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192 Cards in this Set
- Front
- Back
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378. What vitamin is pyridoxal phosphate?
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Vitamin B6
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379. What is the difference between the active form of pyridoxal and the reaction intermediate?
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1. Active form (PLP) can take up e- and donate them back readily (it has a C=O in it)
2. Reaction intermediate (pyridoaxime phosphate) has an +NH3 instead of the carbonyl |
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380. Through what type of reaction do PLP catalyzed reactions proceed?
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A Schiff base (imine) intermediate
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381. Remember what an imine is?
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meh
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382. From where are the carbon skeletons of amino acids made?
Three places... |
1. Intermediates in glycolysis
2. Intermediates in the citric acid cycle 3. Intermediates in the pentose phosphate pathway |
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383. How are all the pathways in making amino acids regulated?
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They are allosterically regulated by feedback inhibition
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384. How many amino acids can humans make?
Where do we get the others from? |
Humans can make only 10 of the 20 amino acids
We get the rest from our food |
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385. What are the 10 essential amino acids?
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1. Methionine
2. Threonine 3. Lysine 4. Valine 5. Leucine 6. Isoleucine 7. Tryptophan 8. Tyrosine 9. Phenylalanine 10. Histidine |
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386. What are the four functions of nucleotides?
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1. Precursors for RNA and DNA
2. Energy (i.e. ATP) 3. Signaling Molecules (cAMP) 4. Phosphate donors for protein modification |
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387. What are the three basic components of nucleotides?
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1. A pentose
2. A base 3. Phosphates |
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388. What are the five main types of bases?
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1. Adenine
2. Guanine 3. Cytosine 4. Thymine (DNA) 5. Uracil (RNA) |
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389. Which bases are purines and which are pyrimidines?
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Purines: adenine and guanine
Pyrimidines: cytosine, thymine, and uracil |
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390. What are the two types of sugars in nucleotides?
How do the sugars differ? |
The two sugars are ribose and deoxyribose
They differ at C2 in that ribose has a hydroxyl group (-OH) and deoxyribose does not |
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391. To which carbon on the sugar does the base hook itself?
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The base hooks onto C1
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392. What types of phosphates can be on nucleotides?
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A variable number (mono-, di-, and tri-)
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393. What do you call a base + a sugar?
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Nucleoside
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394. How do you name nucleosides?
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Purines: -sine
Pyrimidines: -dine Examples: Adenosine/ Deoxyadenosine Guanosine/ Deoxyguanosine Cytidine/ Deoxycytidine |
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395. What do you call a base + a sugar + a phosphate?
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Nucleotide
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396. How does you name nucleotides?
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-ylate
Examples Adenylate/ Deoxyadenylate Cytidylate/ Deoxycytidylate |
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397. What is a ribonucleotide
Two things... |
1. Contains ribose and uracil
2. Used to make RNA |
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398. What is a deoxyribonucleotide?
Two things... |
1. Contains deoxyribose and thymine
2. Used to make DNA |
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399. What are two important signaling molecules that are nucleotides?
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1. Cyclic AMP (cAMP)
2. Cyclic GMP (cGMP) |
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400. What two ways do you make nucleotides?
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1. In the de novo pathway
2. In the salvage pathway |
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401. What is the de novo pathway?
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Purines and pyrimidines are assembled on an "active ribose" to first make the nucleotides
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402. What is salvage pathway?
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Free bases are recycled by reattachment to an "activate ribose" derivative
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403. What is the "activated ribose" important for the de novo pathway and the salvage pathway?
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5 phosphoribosyl-1-phosphate
*stick a base on it through group transfer *pyrophosphate activates this bond |
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404. What are important de novo intermediates?
Two of them |
1. Inosine: make adenosine and guanosine from it
2. Orotate: make cytosine and uridine from it |
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405. How do you regulate purine biosynthesis?
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Feedback inhibition
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406. What is enzyme is involved in the major control point of purine biosynthesis?
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glutamine-PRPP amidotransferase
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407. How are pyrimidines synthesized?
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They are constructed from carbamoyl phosphate and aspartate
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408. What enzyme catalyzes the reaction between carbamoyl phosphate and aspartate to form carbamoyl-aspartate?
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Aspartate transcarbamoylase (ATC)
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409. How is the carbamoyl phosphate formed?
Two points... |
1. Use HCO3, NH4, and 2ATP
2. Carbamoyl synthetase II is the enzyme used |
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410. What regulates pyrimidine biosynthesis?
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Feedback inhibition of ATC by end product CTP
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411. What happens in nucleotide salvage pathways?
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1. Degrade the nucleotide/nucleoside to a free base
2. Remake the nucleoside by condensation w/ phosphoribosyl pyrophosphate 3. Various kinases rebuild to triphosphate form |
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412. What disease shows us that the salvage pathway is very important?
What can happen from this disease |
Lesch-Nyhan Syndrome where there is a deficiency in the guanine phosphoribosyl tranferase
The disease causes retardation, tendency toward self-mutilation, and death in childhoo |
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413. What are some additional nucleotide complications?
Two things... |
1. Making deoxyribose
2. Making thymidine |
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414. How is deoxyribose made?
Three steps... |
1. Use ribonucleotide reductase
2. Reduce -OH 3. Proceed by means of free radical reactions (very sensitive to free radical inhibition) |
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415. What does ribonucleotide reductase do?
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It uses ribonucleotide diphosphates of the 4 bases (NDP's) and NADPH to make all 4 deoxyribonucleotide diphosphates
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416. How is thymidine synthesized?
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Through a special pathway that has 3 moving parts
(not made as part of the de novo pathway) |
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417. What are the three parts of thymidine biosynthesis?
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1. Thymidine synthase
2. Tetrahydrofolate 3. Dihydrofolate reductase |
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418. What does thymidine synthase do?
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It adds a methyl group to deoxyuracil monophosphate
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419. What does tetrahydrofolate do?
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It provides both the carbon and the electrons
*Note that a carbon is added to dUMP to make dTMP |
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420. What does dihydrofolate reductase do?
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It re-generates the tetrahydrofolate from dihydrofolate using NADPH
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421. What are chemotherapeutic targets?
Two of them... |
1. Inhibit thymidylate synthase using FdUMP
2. Inhibit dihydrofolate reductase with methotrextate aminopterin trimethoprim |
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422. What does inhibiting these targets result in?
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Shut down proliferation of cancer cells because you cannot make DNA
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423. What are folate and s-adenosylmethionine?
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They are carriers of 1 carbon units in one carbon transfers in amino acid and nucleotide biosynthesis
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424. What does folate do?
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It transfers carbon in intermediate oxidation states (-CH2OH, -COOH)
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425. What does s-adenosylmethionine do?
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It transfers reduced carbon (-CH3)
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426. What is tetrahydrofolate?
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H4 folate (cofactor)
*Serine is the source of one-carbon units for tetrahydrofolate |
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427. What is sulfanilamide?
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Antibiotic that competes with p-aminobenzoate in folate synthesis
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428. What is the active part of s-adenosylmethionine (adoMET)
How is it made? |
The active part is +S-CH3 part
AdoMET is made through condensation reation |
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429. List all the cofactors we know and what they transfer.
Eight total! |
1. Thiamin: active acetaldehyde
2. CoA: acetyl 3. Biotin: active carbon dioxide 4. Folate: 1 carbon,various oxidation states 5. S-adenosylmethionine: activated methyl 6. Flavins: e- 7. Nicatinamide: e- 8. Pyridoxal phosphate: NH4 |
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430. What is the first step in amino acid degradation?
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Separation of the amino group from the carbon skeleton
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431. Where does the NH4 go?
Where does the carbon skeleton go? |
NH4 goes to urea cycle
Carbon goes to glycolysis or citric acid cycle |
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432. What are the ultimate two fates of carbons from amino acid degradation?
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1. Become ketone bodies
2. Become glucose |
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433. What are the three ways in nitrogen is excreted?
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1. Ammonia
2. Urea (need water to do this) 3. Uric acid (insoluble; bird crap) |
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434. Why do we need to get rid of ammonia?
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Toxic to the body (causes our pH to vary)
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435. How does our body get rid of ammonia?
Three step process... |
1. Transports excess NH4 to the liver
2. Uses the urea cycle to transform NH4 into the less toxic component urea 3. Excrete urea |
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436. How is excess ammonia in the form of alanine and glutamine transported for disposal?
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1. Alanine is a carrier for NH4 and the carbon skeleton of pyruvate from the skeletal muscle to the liver
2. NH4 is excreted and pyruvate is used to produce glucose which is returned to the muscles |
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437. Why is alanine amino transferase (ALT) in the blood indicative of liver damage?
Three points... |
1. ALT is normally in liver not blood stream
2. Damage to liver releases ALT into the blood serum 3. Assay the level of ALT in the blood to check for liver damage from hepatitis, cirrosis, or chronic alcoholism |
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438. Where is urea made?
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In the urea cycle in the cytosol of liver cells
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439. What two things are hydrolyzed to make urea?
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1. Arginine
2. Ornithine (similar to oxaloacetate in that it accepts material at each turn of cycle) |
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440. Where do the two amino groups that enter the urea cycle come from?
Two places... |
1. Carbamoyl phosphate (formed in the mitochondrial matrix)
2. Asparatate (formed in the mitochondrial matrix) |
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441. What enzyme is used in making carbamoyl phosphate from NH4, HCO3, and 2ATP?
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Carbamoyl phosphate synthetase I
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442. What are the four steps of the urea cycle?
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1. Formation of citrulline
2. Formation of argininosuccinate 3. Formation of arginine 4. Formation of urea |
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443. What are the two steps at which nitrogen is incorporated?
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1. First reaction catalyzed by carbamoyl phosphate synthetase I
2. In the reaction catalyzed by argininosuccinate synthetase (nitorgen enters from aspartate) |
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444. How many molecules of ATP are used to make one molecule of urea?
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3 ATP
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445. Describe the first reaction in the urea cycle?
Three points... |
1. Ornithine and carbamoyl phosphate form citrulline
2. Ornithine transcarbamoylase catalyzes 3. Citrulline passes from mitochondria to cytosol |
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446. What happens to citrulline next?
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It forms a citrullyl-AMP intermediate using argininosuccinate synthatase
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447. Describe the second step of the urea cycle.
Four points... |
1. Second amino group enters from aspartate
2. Form argininosuccinate 3. Argininosuccinate synthatase catalyzes 4. ATP is required |
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448. Describe the third step of the urea cycle.
Three points |
1. Formation of arginine from argininosuccinate
2. Fumarate is released and goes to citric acid cycle 3. Argininosuccinase catalyzes |
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449. Describe the fourth step of the urea cycle.
Three points... |
1. Formation of urea
2. Regenerate ornithine which goes into mitochondria for another round 3. Arginase catalyzes |
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450. What couples the citric acid cycle and the urea cycle?
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The aspartate-argininosuccinate shunt
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451. What two molecules specifically like the urea cycle and the citric acid cycle?
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1. Fumarate
2. α-ketoglutamate |
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452. How is uric acid made?
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1. From purine degradation
2. Made by the mixed function oxigenase xanthine oxidase |
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453. What reaction does xanthine oxidase catalyze?
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Xanthine to uric acid (insoluble)
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454. What do finally end up after the degradation of pyrimidines?
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Urea and after further degradation succinyl-CoA
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455. What is Gout?
What causes gout? |
Inflammatory arthritis (painful and tends to reoccur)
Caused when uric acid crystals are deposited in connective tissue and/or in the fluid that cushions the joint |
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456. How is gout treated?
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Long-term treatment involves blocking the activity of xanthine oxidase
*remember that enzyme is used in uric acid formation from purine degradation |
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457. What inhibits xanthine oxidase?
How does it inhibit? |
Allopurinol
It forms oxypurinol which doesn't dissociate from the active site of xanthine oxidase |
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458. Cells are not islands and need to communicate. What fulfills the necessity of intercellular communication?
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Hormones
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459. What are the glands we need to know?
Nine of them... |
1. Hypothalamus
2. Pituitary 3. Thyroid 4. Parathyroids 5. Adipose tissue 6. Adrenals 7. Pancreas 8. Kidneys 9. Ovaries or Testes |
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460. How do hormones work?
Three step process... |
1. Glands synthesize a hormone which diffuses to target cells
2. The target has a receptor that binds the hormone 3. Hormone/receptor binding results in a response within the target cell that affects the activity of specific enzyme(s) |
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461. What are two basic characteristics of hormone-receptor interactions?
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1. Specificity
2. High affinity *both important since hormones are present at low concentrations |
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462. What is meant by specificity?
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Only the correct hormone binds to the correct receptor
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463. What is meant by high affinity?
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Receptors bind hormones tightly
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464. How can little hormones cause such a big response?
Two ways... |
1. Signal transduction
2. Amplification |
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465. What is amplification?
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When enzymes activate enzymes, the number of affected molecules increases geometrically in an enzyme cascade
(amplify effect of previous step) |
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466. In what ways does hormone/receptor binding lead to signal amplification?
Two ways... |
1. Production of second messenger molecules
2. A kinase cascade |
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467. What do second messengers do?
What are examples of second messengers |
They amplify the signal
Examples are cAMP, cGAMP, IP3, and Ca++ |
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468. What are cAMP and cGMP?
Three things... |
1. Modified purine nucleotides
2. Allosteric regulators 3. Made by adenyly cyclase and guanyly cyclase respectively |
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469. How is Ca++ a second messenger?
Three points... |
1. Normally Ca++ is outside the cell
2. When hormone binds receptor though membrane opens 3. Ca++ enters cell and activates enzymes |
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470. Where do water-soluble hormones bind?
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Bind external receptors on the cell surface (bind outside of the cell; don't enter it directly)
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471. What interaction do water-soluble hormones stimulate?
Two things... |
1. Production of second messenger molecules
2. Kinase cascades |
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467. What are second messengers?
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Intracellular signaling molecules that allosterically regulate critical cellular enzymes
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472. What happens in kinase cascades?
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The message is propagated by sequential phosphorylation of proteins in a signal transduction pathwya
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473. How do water soluble hormones achieve their function?
Two ways... |
1. Changing the activity of a target protein
2. Opening or closing an ion channel |
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471. What are water-soluble hormones?
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Not membrane permeable
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474. What are hydrophobic hormones?
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Lipid-soluble
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475. Where do hydrophobic hormones bind?
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They bind to internal receptors inside the cell since they can diffuse through the cell membrane
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476. What do hormones bound to internal receptors often stimulate?
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Activate the transcription of target genes
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477. What is the purpose of hydrophobic hormones?
Two things... |
1. Make more of an enzyme not change its activity
2. More of a long-term acting hormone |
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478. What are the different groups of hormones?
Three groups... |
1. Water soluble
2. Lipid soluble (hydrophobic) 3. Intracelluar |
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479. What are three examples of water soluble hormones?
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1. Peptide hormones
2. Catecholamine 3. Eicosanoids |
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480. What are two examples of lipid soluble hormones?
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1. Steroids
2. Thyroid |
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481. What is an example of an intracellular hormone?
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Nitric oxide
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482. Describe peptide hormones?
Four points... |
1. Amino acid chains processed from longer precursors
2. Stored in internal vesicles until released into intercellular space 3. Bind cell surface receptor to start signal transduction cascade 4. Work very rapidly |
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483. What are three examples of peptide hormones?
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1. Insulin
2. Glucagon 3. Hormones of pituitary and hypothamus |
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484. What do catecholamine hormones mediate?
What else do they do? |
They mediate stress response
They act as neurotransmitters or hormones that cause secondary messenger production |
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485. What are catecholamine hormones derived from?
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They are derived from catechol via tyrosine in the brain and adrenal gland
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486. What do eicosanoids cause?
Three things... |
1. Smooth muscle contraction
2. Inflammation 3. Blood clotting |
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487. How are eicosanoids made?
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They are made from arachidonate on an as needed basis by most tissues of the body
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488. How do eicosanoids act?
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They act as paracrine hormones on adjacent cells via cell surface receptors
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489. How far do eicosanoids hormones act?
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They act short-range and have a local affect
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490. What are steroid hormones produced from?
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Cholesterol
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491. Where are steroids produced?
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In adrenal cortex
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492. What is the function of steroid hormones?
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They act on nuclear receptors that induce transcription of target genes
*long-term effects |
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493. How do steroid hormones travel to their target cells?
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They travel through the blood plasma bound to carrier proteins
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494. What are thyroid hormones produced from?
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The precursor thyroglobulin-tyr
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495. What is essential to making thyroid hormones?
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Iodine
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496. What is the regulated step in thyroid hormone synthesis?
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Conversion of iodinated Tyr residues to the active hormone T3 by proteolysis
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497. What is the function of thyroid hormones?
Two things... |
1. Regulate transcription through nuclear receptors
2. Regulators of energy metabolism (stimulate in liver and muscles by increasing expression of certain gene) |
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498. How is nitric oxide formed?
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Synthesized from molecular oxygen and nitrogen of arginine in reaction catalyzed by NO synthase
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499. What is nitric oxide?
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Relatively stable free radical (it's a gas!)
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500. What is the function of nitric oxide?
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Activates guanyly cyclase to make cyclic GMP (a secondary messenger)
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501. Does nitric oxide travel far?
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No, it works near point of origin
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502. How are hormones regulated?
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In a hierarchical manner
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503. What is the top of the hierarchy?
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Hypothalamus
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504. What does the hypothalamus do?
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It monitors the status of the body and responds by generating any number of specific releasing hormones
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505. What do the specific releasing hormones do?
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They cause the anterior pituitary to make specific tropins that regulate specific endocrine glands
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506. What do the specific tropins do?
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They activate the specific endocrine gland to make specific hormoones
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507. Last but not least, what do the hormones do?
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They target specific cell types
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508. What are the master regulatory glands?
Two glands... |
1. Hypothalamus
2. Pituitary |
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509. What is the main function of these two glands?
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To act as the interface between the nervous system and the endocrine system
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510. When the hormone binds the receptor, in what ways can the interaction affect the cell?
Three ways... |
1. Open ion channels
2. Activate a signal transduction cascade that activates/represses specific enzymes 3. Induce transcription of target gene(s) |
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488. What are paracrine hormones?
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They are released into the extracellular space and diffuse to neighboring target cells
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511. How does acetylcholine hormone affect the cell?
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It's a neurotransmitter that opens ion channels
*binding to receptor causes the affect |
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512. How does the binding of insulin (a peptide hormone) affect the cell?
Three points... |
1. Binding causes phosphorylation
2. A kinase cascade is used to activate glycogen synthase 3. Signal transduction and amplification is illustrated |
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513. What does the peptide hormone glucagon use to activate glycogen phosphorylase?
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Second messengers (cAMP)
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514. What is the liver responsible for?
Four jobs... |
1. Keeping blood sugar levels constant
2. Degrading FA's to ketone bodies when glucose supply is low 3. Remove excess NH4 through urea cycle 4. Regenerate glucose from lactate following exercise |
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515. What do the muscles use for mechanical work?
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ATP
*But different fuels are used for ATP synthesis for various kinds of activity |
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516. What is used for light activity or rest?
Three fuels... |
1. Fatty acids
2. Ketone bodies 3. Blood glucose *release CO2 |
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517. What is used for bursts of heavy activity?
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Muscle glycogen
*release lactate |
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518. What else can be used for bursts of heavy activity?
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Phosphocreatine
*release creatine |
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519. What is phosphocreatine?
Two things |
1. A storage form of ATP in the muscles
2. Able to generate ATP quickly |
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520. How is ATP generated by phosphocreatine?
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It's dephosphorylated and gives the Pi to ADP forming ATP
*During recovery creatine is phosphorylated to reform phosphocreatine |
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521. Describe adipose tissue?
Two points... |
1. Amorphous
2. Distributed throughout the body |
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522. What is the function of adipose tissue?
Two jobs... |
1. Store triacylglycerides (TAG's) arriving from liver or intestine
2. Synthesize, store, and mobilize TAG's |
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523. What percent of mass is mostly TAG's in a fit person?
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15% the mass of a fit person
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524. What does the brain use to maintain electrical activity?
Two molecules... |
1. Glucose (normal diet)
2. Ketone bodies (starvation) |
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525. What can lapses in blood glucose level to the brain?
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Cause permanent brain damage (even momentary lapses)
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526. What is the role of blood?
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It's the main transport system for food and waste
*Blood glucose levels must be tightly controlled |
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527. Where does blood carry food?
Where does it carry waste? |
Blood carries food (O2, glucose, ketone bodies) to peripheral tissue
Blood carriers waste (CO2, excess NH4) to liver and lungs |
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528. What happens in the well-fed state liver?
First three things |
1. After calorie rich meal, glucose, FA's, and AA's enter the liver
2. Insulin is released (response to high blood glucose levels) 3. Glucose uptake by tissues |
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529. What happens to the glucose?
Three fates... |
1. Some is exported to the brain
2. Some is exported to fat and muscle tissues 3. Some stored as glycogen |
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530. How is some glucose exported to fat and muscle tissues?
Three parts... |
1. Excess glucose in the liver is oxidized to acetyl-CoA
2. Acetyl-CoA synthesized to FA 3. Export as TAG's in VLDL to fat and muscle tissue |
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531. What are amino acids used for in the well-fed state liver?
Two things... |
1. Metabolize for protein synthesis
2. Metabolize to α-keto acids and then urea |
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532. What happens to the fat in the well-fed state liver?
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They are not really metabolized and just go to adipose tissue
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533. What is the order of use of molecules by the well-fed liver?
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Carbohydrates, TAG, and then proteins (amino acids)
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534. What happens in the fasting liver?
Four things... |
1. Liver becomes principal source of glucose for brain
2. Break glycogen down and ship glucose to brain 3. Once all possible glucose is used, ketone bodies will be used 4. When you run out of fat, proteins in your muscles will be metabolized |
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535. What hormones are used for short-term, fast acting regulation of metabolism?
Three hormones.... |
1. Insulin: stimulates energy storage
2. Glucagon: stimulates energy release 3. Epinephrine: stimulates energy release |
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536. What hormones are used for slow acting regulation of metabolism?
Two hormones |
1. Cortisol: activity similar to glucagon
2. Thyroid hormone: activity similar to insulin |
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537. What stimulates the release of epinephrine?
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Stress stimulates the release of epinephrine from the adrenal glands
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538. What is epinephrine important for?
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Fight or flight response
(quick energy) |
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539. What do epinephrine's activities include?
Four things... |
1. Increasing O2 to muscles
2. Stimulating an increase in blood glucose 3. Increased β-oxidation 4. Stimulates glucagon release, inhibits insulin release |
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540. Describe cortisol.
Three points |
1. Steroid hormone
2. Made by adrenal gland 3. Used for long-term situation |
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541. What does cortisol do?
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Adjust to stress by stabilizing blood glucose levels in a slower manner by inducing synthesis of various enzymes
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542. Cortisol produces enzymes needed for...
Three reactions |
1. Gluconeogensis
2. β-oxidation 3. Break down of proteins for energy |
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543. What does the thyroid hormone do?
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It stimulates the production of adipose tissues when times are good (many of the same things insulin does)
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544. How does the thyroid hormone work?
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It works through induction of transcription of enzymes needed for fat synthesis (i.e. fatty acid synthase, acetyl-CoA carboxylase)
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545. What does lack of the thyroid hormone cause?
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Cretinism which is characterized by severe mental and physical retardation
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546. How long does your glycogen supply last?
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12-24 hours
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547. How long does your triacylglyceride (TAG) supply last?
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2.5 months for a fit person
maybe up to 4 years for a chunky beefy person...ugh |
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548. How long does your protein supply last?
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nasty cannibal.
2 weeks if you're lucky |
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549. What is type 1 diabetes?
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results from an inability to make insulin
very severe treated by injection of insulin |
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550. What is type 2 diabetes?
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results from a partial or complete inability to respond to insulin (called insulin resistant)
often late onset treatment by diet |
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551. What is odd about diabetes?
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With both types of diabetes although you're well fed, your body thinks it's starving
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552. What are some metabolic characteristics of diabetes?
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High blood glucose
High [glucose] in urine, resulting in excessive thirst and much piss Increased degradation of TAGs with overproduction of ketone bodies and lowering of blood pH |
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553. What are some diseases, conditions of diabetes down the road?
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heart disease
strokes circulation problems nerve damage |
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554. How does the glucose tolerance test work?
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Fast the night before and then eat lots of glucose
Measure glucose levels every 30 minutes afterwards for several hours If blood glucose levels don't decrease with time, person has diabetes |
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555. What are most people with Type II diabetes like?
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CHUNKY!!!
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556. How do you treat diabetes?
Four ways... |
1. Insulin injection (type I)
2. Control diet (avoid simple sugars) 3. Exercise 4. Drugs are available to stimulate insulin production |
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557. Obesity: BMI
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BMI below 25: normal
BMI bwt 25 and 30: overweight BMI over 30: Obsese |
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558. What is the basis of the lipostat theory?
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1. You're hungry
2. You eat something 3. You are no longer hungry *body regulates mass so you don't become beefy chunky |
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559. What is the lipostat theory
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The idea that adipose tissue secrets a hormone that inhibits appetite and increases energy consumption
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560. What are the candidates for the lipostat theory?
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Leptin
Adiponectin Obestatin |
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561. What is Leptin?
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Hormone secreted by adipose tissue that controls weight
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562. What is Adiponectin?
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An adipose produced hormone
Peptide hormone that increases FA uptake and β-oxidation in muscles via inhibition of acetyl-CoA carboxylase |
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563. Have we solved obesity?
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No
Most obese people have increased levels of leptins Mice lacking adiponectin have normal weight WTF |
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564. What are ghrelin and obestatin?
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Small hormones secreted by the lining of your stomach
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565. What is ghrelin?
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Appetite stimulant
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566. What is obestatin?
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An appetite suppressant
In mice, exogenous obestatin caused them to lose weight |
