Fundamentals Med Physiology

Question 1

The ECF of cells tends to have larger amounts of which two electrolytes?

Answer 1

More Sodium and Chloride outside cell

Question 2

The inside of cell tends to have greater amounts of what two electrolytes?

Answer 2

More potassium and impermeable anions

Question 3

What anion tends to be both inside and outside the cell in mostly balanced amount with a little greater amount OUTside the cell?

Answer 3

HCO‾₃, Bicarbonate is just slightly more on the outside of cell

Question 4

What are the three components of plasma membrane?

Answer 4

40% Protein, 50% phospholipids, 10% carbohydrates

Question 5

What are the two types of membrane transport proteins?

Answer 5

Channels and transporters

Question 6

What are the two types of membrane transporters?

Answer 6

Solute carriers and pumps

Question 7

What are the two types of membrane channels

Answer 7

Ion and water channels

Question 8

What is the main difference between channels and transporters?

Answer 8

Channels move with a concentration gradient while transporters move against, so transporters require energy for use

Question 9

What is the term for movement across the membrane along the concentration gradient with or without a channel?

Answer 9

Passive transport

Question 10

What is the term for passive transport with a channel?

Answer 10

Facilitated diffusion

Question 11

Which type of transporter can be either passive or active transport?

Answer 11

Solute carrier

Question 12

Describe secondary active transport

Answer 12

Movement of molecules indirectly coupled with ATP hydrolysis

Question 13

Describe primary active transport

Answer 13

Movement of molecules that occurs at the SAME site of ATP hydrolysis

Question 15

What do transporters such as solute carriers and pumps generally move across cell membranes?

Answer 15

Solutes such as larger nutrients, waste, small molecules and pumping molecules

Question 16

If considering 3 molecules, glycerol, glucose, and sucrose are crossing the lipid bilayer, why can glycerol utilize simple passive diffusion while the others cannot?

Answer 16

Because glycerol is a SMALLER molecule. While they are all uncharged which allows them to cross the PM, the other two are too large to pass via simple passive diffusion

Question 17

Name the four types of ion channels

Answer 17

Ligand gated
Voltage gated
Leak
Stretch activated

Question 18

Describe ligand-gated ion channel

Answer 18

Uses a lock and key type method, binding of ligand opens the channel

Question 19

Describe a leak channel

Answer 19

Continuous flow of ions, still down the concentration gradient

Question 20

Describe voltage gated channel:

Answer 20

Change in voltage across the membrane changes the electric field such that the internal sensor allows for electrolyte movement

Question 21

Describe stretch activated channels

Answer 21

Actual size and shape of pore and gating modified by amount stretched

Question 22

Describe solute carriers as a form of facilitated passive transport

Answer 22

The carrier protein allows molecules to flow down the concentration gradient which can be bidirectional based on concentration inside and outside the cell

Question 23

What type of plasma membrane protein may engage in both passive facilitated transport and secondary active transport?

Answer 23

Solute carriers

Question 24

Describe a situation using solute carriers as a form of secondary active transport

Answer 24

This form of movement is coupled with a primary active transport. For example the transport of glucose
First the primary active transport Na+/K+ transporter moves sodium out of the cell. When the concentration of sodium is high outside the cell, it engages with the Na+/Glucose co-transporter to move glucose back into the cell

Question 25

Describe the movement of molecules using primary active transport of Na+/K+-ATPase

Answer 25

1.) 3 Na+ and 1 ATP bind to carrier protein
2.) Hydrolysis of ATP to ADP and phosphate as the protein conformation changes moving the Na+ outside of the cell
3.) New conformation binds 2 K+ ions from the outside of the cell
4.) 2 K+ ions move to the inside of the cell and the Phosphate is released inside the cell as well
5.) Conformation of pump reverts to original conformation

Question 26

Which lung has 2 lobes and why?

Answer 26

The L lung to allow space for the heart

Question 27

Describe the “Pump/Leak model” in cell concentration gradients

Answer 27

The pump and leak channels are working simultaneously but independently

Question 28

List the breakdown of body weight for following components:
Water
protein
Mineral
Fat

Answer 28

Water: 60%
Proteins: 18%
Mineral: 7%
Fat: 15%

Question 29

Of the total body water, how much is directed to the Extracellular fluid compared to the intracellular fluid

Answer 29

20% is ECF
40% is ICF

Question 30

About how much of total body weight is plasma volume?

Answer 30

4-5%

Question 31

Of the extracellular fluid, about how much is interstitial fluid and how much is plasma

Answer 31

3/4 is interstitial fluid
1/4 is plasma volume

Question 32

How many liters are in a kilogram

Answer 32

1 L = 1 kg

Question 33

Of total body weight, what percentage is water in the ECF and water in ICF

Answer 33

ECF is 20% of total body weight
ICF is 40% total body weight

Question 34

List 6 common major electrolytes

Answer 34

Na+, K+, Ca+, HCO‾₃, Impermeable anions, Cl-

Question 35

Outside the cell has larger amount of which major electrolytes?

Answer 35

Na+, Cl-, HCO‾₃

Question 36

Inside the cell, what major electrolytes are found in larger quantity compared to outside the cell

Answer 36

K+ and impermeable anions

Question 37

When considering the interstitial space compared to plasma in the ECF, explain the distribution of protein, K+ and Na_

Answer 37

Interstitium and plamsa both have low K+ and high Na+
Protein distribution is 1 g/dl in the interstitium and 7 g/dl in the plasma, so higher protein concentration in plasma

Question 38

When the concentration is meq/l what component does this represent?

Answer 38

Concentration of charged ions

Question 39

When the concentration if mmol/l, what component is this representing?

Answer 39

2 oppositely charged ions associating in solution

Question 40

When concentration is given as mg/100 ml (dl), what component is this representing?

Answer 40

uncharged solutes

Question 41

Concentration of charged ions are given as meq/l. When 2 oppositely charged ions associated in solution they form a molecule and the concentration is given in:

Answer 41

mmol/l

Question 42

Where is the highest concentration of proteins?
A.) intracellular
B.) ECF
C.) interstitial space
D.) plasma

Answer 42

A.) intracellular with 30 mg/dl

Question 43

Explain the electrochemical gradient

Answer 43

By inducing a concentration gradient you can induce an electrical gradient via ion movement
At equilibrium the concentration gradient is equal and opposite the electrical gradient

Question 44

Define Electrochemical Equilibrium Potential

Answer 44

The voltage (potential) that arises at equilibrium when electrical and chemical forces are equal and opposite

Question 45

When the mV is zero between the inside and outside of cell what does that mean?

Answer 45

Means there is now flow of ions from one side to another, no channels allowing passaged through the lipid bilayer to create electric gradient

Question 46

When measuring the cell membrane potiential of a cell, where does the majority of this come from and why?

Answer 46

Most determined by the K+ leak channel because it is an “excellent conductor in the resting cell membrane” that allows leakage of K+ out of the cell. while the Na+ channel is not a good conductor and the NA+/K+ Channel dictates very little, though the Na+/K+ATP-ase directs the large chemical gradients

Question 47

How does metabolic acidosis result in hyperkalemia?

Answer 47

1.) Drop in pH of plasma due to H+ ions moving into the cell due to concentration gradient (H+ protons higher concentration outside cell)
2.) Due to more protons coming in, there is exchange of H+ for 1 K+, silent exchange as the membrane potential is not effected
3.) So excessive K+ is being driven out of cell

Question 48

How can metabolic acidosis be corrected to diminish hyperkalemia

Answer 48

Injecting insulin will active Na+/K+ ATP-ase to drive more K+ into the cell

Question 49

How does Rhabdomyolysis cause cardiac cell electrical imbalance

Answer 49

1.) Skeletal muscle is crushed that contains lots of K+
2.) the crushing pushes K+ outside the cell into plasma
3.) Hyperkalemia causes influx of K+ INTO the cell due to the leak channels being bidirectional
4.) Makes the inside of cell LESS NEGATIVE, aprox -20 mV instead of -90 mV (depolarized)
5.) Less negative can cause cardiac arrhythmia

Question 50

Water soluble hormones would act on receptors found:

Answer 50

Cell surface

Question 51

Lipid soluble hormones would act on receptors found:

Answer 51

Intracellular

Question 52

The inside of a cell has the highest protein concentration. Outside of the cell, where is the higher concentration of protein? Interstitial space or plasma space?

Answer 52

Plasma, with 7 g/dl compared to the interstitium of 1 g/dl

Question 53

What is the barrier between the interstitial and plasma space?

Answer 53

Capillary wall

Question 54

What do we use to measure the volume of a specific body compartment?

Answer 54

Dilution principle

Question 55

Define the 4 basic parameters of the dilution principle:

Answer 55

1.) Exact quantity of known soluble substance
2.) Dissolve in H20 until evenly disperse
3.) Take same
4.) Volume= X/C AKA volume substance added/concentration of solution at equilibrium

Question 56

When using the dilution principle in vivo, what must be accounted for and how does it change the volume calculated?

Answer 56

Must correct for any of the solute that is removed from the body (aka excreted at equilibrium)
Volume=X-quantity excreted/C

Question 57

What is the equation to calculate an unknown volume?

Answer 57

V=g/(g/L) wherein dividing solute by concentration of solution at equilibrium

Question 58

When measuring and calculating unknown volume of plasma, what requirement of the solute must be met?

Answer 58

The solute must be retained in the plasma, not able to move back and forth freely. Like proteins and albumin can’t cross the capillary wall into the interstitial space
Use 131-iodine labeled albumin or EVANS but dye that binds to plasma proteins

Question 59

If measuring and calculating entire unknown extracellular fluid volume (interstitial/plasma) , what solute is used and why?

Answer 59

Use Inulin, a sugar foreign to body
Radiolabeled sodium or chloride
Because they move freely between interstitium and plasma space via capillary

Question 60

If measuring and calculating unknown total body water volume, what must the solute be able to do? What 2 solutes are normally used?

Answer 60

Must be able to travel freely in ECF and ICF just like water does
Either use Deuterium oxide (D2O) or Tritiated H2O (heavy/radioactive water)

Question 61

T/F: the unknown volume intracellular fluid volume can be measured directly

Answer 61

False, calculate the unknown volume
Total body water-ECF volume=ICF volume

Question 62

100 ml of Deuterium oxide in isotonic saline was injected intravenously into a normal, lean man weighing 84 kg. After 2 hours equilibration the concentration of D2O in plasma water was 0.2%. The body loss of D2O were averaged to be 4% of the total dose.
What is the total body water as absolute volume and expressed as a percentage of the body weight

Answer 62

1.) Amt added-Amt Lost/FINAL concentration
2.) 100 ml - 4% = 96 ml
3.) Final concentration: 0.2 D2O of total solution, 100 ml H20
0.2/100 ml=Final concentration
4.) 96 ml / (0.2/100 ml) =48000 ml or 48 L
5.) 48 L= 48 kg, 48/84, ~56% total BW

Question 63

The movement of water and small solutes across capillary wall is always ______________. It is determined by 2 pressures: 1.)
2.)

Answer 63

passive
1.) hydrostatic pressure: filtration
2.) oncotic pressure

Question 64

What is the basic concept of hydrostatic pressure

Answer 64

Fluid pressure of the blood that forces/pushes water and solute out of the capillary
Filtration

Question 65

What is the basic concept of osmotic pressure (oncotic pressure///0

Answer 65

Pressure exerted by proteins that pulls water inside the capillary, absorption

Question 66

At the beginning of a capillary, the ______________ pressure is greater than the ______________ pressure. So fluid movement is ____________ of the capillary

Answer 66

Hydrostatic
Osmotic/oncotic
Outside of the capillary, filtration

Question 67

At the end of the end of a capillary, the flow of blood requires a drop in ___________________ pressure so that _____________ is greater here. So fluid movement is ________________ of the capillary

Answer 67

Hydrostatic
Osmotic/oncotic
inside, absorption

Question 68

Why does the hydrostatic pressure fall when going from start of a capillary to end?

Answer 68

As the fluid moves out of the capillary, the concentration of plasma protein becomes higher because water was pulled out

Question 69

When speaking of volume changes, it is referencing the movement of _____________ cellular fluid

Answer 69

Extra

Question 70

Define osmolality

Answer 70

number of free (disassociated) particles in solution
or number of particles per kilogram of water

Question 71

What determines osmolality?

Answer 71

Solutes in the body

Question 72

What is/are the units of osmolarity?

Answer 72

Osm (oz-moles) or mili osm/Kg or L of H2O
1 MW (g) or a non-ionized solute

Question 73

The majority of ECF osmolality is determined by electrolytes (ions) which ___________ to produce a molecule and _____________ in solution

Answer 73

Associate
Dissociate

Question 74

T/F the total osmolality in the ECF and ICF are not equal because there are different amounts of solutes on either side

Answer 74

False, while there may be more than one type of solute in ECF or ICF, the total osmolality is about equal because water is allowed to move freely to balance

Question 75

What drives the movement of water in ECF between insterstitial space and plasma space?
What drive the movement of water between the cell wall, ICF to ECF?

Answer 75

1.) Hydrostatic pressure and oncotic pressure
2.) Osmotic gradients

Question 76

Water ALWAYS moves from areas of:

Answer 76

Low to high SOLUTE concentration

Question 77

Why would NaCl solution generate a movement of 0 sustained osmotic effect?

Answer 77

Because, without active transport, NaCl cannot cross the cell membrane
If NaCl is not moving, the water that maintains osmolality does not move, so water inside the cell does not change either to balance osmolality

Question 78

Describe the movement of glucose solution relative to osmotic movement.

Answer 78

The glucose enters the cell, which pulls in water
As the glucose is metabolized, the concentration of water inside the cell is higher and moves out of the cell because the intracellular osmolality is decreased, equivalent to infusing pure water

Question 79

Describe the movement of urea in solution and water movement across a cell

Answer 79

Urea is permeable, though not actively taken up by cells
Urea flows diffuses slowly the concentration gradient, from high (ECF) into low (ICF) which pulls H2O too
Since this is a slow process, the urea diffuses at the same rate as water so osmolality does not change but volume goes up inside the cell

Question 80

Why is hyperkalemia dangerous?

Answer 80

First, the inside of cell is negative due to constant outflow of K+ from the cell via concentration gradient
If there is too high K+ outside the cell, the membrane potential is disrupted and the cell becomes more positive
The cell becoming more positive is essentially inducing depolarization which allows action potential of muscle and nerve cells which causes spasm

Question 81

All movement across the capillary wall is ____________ and driven by:

Answer 81

Passive
Hydrostatic pressure and oncotic/osmotic pressure

Question 82

Hormones with receptors on cell SURFACE, elicit what type of response?

Answer 82

Rapid response/effects
i.e. enzyme phosphorylation, channel activation
AND/OR
Slow (genomic) signaling for gene transcription or translation

Question 83

Generally, hormones that bind INSIDE the cell (lipid soluble) will elicit what type of effect?

Answer 83

Slow (genomic) signaling

Question 84

T/F: Few lipid soluble hormones may elicit rapid signaling, i.e. steroids that bind to proteins on the membrane-fast signaling

Answer 84

T

Question 85

What is another name for cell surface receptors?

Answer 85

Plasma membrane

Question 86

What is another name(s) for intracellular receptors?

Answer 86

Cytosolic and nuclear receptors

Question 87

List the 3 major categories of cell surface receptors:

Answer 87

1.) G protein coupled receptors
2.) Ionotropic receptors
3.) Catalytic receptors

Question 88

List the 3 types of intracellular receptors

Answer 88

1.) Steroid hormone receptors
2.) Thyroid hormone receptors
3.) Vitamin D metabolite receptors

Question 89

What is another name for seven transmembrane domain receptors (7TM)

Answer 89

G protein coupled receptors

Question 90

What usually binds to cell surface receptors?

Answer 90

Proteins, enzymes, peptides, amino acids, small molecules i.e. amines

Question 91

On GPCR receptors, where is the N terminus located? Where is the C terminus located?

Answer 91

N terminus is extracellular
C terminus is intracellular

Question 92

What binds to 7TM receptors at 5,6 cytoplasmic loop?

Answer 92

This is where the G proteins bind, hence the name

Question 93

Why is the GPCR also names 7TM receptor?

Answer 93

It is become known the C terminus of this receptor can bind intracellular proteins to elicit intracellular effects such that a receptor site exists in the 7th region

Question 94

List 4 receptor categories comprising G protein coupled receptors

Answer 94

1.) Adrenergic receptors
2.) Muscarinic receptors
3.) Peptide/Glycoprotein receptors
4.) Calcium receptors

Question 95

What are 6 types of hormones that may bind to Peptide/Glycoprotein receptors

Answer 95

Vasopressin, PTH, angiotensin II, Somatostatin, TSH, FSH

Question 96

What are the 2 subtypes of Vasopressin receptors. What type of receptor are they on a less specific scale

Answer 96

1. V1 & V2 receptors
   2.) G protein coupled receptors which are plasma receptors

Question 97

List 4 subtypes of Adrenergic receptors

Answer 97

α1, α2, β1, β2

Question 98

Although each hormone has it’s own corresponding specific receptor, structural similarities may allow some receptors to bind other hormones. Such as
1.)
2.)

Answer 98

1.) Mineralocorticoid receptors may bind glucocorticoid hormones
2.) α-adrenergic receptors prefer to bind norepinephrine but can bind epinephrine and vice versa as β-adrenergic receptors prefer to bind Epinephrine will bind norepinephrine

Question 99

What is another name for ionotropic receptors and describe their mechanism of action

Answer 99

AKA Ligand-gated ion channel
Membrane spanning units wherein a ligand binds to extracellular component where the channel opens to allow cations into the cell

Question 100

Describe the ionotropic receptor, nicotinic acetylcholine receptor

Answer 100

1.) Acetylcholine is released from a nerve cell and acts on paracrine level
2.) ACH binds to nicotinic receptor on adrenal chromaffin cells
3.) Once ACH is bound to nicotinic receptors, Ca+2 is allowed to enter the cell which induces epinephrine secretion

Question 101

List the 5 classes of catalytic receptors

Answer 101

*1.) Receptor guanyl cyclase
2.) Receptor serine/threonine kinases
*3.) Receptor tyrosine kinases
*4.) Tyrosine kinase-associated receptors
5.) Receptor tyrosine phosphatases

Question 102

What type of cell membrane receptors may cause the extracellular domains to dimerize?

Answer 102

Catalytic receptors

Question 103

List the 3 steps of receptor guanylyl cyclase

Answer 103

1.) start with receptor that has 3 domains, one extracellular, one intracellular, one spanning membrane layer
2.) Ligand binds to extracellular domain
3.) 2 receptors dimerize
4.) Intracellular guanylyl cyclase domains are activated
5.) activated guanylyl cyclase converts GTP to cyclic CMP

Question 105

Give an example of a catalytic receptor, more specifically a receptor guanylyl cyclase

Answer 105

Atrial natriuretic peptide receptor, ANP

Question 106

Give 2 example of Catalytic receptors, more specifically receptor tyrosine kinases

Answer 106

1.) Nerve growth factor receptor
2.) Insulin receptors

Question 107

How does Nerve growth factor receptor work? What type of receptor is it?

Answer 107

1.) Nerve growth factor binds to its receptor and causes dimerization and activates the intrinsic tyrosine kinase. The tyrosine kinase directs tyrosine phosphorylation of cytosolic proteins
2.) it is a type of receptor tyrosine kinase and thus a catalytic receptor thus a type of Extracellular receptor

Question 108

Describe what happens when insulin binds to its catalytic receptor

Answer 108

1.) The receptor is a tetramer with 2 α & 2 β chains
2.) The insulin binds to the α chain.
3.) Conformational change to receptor, α & β interaction and activation of intrinsic tyrosine kinase
4.) The tyrosine kinase directs tyrosine phosphorylation of cytosolic proteins

Question 109

Give 2 examples of tyrosine kinase-associated receptors

Answer 109

1.) Growth hormone receptor
2.) Interleukin-6 receptor

Question 110

What makes tyrosine kinase-associated receptors different from other catalytic receptors?

Answer 110

The tyrosine kinase-associated receptors do not have an intrinsic internal kinase domain
Thus the tyrosine kinase is ASSOCIATED with the intracellular portion of the receptor

Question 111

Describe a tyrosine kinase associated receptor and what happens when a ligand binds

Answer 111

• Single molecule with extracellular, trans-membrane, and intracellular component WITH slightly different forms (α & β)
  1.) Ligand binding to extracellular domain will lead to formation of Homodimers, heterodimers, or heterotetramers which activates the receptor unit
  2.) The activated receptor can associate with a cytosolic tyrosine kinase with can phosphorylate various cytosolic proteins

Question 112

Describe the basic action of intracellular receptors

Answer 112

1.) Hormone binding to receptor converts the receptor into a transcription factor
2.) This associates with specific parts of the DNA called hormone response elements
3.) Eliciting gene transcription, either increase or repression

Question 113

List 3 examples of ligands that bind to intracellular receptors

Answer 113

1.) steroid hormones
2.) Thyroid hormone
3.) Vitamin D hormone

Question 114

What is an important feature of intracellular receptors that occurs with DNA binding

Answer 114

The receptors bind to DNA 7as homodimers or heterodimers
OR bind with RxR

Question 115

Where are mineralocorticoid and glucocorticoid receptors found?

Answer 115

Intracellular, more specifically cytoplasmicQ

Question 116

Where are Estrogen and progesterone receptors found?

Answer 116

Intracellular, nuclear

Question 117

Where are thyroid receptors found?

Answer 117

Intracellular, bound to DNA in the nucleus

Question 118

What is T3?

Answer 118

Thyroid hormone

Question 119

Where is the thyroid hormone receptors in the unbound state?

Answer 119

The thyroid hormone receptor is bound to DNA and thus acting as a repressor

Question 120

Describe Glucocorticoid receptor in the resting/unbound state. What happens when cortisol enters and binds to the glucocorticoid receptor

Answer 120

In resting state, GR is bound to heat shock protein (hsp 90) in the cytosol
1.) Cortisol enters cell and binds to GR and HSP90 disassociates
2.) Gr+Cortisol complex enters nucleus, binds to DNA and turns on transcription

Question 121

What does parathyroid hormone do?

Answer 121

acts in kidney and bone to increase blood Ca+2 levels

Question 122

What occurs in pseudohypoparathyroidism?
What type of receptor is in action?

Answer 122

The Gαs protein that the PTH receptors normally signals is defective. Thus, hypocalcemia occurs since PTH usually increases Ca+2 levels
Cell membrane receptor, GPCR

Question 123

In nephrogenic diabetes, what is occurring?
What type of receptor is acting?

Answer 123

ADH cannot bind to V2 receptors in the collecting duct and water is not reabsorbed
Cell membrane receptors, G protein coupled receptor

Question 124

One type

Question 125

Describe one cause of hypothyroidism on a receptor level
What type of receptor is involved

Answer 125

Autoantibodies inhibit TSH receptors on thyroid cells.
The TSH cannot stimulate thyroid hormone production and secretion by the thyroid gland, so there are low blood levels of thyroid hormone
G protein coupled receptors

Question 126

What are the 2 main cell types of the CNS?

Answer 126

Neurons & Glial cells

Question 127

How do neurons communicate?

Answer 127

Via action potential and neurotransmitter release

Question 128

What is a tract or pathway in the CNS?

Answer 128

Groups of axons traveling together in the CNS

Question 129

What are the neuronal cell bodies called in the PNS?

Answer 129

Ganglia

Question 130

T/F: In the PNS, glia and neurons are both present within the ganglia

Answer 130

True

Question 131

Define: Afferent

Answer 131

Sensory information
Carries information TOWARDS the CNS

Question 132

Define direction of Efferent neurons:

Answer 132

Neurons carry information from CNS to PNS
From motor & autonomic system

Question 134

Efferent neurons control:

Answer 134

Skeletal, cardiac, smooth muscle and organs and glands

Question 135

What is the somatic nervous system?

Answer 135

1/2 parts of the functional nervous system component
Receives sensory information from skeletal muscle and controls skeletal muscles of the body
And monitoring external environment, including taste and pain

Question 136

What is the autonomic nervous system

Answer 136

1/2 parts of functional nervous system
Receives sensory information from glands, vasculature, and internal organs as well as controls these
Regulates breathing, BP, feeding, elimination etc

Question 137

T/F: The Autonomic system is controlled by the CNS while the somatic nervous system is controlled by the PNS

Answer 137

False, both the autonomic and somatic nervous system have CNS and PNS components

Question 138

Name the 5 components of the CNS (6th would be the spinal cord)

Answer 138

All in the brain
1.) Medulla oblongata
2.) Pons
3.) Cerebellum
4.) Midbrain
5.) Diencephalon
7.) Cerebral hemispheres

Question 139

What is does the medulla oblongata do?

Answer 139

Autonomic function
I.e. breathing, blood pressure, digestion

Question 140

Where do the afferent neurons synapse?

Answer 140

In the nucleus of the solitary tract which is in the Medulla oblongata

Question 141

What does the Pons do?

Answer 141

Important in movement
Exchanges information between cerebellum and and cerebral hemispheres
Urinary functioning

Question 142

What does the cerebellum do?

Answer 142

Coordination of movement
Control of posture and balance

Question 143

What does the midbrain do?

Answer 143

Sensory and motor functions, eye movement, coordination of hearing and vision

Question 144

What 3 components comprise the brain stem?

Answer 144

Medulla, pons, midbrain

Question 145

What does the thalamus do?

Answer 145

processing information from the brain/CNS to the cerebral hemispheres

Question 146

What is the diencephalon comprised of?

Answer 146

Thalamus
Hypothalamus

Question 147

What does the hypothalamus do?

Answer 147

Regulate endocrine, autonomic and visceral function

Question 148

What is another name for the subcortical nuclei? Where are they located?

Answer 148

Basal ganglia
In cerebral hemispheres

Question 149

What do the basal ganglia do?

Answer 149

Control movement, posture, complex behavior

Question 150

Patients diagnosed with Parkinson’s disease have dysregulation of:

Answer 150

Basal ganglia

Question 151

What does the cerebral cortex do?

Answer 151

Skilled movement, learning, reasoning, memory
Some influence of autonomic function

Question 152

The peripheral nervous system consists of ____________ (bundles of axons) and ganglia ( groups of _______________ ___________ _________ and____________)

Answer 152

nerves
Neuronal cell bodies
Glia

Question 153

Sensory nerves are synonymous to:

Answer 153

Afferent

Question 154

Motor nerves are synonymous to:

Answer 154

Efferent

Question 155

List the 3 divisions of the autonomic nervous system

Answer 155

Sympathetic
Parasympathetic
Enteric

Question 156

Describe the difference between the sympathetic and parasympathetic divisions in regard to organ system control

Answer 156

Sympathetic: diffuse control
Parasympathetic: fine control over individual organ system

Question 157

T/F: since the enteric system is considered “the brain of the gut” it is solely under enteric control

Answer 157

False, it may be influenced by parasympathetic and sympathetic nervous control but mainly relies on enteric

Question 158

The ______________ nervous system innervates most visceral organs of the body

Answer 158

Sympathetic

Question 159

Describe the composition of ganglion of the sympathetic nervous system

Answer 159

Cell bodies start in Thoracic or lumbar spine with post ganglion near the spinal cord
Thus in sympathetic nervous system, the preganglia are short and post ganglia are long

Question 160

Why is it true that sympathetic nerve activity to multiple tissues can be increased simultaneously?

Answer 160

Because sympathetic nervous system has diffuse control over nervous system

Question 161

Where do cell bodies of parasympathetic nervous system originate?

Answer 161

Brain and spinal cord

Question 162

Describe the composition of ganglia in the parasympathetic nervous system

Answer 162

Preganglia are very long and project to the target organ
Cell bodies of the post ganglia are adjacent to or within the target organ
Preganglia are long and post ganglia very short

Question 163

How does having post ganglia adjacent or within target organ affect parasympathetic control?

Answer 163

Allows for each tissue to be under separate control

Question 164

T/F: Most organs, glands and smooth muscle are under dual control of sympathetic and parasympathetic nervous system

Answer 164

True

Question 165

Describe a situation wherein the parasympathetic and sympathetic nervous system act in union rather than antagonisitcally

Answer 165

Male sexual function
Parasympathetic acts for erection
Sympathetic nervous system acts in ejaculation

Question 166

Very little ______________________ innervation exists in blood vessels. Decreases in blood pressure are mediated by ____________________ withdrawl

Answer 166

Parasympathetic
Sympathetic

Question 167

Primary control of blood pressure by the autonomic nervous system is by:

Answer 167

Increases and decreases of sympathetic nervous system

Question 168

What are the predominant neurotransmitters that are released by the postganglions of the sympathetic nervous system

Answer 168

Norepinephrine, to a lesser extent epinephrine
Some but very little release of acetylcholine

Question 169

What is the predominant neurotransmitter released by preganglion to cell body in parasympathetic nervous system? What is the predominant neurotransmitter released by postganglion to effector organ in parasympathetic nervous system?

Answer 169

Pre: Acetylcholine
Post: Acetylcholine

Question 170

What is the predominant neurotransmitter released by preganglion to cell body in sympathetic nervous system? What is the predominant neurotransmitter released by postganglion to effector organ in sympathetic nervous system?

Answer 170

Pre: acetylcholine
Post: norepinephrine and epinephrine

Question 171

What is the special case in the sympathetic nervous system regarding adrenal medulla?

Answer 171

The preganglion releases Acetylcholine to the cell body inside the adrenal medulla. But there is no post ganglion. Rather the adrenal medulla directly releases epinephrine or norepinephrine into the bloodstream where it can travel and exert effects

Question 172

Acetylcholine is released by ALL preganglions in __________________ and ________________________ nervous system. The receptors for Ach are:

Answer 172

Parasympathetic and sympathetic
Nicotinic receptors on post ganglia

Question 173

In the _________________________ system, the postganglionic neurons release ACETYLCHOLINE on __________________ receptors of the target organ

Answer 173

Parasympathetic
Muscarinic receptors

Question 174

In the ____________________ postganglionic neurons usually release NOREPINEPHRINE which acts on either ____or _____ _______________ ___________

Answer 174

Sympathetic
α or β adrenergic

Question 175

Where is the exception to sympathetic postganglionic neurons release acetylcholine to action on muscarinic receptors?

Answer 175

In sweat glands

Question 176

T/F: The somatic nervous system has pre and post ganlion

Answer 176

False, the voluntary motor nerve leaves spinal cord and acts on effector organ with Ach release on nicotinic receptors

Question 177

Acetylcholine either acts on ___________________ or ___________________ receptors while norepinephrine/epinephrine act ion ______________________ receptors

Answer 177

Nicotinic or Muscarinic

β or α Adrenergic receptors

Question 178

List the subtypes of α Adrenergic receptors
List the subtypes of β adrenergic receptors

Answer 178

1a.) α ₁
2a.) α ₂

1b.) β ₁
2b.) β ₂
3b.) β ₃

Question 179

______ receptors are responsible for the contractile effects of norepinephrine/epinephrine (blood vessels, urogenital, sphincters)

Answer 179

α ₁

Question 180

____ receptors are responsible for the stimulatory effects of norepinephrine/epinephrine in heart

Answer 180

β ₁
Can increase HR and contractility

Question 181

____ receptors are responsible for relaxing effects of GI tract, urogenital system, airway, some blood vessels

Answer 181

β ₂

Question 182

What systems control bladder function?

Answer 182

Parasympathetic, sympathetic, somatic system

Question 183

______________ stimulation causes contraction of the bladder wall (detrusor muscle) and relaxation of the relaxation of the internal sphincter

Answer 183

Parasympathetic

Question 184

Which division of the autonomic nervous system allows urination?

Answer 184

Parasympathetic because it contracts the bladder wall and relaxes the internal sphincter

Question 185

______________________ stimulation promotes relaxation of the bladder wall and causes contraction of the internal sphincter to inhibit urinationTh

Answer 185

Sympathetic

Question 186

Why does referred pain occur?

Answer 186

Because visceral tissue and somatic tissues send afferent pain information to synapse on same neurons in spinal cord, when info reaches the brain it cannot determine where the signal originated due to convergence at the spinal cord

Question 187

Define TRANSGENIC MOUSE

Answer 187

DNA is randomly inserted into the genome by injecting the male pronucleus shortly after fertilization

Question 188

Define Knock-in (Knock-out) mouse

Answer 188

Changes introduced into a endogenous gene via homologous recombination with manipulated DNA from the gene

Question 189

Define homologous recombination

Answer 189

A type of genetic recombination in which nucleotide sequences are exchanged between two similar or identical molecules of DNA

Question 190

Why are mice used to model human physiology?

Answer 190

95% of mouse genome is similar to humans
Small and short generation time
Accelerated lifespan, 1 mouse year ~30 human years
Ability to directly manipulate mouse genome

Question 191

What type of genetic manipulation yields a chimeric mouse?

Answer 191

Targeted gene manipulation

Question 192

Knock-in and Knock-out gene manipulation is also known as ______________________ _____________

Answer 192

Targeted manipulation

Question 193

How does transgenesis work?

Answer 193

1.) Collect fertilized egg
2.) Take a gene promotor and gene of interest. Inject DNA into male pronucleus of the fertilized egg
3.) Implant injected embryo into pseudopregnant female who will yield transgenic offspring

Question 194

Why do transgenic mice have some off target effects?

Answer 194

Because the uptake of DNA is random in location and number to transgenes copies so expression of gene is not predictable

Question 195

What is homologous recombination

Answer 195

Nucleotide sequences are exchanged between two similar or identical molecules of DNA

Question 196

List the basic steps of Gene targeting

Answer 196

1.) Targeting vector
2.) Gene targeted to embryonic stem cells through homologous recombination
3.) Targeted cells are selected, expanded, and cryopreserved
4.) Determine if gene was inserted in correct location via PCR sequencing or Southern Blot
5.) Targeted embryonic stem cell injected into early mouse embryo
6.) Chimera offspring
7.) Breeding of chimera

Question 197

What does CRISPR stand for?

Answer 197

Clustered Regularly-Interspaced Short Palindromic Repeats

Question 198

What is the basis of CRISPR/Cas9 System

Answer 198

Made double strand DNA breaks at precise locations to allow to silence gene or edit in a particular region of DNA

Question 199

What are clustered regularly-interspaced palindromic repeats?

Answer 199

w/in bacteria genome there are a sequence of repeats that are divided by viral genomes

Question 200

T/F: Hypothalamus can directly control preganglionic sympathetic neurons

Answer 200

True

Question 201

All movement across the ________________ ____________ is passive, driven by __________ and _________________ pressures.

Answer 201

capillary wall
hydrostatic and colloid (oncotic) osmotic

Question 202

What would be seen in expression of reporter genes

Answer 202

It allows the visualization of a gene at a specific site with fluorescent dye

Question 203

What is a major drawback to the genetic manipulation of knock in or knock out mice? What is the solution to this problem?

Answer 203

The gene is then turned off or on for the rest of the germ line, all offspring will be knock in or knock out
To circumvent, use conditional gene manipulation

Question 204

What does Cre recombinase do?

Answer 204

Catalyzes site specific recombination of DNA between two loxP sites

Question 205

What is target of Cre recombinase?

Answer 205

The 34 bp sequence LoxP site

Question 206

Describe the organization of a loxP site

Answer 206

Inverted repeat, 8 bp spacer, inverted repeat

Question 207

What are 3 conditions ideal for control mice in Cre/Lox system? Why are the controls important

Answer 207

Mice contain neither loxP allele or Cre
Miice express only Cre-recombinase
Mice expressing only the loxp-flanked gene
- We don’t know exactly how the loxP or Cre are impacting physiology, do they impact together or separately?

Question 208

When Cre is “turned on” whenever the promotor of interest is “turned on”, leading to deletion of interest early in development. Sometimes the gene being deleted is vital for development. What is one system to circumvent this problem?

Answer 208

Inducible conditional gene targeting, Tamoxifen or Treatracycline-inducible
This uses Cre to remove component that blocks entry into the nucleus

Question 209

When Cre is “turned on” whenever the promotor of interest is “turned on”, leading to deletion of interest early in development. Sometimes the gene being deleted is vital for development. What a second system to circumvent this problem?

Answer 209

Using virally-mediated gene transfer of cre-recombinase
Using the virus to direct Cre to the area of interest

Question 210

What is the major difference between transgenic and gene targeting?

Answer 210

Transgenic sends a transgene to a random part of the genome
Gene targeting using homologous recombination to target a gene to a specific area in the genome

Question 211

The body secretes about ______ L of intestinal juices daily. But only ____ mL is secreted by feces. This means:

Answer 211

8 L
100 mL
Most of intestinal juices are reabsorbed

Question 212

What is the flow of filtered waste from the glomerulus to the ureter:

Answer 212

Bowman’s capsule to PCT to loop of Henle to DCT to collecting duct to ureter

Question 213

T/F: the membrane relative permeability to K+ is high

Answer 213

True

Question 214

What ion is primarily responsible for establishing a cell membrane potential?

Answer 214

K+

Question 215

What facilitates the disassociation of GDP from alpha subunit on GPCR?

Answer 215

GEF facilitates exchange of GDP to GTP so alpha subunit can disassociate from beta and gamma subunits and interact with the effector

Question 216

What modulate Adenyl Cyclase in CPCR?

Answer 216

G alpha s and G alpha I

Question 217

Explain an example G alpha s acting as a stimulator for adenyl cyclase

Answer 217

G alpha s binds to adenyl cyclase to activate exchange of ATP for cAMP to activate PKA

Question 218

Explain an example G alpha I acting as an inhibitor for adenyl cyclase

Answer 218

G alpha i does not allow exchange of ATP for cAMP which disallows activation of PKA

Question 219

G alpha s subunits of GPCR proteins may stimulate adenyl cyclase via:

Answer 219

Vasopressin V2-receptor binding which ultimately allows for activation of PKA

Question 220

G alpha i subunits of GPCR proteins may inhibit adenyl cyclase via:

Answer 220

Epinephrine binding to alpha-2- adrenergic receptors which prevents exchange of adenyl cyclase-alpha complex exchanging ATP for cAMP

Question 221

Explain how G alpha Q units of GPCR units activate phospholipase C

Answer 221

G alpha Q binds to phospholipase C that allows PIP2 to activate DAG or increase insP3

Question 222

What does DAG do?

Answer 222

Activates enzyme protein kinase

Question 223

What does InsP3 do?

Answer 223

Signals release of Ca from the ER