Quiz 10 Flashcards by Ryan Davis

Name the essential amino acids

Histidine 
Isoleucine 
Leucine 
Lysine 
Methionine 
Phenylalanine 
Threonine 
Tyrosine 
Valine

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What are the four fates of dietary amino acids?

Protein synthesis
Energy production (citric acid cycle)
Biosynthesis
Urea excretion

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Name the three drivers for protein oxidation

Protein rich diet

Normal synthesis and degradation

Diabetes

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Dietary protein in the stomach leads to the release of what hormone?

Gastrin

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What polypeptide bonds does pepsin hydrolyze?

Phe
Trp
Tyr

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What does secretin do?

Stimulates the release of bicarbonate from the pancreas

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What does cholecystokinin do?

Stimulates zymogen release from the pancreas and causes gall bladder contractions

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What is the active form of the zymogen procarboxypeptidase a and b?

Carboxypeptidase a and b

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Where does most catabolism of amino acids occur? What is the main strategy?

In the liver. Cleaves off the amine group and recycles the carbons

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Name four amine group carriers

Glutamate
Glutamine
Alanine
Aspartate

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The carbons fro amino acids will be turned into ____ once the amino group is removed. Then, what is it converted to?

Alpha keto acids (alpha ketogluterate)

Will then be turned into pyruvate

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Amine groups are toxic in the body. How are they stabilized?

Converted to urea or Uric acid for excretion

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How is ammonia toxic?

It disrupts sodium potassium ATPase on astrocytes to prevent their K uptake. This will get rid of the concentration gradient so GABA cant work to inhibit signals. Leads to seizures, loss of consciences and death

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What are the two common amino acid catabolism reactions?

Transaminase reactions

One carbon transfers

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In a transaminase reaction, the amine group from an amino acid will be put on _____ to make it _____. The amino acid is thus converted to a _____.

Alpha ketogluterate

Glutamate

Alpha keto acid

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What enzyme aids in transaminase reactions?

Amino-transferases. They are specific to each amino acid transfer

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What is a common coenzyme for amino-transferases?

PLP (pyridoxal phosphate)

This is also better known as vitamin B6

It is the carrier of amino groups and help stabilize the amino groups in the transfer

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What carriers the amino groups through the blood to the liver?

Glutamine and glutamate

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Intracellular ammonia is buffered by converting ____ to _____

Glutamate to glutamine

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What enzyme is necessary for converting glutamate into glutamine?

Glutamine synthetase

It is an ATP dependent enzyme and adds another amino group to the molecule to make it glutamine

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True or false… almost all cells in the body have glutamine synthetase

True

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Other than amine groups getting to the liver by glutamine, what is another way it gets to the liver?

Glucose alanine cycle

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Describe the glucose alanine cycle

Amino groups from amino acids are transferred to make glutamate. Glutamate transfers the amino group to pyruvate to form alanine. Alanine is transported throughout the blood and to the liver where it is converted back to pyruvate to undergo gluconeogenesis

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True or false… the glucose alanine cycle occurs in aerobic states

False… it occurs in anaerobic states and coincides with the cori cycle

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What amino acid is absolutly essential for the urea cycle to work?

Ornithine

The urea cycle involves enzymes from within what organelle?

Mitochondria

In the urea cycle, what enzyme takes the amine group off of glutamine to form a free ammonium and glutamate?

Glutaminase

The amine group on glutamate in the urea cycle is removed by what enzyme? Once the amine group is removed, the molecule is called ____ and will enter the _____ ____ _____

Glutamate dehydrogenase Alpha keto gluterate Citric acid cycle

The free ammoniums in the mitochondria of the urea cycle will be added to _____ (which involves ___ _____) to form ______. What enzyme facilitates this reaction?

Bicarbonate 2 ATP Carbamoyl phosphate Carbamoyl phosphate synthetase 1 carries this out

Alanine loses its amine group to become _____. The amine group is transferred to ______, which then becomes ______.

Pyruvate Alpha ketogluterate Glutamate

The amine group from carbamoyl phosphate is transferred to _____ to become ______

Ornithine Citrulline

In the last step of the urea cycle, arginine is converted to _____ and forms _____ in the process

Ornithine Urea

In the urea cycle, citruline + aspartate form ______

Argininosuccinate

Argininosuccinate is converted to _____ and releases _____ in the process

Arginine Fumerate

How many amine groups are on urea. Where do they come from?

Two amine groups One from citrulline and one from aspartate... basically

75% of urea is moved to the ____ while 25% is moved to the_____

Kidneys to be excreted as urine Gall bladder to be released as bile

Carbamoyl phosphate synthetase 1 is allosterically regulated by ____

ATP. More ATP = more urea

some other things that upregulate the urea cycle are increased synthesis of....

Ornithine transcarbomoylase Arinosuccinate synthetase Arginosuccinase Arginase

How are the citric acid cycle and the urea cycle linked?

Argininosuccinate It releases fumerate which is part of the citric acid cycle (Aspartate-argininosuccinate shunt of citric acid cycle)

What is the difference between glucogenic and ketogenic?

Glucogenic = amino acids that can be converted to glucose Ketogenic - amino acids that can be converted to ketone bodies

Amino acid catabolism produces enzyme substrates that fuel __ to ___ % of cellular energy production

10-15%

What are the nonessential amino acids?

``` Alanine Asparagine Aspartate Glutamate Serine ```

Aspartate and asparagine can give rise to _____

Oxaloacetate

Alanine, cysteine, glycine, serine, threonine, tryptophan, can give rise to ____ which in turn can give rise to ____

Pyruvate Oxaloacetate

Isoleucine, leucine, threonine, tryptophan, can all give rise to _____

Acetyl coA

Leucine, lysine, phenylalanine, tryptophan, and tyrosine can all give rise to _____

Acetoacetyl-coA

Glutamate can give rise to _____

Alpha ketogluterate

Arginine, glutamine, histidine, and proline can all give rise to _____ which can in turn give rise to _____

Glutamate Alpha ketogluterate

Isoleucine, methionine, threonine, and valine can all give rise to _____

Succinyl coA

Phenylalanine and tyrosine can all give rise to ____

Fumerate

Name three important one-carbon transfer reaction cofactors

S-adenosylmethionine Biotin Tetrahydrofolate (These are one carbon group donors, often methyl groups, vitamins)

There is some overlap in what amino acids can be converted into. For example tyrosine can be converted to ____ or _____

Fumerate or acetyl coA

What amino acid is also a neurotransmitter?

Glutamate

The two amino acids ____ and ____ that feed into oxaloacetate, dont result in much energy because it enters late in the citric acid cycle

Asparagine and aspartate

What amino acids give rise to Pyruvate?

``` Serine Alanine Glycine Threonine Tryptophan Cysteine ```

What amino acids give rise to acetyl coA?

``` Tyrosine Leucine Isoleucine Lysine Threonine Phenylalanine Tryptophan ```

What amino acids give rise to alpha keto gluterate?

``` Glutamate Glutamine Proline Arginine Histidine ```

What amino acids give rise to succinyl coA?

Isoleucine Methionine Valine Threonine

What two amino acids give rise to oxaloacetate?

Asparagine | Aspartate

What are the borders of the infratemporal fossa?

``` Zygomatic arch Maxilla Mastoid process/TMJ Lateral pterygoid plate Temporal sphenoid bones Pterygomaxillary fissure ```

What nerve goes through foramen ovale?

What goes through the spinosum foramen? Nerve and vessel

Meningeal branch of the mandibular nerve Middle meningeal artery and vein

What is the fissure that separates the infratemporal fossa and the pterygopalatine fossa?

Pterygomaxillary fissure

What is the structure that separates the pterygopalatine fossa and the nasal cavity?

Sphenopalatine foramen

What nerve goes through the petrotympanic fissure?

Chorda tympani nerve

The temporomandibular joint is located in what fossa?

Mandibular fossa of the temporal bone

What makes up the posterior border of the Infratemporal fossa?

TMJ

True or false, the temporalis posterior fibers assist in retraction of the mandible

True

during depression of the mandible, contraction of what muscle pulls both the consular head and articular disc anterioinferiorly?

Lateral pterygoid muscle

What are the four muscles of mastication?

Temporalis Masseter Medial pterygoid Lateral pterygoid

The muscles of mastication are innervated by ____

What portions of the maxillary artery are within the infratemporal fossa?

First and second portions.. give or take

What veins are seen in the infratemporal fossa?

Pterygoid plexus

Blood flows out of the ITF into the ____ and ____ veins and can go via ____ and _____ ____

Facial Maxillary Ophthalmic Cavernous sinus

What are the boundaries of the pterygopalatine fossa?

``` Maxilla Pterygoid plate Pterygomaxillary fissure Sphenopalatine foramen Orbit ```

What structures are located within the pterygopalatine fossa?

``` Maxillary artery (3rd part) Maxillary nerve (V2) Pterygopalatine ganglion ```

What portion of the maxillary artery branches and runs anteriorly? What structure does it run through?

Infraorbital artery | Runs through the inferior orbital fissure

What artery branches off of the maxillary artery in the pterygopalatine fossa to run medically? What structure does it run through?

Sphenopalatine artery Runs through the sphenopalatine foramen

V2 runs into the pterygopalatine fossa via ____ _____

Foramen rotundum

Why dont synapses occur in the trigeminal ganglion?

These are all sensory, no synapses because they are pseudounipolar neurons

The greater and lesser palatine nerves exit the pterygopalatine fossa through the _____

Greater palatine canal (inferior)

True or false.. you can see the posterior superior alveolar nerve in the pterygopalatine fossa

True.. the others you cannot however because they branch off later

You can see the zygomatic nerve in the pterygopalatine fossa. This nerve will then split into what two nerves?

Zygomaticotemporal Zygomaticofacial

The infraorbital nerve will give rise to what two nerves?

Middle superior alveolar nerve Anterior superior alveolar nerve

Vidian's nerve is made up of what two nerves?

Greater petrosal and deep petrosal

What types of neurons are in the deep petrosal nerve?

Sympathetics

What cranial nerve is the greater petrosal nerve from?

Facial (7)

Vidian's nerve goes through what canal to enter the pterygopalatine fossa?

Vidian's canal (pterygoid canal)

Where would you find the palatovaginal canal?

In between the vomer and pterygoid

What two things run through the palatovaginal canal?

Pharyngeal branch of the maxillary nerve and the pharyngeal artery (ascending pharyngeal)

Name all of the branches of V2 that are from the pterygopalatine fossa

``` Zygomatic Nasopalatine Posterior superior alveolar Greater/lesser palatine Pharyngeal ```

Name the four parasympathetic ganglia in the head

Ciliary Pterygopalatine Optic Submandibular

What branch of trigeminal gives rise to the ciliary ganglion? What about submandibular? What about otic?

Ciliary - opthalmic Submandibular - mandibular Otic - mandibular

how does the pharyngeal nerve enter the pterygopalatine fossa ?

Palatovaginal canal

____ provides carbon backbone for amino acid synthesis

Glucose

DNA is primarily in the _____ form

Nucleosome Not chromosomes!!! Thats for division

Which, introns or exons are spliced out?

Introns. "Exons are expressed"

Roughly what percent of mammalian DNA codes for proteins?

1.5%

Approximately how many genes do humans have?

25,000

What are the two components of the regulatory region of DNA?

Enhancer/silencer - binding of proteins that promote or inhibit transcription Promoter region - transcription factor and RNA polymerase binding

Describe the UTR

Untranslated region located at the 5' and 3' end of the open reading frame necessary for RNA processing

What do each of the following synthesize? RNA pol. 1 RNA pol. 2 RNA pol. 3

RNA pol. 1 - rRNA RNA pol. 2 - mRNA RNA pol. 3 - tRNA

DNA is read in what direction? What direction is RNA synthesized as?

Read 3' - 5' | Synthesized as 5' to 3'

Negative regulation of transcription involves ____ whereas positive regulation of transcription involves. _____

Represses Activators

What are the three RNA processing steps? List them in chronological order

Addition of a 5' cap Intron splicing Adding of a 3' poly A tail

What are the three functions of the 5' cap?

Protects mRNA in the cytoplasm Bound by ribosomes to initiate translation Cap-binding complex tethers the mRNA until transcription is complete

Where does a ribosome bind to mRNA

On the 5' cap

There are four classes of introns. Describe these classes

Two are self spliced | The other two involve splicesomes (most common)

True or false.... splicing variance creates different mRNAs and products

True true true

The AAUAAA is the upstream signal for _____.

Cleavage It sits about 20-15 nucleotides before actal cleaveage occurs

The actual cleavage site (where RNA pol. Is removed from the DNA) is rich in what two nucleotides?

G and U

What enzyme adds the poly A tail to the end of the mRNA

Polyadenylate

What functions does the poly A tail serve?

Protects mRNA tail in cytoplasm Anchors mRNA during translation

True or false... in order for mRNa to be exported into the cytoplasm via nuclear pore complexes, proteins must be bound to the mRNA

True

What is the first step of translation?

Activation of amino acids (charging the tRNAs with amino acids)

Which ribosomal subunit binds to the mRNA first the small or large?

Small subunit

True or false... ATP/GTP is not needed for the inition phase of translation

False!

In translation, the mRNA is read in what direction? Which end of the polypeptide is produced first N or C?

5' to 3' N to C

True or false, in elongation, making the bond for new amino acids requires GTP/ATP

False

True or false... the stop codon codes for a final amino acid

False.. instead, eukaryotic releasing factor is put in and causes everything to disintegrate

What is the role of the signal recognition particle?

It is like a flag that tells the protein where to complete translateion

Where are the two locations where translation may occur?

ER | Cytoplasmic space

Proteins that are produced in the ER will be what kind of proteins?

Integral membrane proteins Intravesicular proteins Secreted proteins

Where do most post-translational modifications occur? What are some of these post-translational modifications?

In the ER. Protein folding Proteolytic cleavage ``` Glycosylation Acetylation Phosphorylation Methylation Acyl action ```

Where is a likely site where glycoproteins are formed?

In the ER

What kind of proteins are produced from those translated in the cytoplasmic space?

Nuclear proteins Structurally associated proteins (like tubulin) Membrane associated proteins

What post-translational modification signals the protein for destruction?

Ubiquitin

What are the two primary organelles responsible for molecular degradation?

Proteosomes and lysosomes

Proteosomes degrade ___ while lysosomes degrade ____

Cytoplasmic proteins Vesicular and membrane proteins

True or false... in order for translation to occur, the 5' and 3' ends must be bound

True

The majority of fluid in the body is ______

Inside cells

How many liters = total body fluid? how many in blood? how many in plasma? how many in RBCs?

42 5 3 2

In general, waste products are ____ filtered and _____ reabsorbed

highly Poorly

True or false... the kidneys can deal with nonvolatile acids

True

Kidneys regulate pH by regulating their secretion/reabsorption of what?

HCO3. Although they can also deal with H+, HCO3 is more important

If the blood was too alkaline, what would the kidneys do?

Retain H+ and get rid of HCO3

The kidneys also can increase HCO3 by metabolising glutamine. What other product results form this?

NH4

What are some other renal functions? 3

Production of erythropoietin (increase RBCs) Gluconeogenesis Adrenal glands

Nephrons are located in the ____ ____ wich is located within the ____ of the kidney

Renal pyramids Medulla

Where does filtration occur?

In the glomerular capillaries into the nephron. This whole structure is called bowmans capsule

The efferent arterioles will give rise to the ___ ____ in which ____ and _____ occurs

Peritubular capillaries Reabsorption and secretion

Plasma containing salutes passes out of the glomerulus into the nephron and enters the ____ ______, then passes through the _____, then the _____ _____, then finally the ______. This is deposited into the ____ ____ and then _____

``` Proximal tubule Loop of henlie Distal tubule Collecting duct Renal pelvis Ureter ```

What are the only portions of the nephron that can be regulated?

Distal tubule and collecting duct

Which runs deeper into the medulla, the cortical or juxtamedullary nephrons?

Juxtamedullary

Which are more abundant, cortical or juxtamedullary nephrons?

Corical (70%) | Juxtamedullary (30%)

In the juxtamedullary nephron, the ______ extend part of the way down the loop of henlie and form specialized peritubular capillaries called the ______

Efferent arterioles Vasa recta

Around what percent of the blood plasma presented to the glomerulus enters the proximal tubule via bowman's capsule?

20%

True or false... the filtration rate is equal to rate of urine formation

False

What is the urinary excretion rate formula?

Filtration rate - reabsorbtion + secretion

A normal GFR is about how many liters per day?

180

The membranes of the glomerular capillaries is slightly specialized. It is selective and only will allow what things to pass through

Small and/or positively charged molecules

What are the three layers of the glomerular capillary membrane (have one extra)

Endothelium (fenestrated, negatively charged) Basement membrane (collagen/proteoglycan mesh, negatively charged) Podocytes (specialized epithelial cells)

What is the effect of the negatively charged endothelium and basement membrane?

Repelled negatively charged molecules and large molecules like albumin

What do podocytes do?

Form slit pores which size and charge restrict filtrate

Describe the pressure seen in the glomerulus

High hydrostatic pressure High osmotic pressure (pulling water back in) Bowmans capsule has a much lower hydrostatic pressure Bowmans capsule should not have any osmotic pressure because there shouldn't be any proteins in there

Constriction of the afferents arteriole will ____ GFR whereas constriction of the efferent arteriole will _____ GFR

Decrease Increase

How can major constrion of the efferent arteriole cause a decrease of GFR?

It will build up to conc. Of proteins, increasing the osmotic pressure thus decreasing GFR.

Describe the effect of sympathetic nervous system on GFR

Decreases GFR Constricts afferents

Describe the effect of catecholamines (norepinephrine) on GFR

Decreases GFR Constricts afferents arteriole

Describe the affects of angiotensin 2 on GFR

Prevents a decrease in GFR

Describe the affect of prostaglandins/endothelial derived NO on GFR

Increases GFR Dilates the afferents arteriole

Describe tubuloglomerular feedback

Essential links the sodium chloride conc. Of the DISTAL TUBULE with the constriction state of the arterioles.

What is the role of the macula densa

The macula densa is in the distal tubule and forms the juxtaglomerular complex Detects NaCl levels in distal tubule to alter GFR

What changes does the macula densa do to alter GFR?

Initiates dilation of the afferents arteries and increases release of renin and angiotensin 1 and 2 which causes constrictor of the efferent artiorle

True or false... the scaring of kidneys due to poor control of blood pressure and/or blood glucose levels can permanently lower the GFR

True

When the body osmolarity is high, the kidney will form _____ urine

Concentrated

True or false... glucose is flirted through the glomerulus

True but it is quickly reabsorbed in the proximal tubule

Where is most volume reabsorbed?

Proximal tubule

How are hydrogen ions excreted into the filtrate?

Counter-transport with sodium

In the distal end of the proximal tubule, what is mostly reabsorbed?

Chloride ions. Here, the glucose and amino acids should have already been depleted by reabsorption in the proximal end of the proximal tubule

Sodium amount decreases as we proceed down the nephron but not concentration so much... why?

Because water is being pulled out proportionally

What are the two functionality distinct regions in the loop of henlie?

Thin descending segment and thick ascending segment

What are the thin descending and thick ascending portions of the loop of henlie responsible for?

Thin descending - highly permeable to water Thick ascending - not permeable to water but lots of active transporters to reabsorbed sodium, chloride, and potassium

In the thick ascending segment, what is the primary pump that pumps sodium out of filtrate

Sodium, chloride, potassium cotransporter

The transporters in the thick ascending segment only have a capacity to maintain a _____ mOsm/L difference, but can overcome this by ____ ____

200 Counter current exchange

Where would you find the macula densa (thus the juxtaglomerular apparatus)?

Distal tubule

What are the two distinct cell types found in the distal half of the distal tubule?

Principal cells and intercalated cells

What do principal cells do?

Reabsorb sodium and water from the lumen and secretes potassium into the filtrate. This favors an outward flow of sodium (out of filtrate)

What do intercalated cells do?

Reabsorb potassium and bicarbonate and secrete hydrogen ions into the tubule and can therefore regulate pH

The permeability of the late distal tubule is controlled by ___

ADH

The collecting duct cells are regulated by ____ and are also very efficient at pumping ____ into the lumen

ADH Hydrogen ions Thus they can regulate pH

True or false... the collecting duct is impermeable to urea

False. Some can be reabsorbed thus helping pull water out in the thick ascending segment

What percent of osmotic force is due to urea?

~40%

When ADH levels are high, is more or less urea reabsorbed in the collecting duct? Also... can urea be reabsorbed in the proximal tubule?

More Yes

What cycle links the urea cycle and the citric acid cycle?

Aspartate argininosuccinate shunt of citric acid cycle

Name three pancreatic protease enzymes

Trypsin Chymotrypsin Carboxypeptidase a and b

What kinds of animals get rid of their ammonia by urea, uric acid, or ammonia?

Urea - mammals and sharks Uric acid - birds and reptiles Ammonia - fish and amphibians

Describe the action of glutamine synthase.

Adds a phosphate group by ATP. The. Replaces it with ammonia group m

What enzyme is responsible for converting pyruvate to alanine by converting glutamate to alpha ketogluterate?

Alanine aminotransferase

True or false... the urea cycle is ATP dependent

True