hormone - hypothalamic/posterior pituitary axis

Question 73

which of the following is the best example of an agonist? insulin binds to insulin receptors and causes glucose transporters to be inserted into the membrane of the cell cortisol binds to the glucocorticoid receptor and causes proteolysis epinephrine and norepinephrine each bind to a and b - adrenergic receptors a drug that increases the activity of dopamine receptors to treat parkinson's disease atenolol binds to b adrenergic receptors preventing an increase in heart rate

Answer 73

a drug that increases the activity of dopamine receptors to treat parkinson's disease

Question 74

which is the correct order of hormone secretions in the tripartite axis activated by stress? corticotropin releasing hormone, cortisol, ACTH Cortisol, corticotropin releasing hormone, ACTH ACTH, cortisol, corticotropin releasing hormone ACTH, corticotropin releasing hormone, cortisol corticotropin releasing hormone, ACTH, cortisol

Answer 74

corticotropin releasing hormone, ACTH, cortisol

Question 75

Patients that are treated with Prednisone (a synthetic form of cortisol), to control inflammation or reduce other immune functions, experience lower levels of endogenous (made by their own glands) CRH and ACTH. This is called _____ effect. a postive feedback an agonistic a negative feedback

Answer 75

a negative feedback

Question 76

Which of the following statements about potassium is false? When a potassium channel is opened potassium enters the cell because there is more potassium outside the cell than inside. When potassium channels open the membrane potential of the cell moves towards -90 mV. Opening of potassium channels causes the membrane potential to become more negative. When a potassium channel is opened potassium leaves the cell because there is more potassium inside the cell than outside.

Answer 76

When a potassium channel is opened potassium enters the cell because there is more potassium outside the cell than inside.

Question 77

Which of the following statements about sodium is false? Opening of sodium channels causes the membrane potential to become more positive When sodium channels open the membrane potential of the cell moves towards +60 mV. When a sodium channel is opened sodium leaves the cell because there is more sodium inside the cell than outside. When a sodium channel is opened sodium enters the cell because there is more sodium outside the cell than inside.

Answer 77

When a sodium channel is opened sodium leaves the cell because there is more sodium inside the cell than outside.

Question 78

When ligand- gated potassium channels open, what is the most likely consequence? Potassium enters the cell a graded hyperpolarization occurs. Potassium leaves the cell a graded depolarization occurs. Potassium leaves the cell a graded hyperpolarization occurs. Potassium enters the cell and a graded depolarization occurs

Answer 78

Potassium leaves the cell a graded hyperpolarization occurs.

Question 79

A drug that causes voltage-gated sodium channels to stay open for an abnormally longer period of time will cause the resting membrane potential of a neuron to be: more negative than normal. less positive than normal. unchanged from normal. more positive than normal.

Answer 79

more positive than normal.

Question 80

Which statement is correct about neurotransmitters? Neurotransmitters are released by endocytosis and demonstrate endocrine signaling when they cross the synapse to bind with their receptor. Neurotransmitters are released by exocytosis and demonstrate paracrine signaling when they cross the synapse to bind with their receptor. Neurotransmitters are released by endocytosis and demonstrate paracrine signaling when they cross the synapse to bind with their receptor. Neurotransmitters are released by exocytosis and demonstrate endocrine signaling when they cross the synapse to bind with their receptor.

Answer 80

Neurotransmitters are released by exocytosis and demonstrate paracrine signaling when they cross the synapse to bind with their receptor.

Question 81

Which of the following signals would be acting as an agonist of the receptor? Albuterol is given to an asthma patient where it binds with beta-adrenergic receptors in the smooth muscle of the bronchioles, making it easier to breathe. Insulin binds to the insulin receptor, causing a decrease in blood sugar levels. Tamoxifen blocks the estrogen receptor to prevent estrogen from binding and causing a breast tumor to grow bigger. Cortisol binds with the glucocorticoid receptor in the anterior pituitary gland and decreases the secretion of ACTH.

Answer 81

Albuterol is given to an asthma patient where it binds with beta-adrenergic receptors in the smooth muscle of the bronchioles, making it easier to breathe.

Question 82

Benzodiazepine is an agonist of the GABAA receptor. When GABA binds with it’s receptor on the dendritic membrane of a neuron it causes ligand-gated chloride channels to open. Which would be true about the consequence of treatment with benzodiazepine? Benzodiazepine would decrease the opening of the chloride channels, increasing the excitability of the neuron. Benzodiazepine would increase the opening of the chloride channels, reducing the excitability of the neuron. Benzodiazepine would decrease the opening of the chloride channels, reducing the excitability of the neuron. Benzodiazepine would increase the opening of the chloride channels, increasing the excitability of the neuron.

Answer 82

Benzodiazepine would increase the opening of the chloride channels, reducing the excitability of the neuron.

Question 83

There are some poison arrow frog toxins that act as antagonists of acetylcholine gated sodium channels. Which would be a consequence of encountering poison arrow frog toxin? Poison arrow frog toxin would decrease the opening of the sodium channels, reducing the excitability of the neuron. Poison arrow frog toxin would decrease the opening of the sodium channels, increasing the excitability of the neuron. Poison arrow frog toxin would increase the opening of the sodium channels, reducing the excitability of the neuron. Poison arrow frog toxin would increase the opening of the sodium channels, increasing the excitability of the neuron.

Answer 83

Poison arrow frog toxin would decrease the opening of the sodium channels, reducing the excitability of the neuron.

Question 84

Which is true about acetylcholinesterase? Acetylcholinesterase is an enzyme that breaks down acetylcholine, thus increasing the amount of acetylcholine in the synapse. Acetylcholinesterase is an enzyme that breaks down acetylcholine, thus reducing the amount of acetylcholine in the synapse.

Answer 84

Acetylcholinesterase is an enzyme that breaks down acetylcholine, thus reducing the amount of acetylcholine in the synapse.

Question 85

Acetylcholinesterase is an enzyme that breaks down acetylcholine at cholinergic synapses. VX nerve toxin binds with acetylcholinesterase, preventing it from breaking down acetylcholine. Which statement best describes the consequence of being poisoned with VX? There would be greater stimulation of nicotinic and muscarinic adrenergic receptors. There would be greater stimulation of nicotinic and muscarinic cholinergic receptors There would be less stimulation of nicotinic and muscarinic cholinergic receptors. There would be less stimulation of nicotinic and muscarinic adrenergic receptors.

Answer 85

There would be greater stimulation of nicotinic and muscarinic cholinergic receptors

Question 86

One last question to make sure that you have the organization of the autonomic neurons straight. Which statement about sympathetic and parasympathetic neurons is true? Epinephrine is released from the post-ganglionic membrane of the post-ganglionic neurons in the sympathetic nervous system. Acetylcholine is released from the pre-synaptic membranes of the post-ganglionic neurons in the sympathetic nervous system. Epinephrine is released from the pre-synaptic membrane of the pre-ganglionic neurons in the sympathetic nervous system. Acetylcholine is released from the post-synaptic membranes of the pre-ganglionic neurons in the sympathetic system Acetylcholine is released from the pre-synaptic membranes of the post-ganglionic neurons in the parasympathetic nervous system

Answer 86

Acetylcholine is released from the pre-synaptic membranes of the post-ganglionic neurons in the parasympathetic nervous system

Question 87

Which of the following is a characteristic of graded potentials? They require a threshold depolarizaton to be initiated. They do NOT decay over distance They are an all-or-none sequence of depolarization and repolarization. They are always of the same duration Variable in strength.

Answer 87

Variable in strength.

Question 88

Neurotransmitters are typically released from the pre-synaptic membrane of neurons into a synapse.

Answer 88

pre-synaptic membrane of neurons

Question 89

The parasympathetic nervous system causes: a decrease in heart rate an increase in heart rate

Answer 89

a decrease in heart rate

Question 90

``` Which of the following is part of an afferent neural pathway? parasympathetic neurons motor neurons sympathetic neurons baroreceptor neurons ADH-secreting neurons ```

Answer 90

baroreceptor neurons

Question 91

``` Delivery of a drug that increases permeability of neuronal membranes to potassium would cause the neurons to: depolarize stay at -70 mV hyperpolarize become more positive ```

Answer 91

hyperpolarize

Question 92

Which statement is true about action potentials? they do not require a threshold level of depolarization to be initiated they are variable in strength they vary in amplitude and duration they decay over short distances they are an all or nothing sequence of delpolarization and repolarization

Answer 92

they are an all or nothing sequence of delpolarization and repolarization

Question 93

neurotransmitters are typically released from the _____ into a synapse endoplasmic reticulum of glands post-synaptic membrane of neurons dendritic membrane pre-synaptic membrane of neurons nucleus of neurons

Answer 93

pre-synaptic membrane of neurons

Question 94

which branch of the autonomic nervous system would cause an increase in heart rate? parasympathetic or sympathetic?

Answer 94

sympathetic

Question 95

delivery of a drug that increases permeability of neuronal membranes to sodium would cause the neurons to: depolarize hyperpolarize become more negative stay at -70 mV

Answer 95

depolarize