Intro to metabolism

Question 1

Predict the relative caloric needs of

an average 22 year old moderately active male
an average 22 year old male victim of a major burn
3. an average 22 year sedentary male
4. an average 32 year old sedentary female
5. an average 60 year old active female

a. 1>2>3>4>5
b. 1>3>2>4>5
c. 1>3>4>5>2
d. 2>1>3>5>4
e. 2>1>3>4>5

Answer 1

d. 2>1>3>5>4

Question 2

Where Do Polysaccharides Get Digested?

Answer 2

mouth, intestine, colon

Question 3

Which of the following describes the action of a-amylase?

A.  It cleaves glucose a 1→4 glucose bonds but not glucose a 	1→6 glucose bonds.

 B. It occurs in the brush border membrane of 	intestinal epithelial cells.

C.  It digests starch completely to the monosaccharide 	glucose. 

D.  Its digestion products are all short linear chains of 	glucose. 

E.  Salivary amylase remains active in the stomach.

Answer 3

A. It cleaves glucose a 1→4 glucose bonds but not glucose a 1→6 glucose bonds.

Question 4

Active transport of glucose occurs in which tissue:

A. Brain occurs because brain requires glucose as fuel

B. Kidney to prevent loss of glucose to the urine

C. Liver to help lower blood glucose levels

Muscle to support exercise

E. Red blood cells because they have no mitochondria

Answer 4

B. Kidney to prevent loss of glucose to the urine

Question 5

Insulin increases the transport of glucose from the blood into:

A. Brain cells

B. Kidney cells

C. Liver cells

    D. Muscle cells

E. Red blood cells

Answer 5

D. Muscle cells

Question 6

fuel is stored as _____ limited

Answer 6

glycogen

Question 7

fuels is stored as ______ limited but more

Answer 7

protein

Question 8

fuels is stored as ________ limitless

Answer 8

triglycerides

Question 9

enzymes that have same function but different structure

Answer 9

isozymes

Question 10

why is metabolism different in tissues? (3)

Answer 10

(1) carry out different processes
(2) use/produce different fluids
(3) isozymes

Question 11

synthesis

Answer 11

anabolism

Question 12

degradation

Answer 12

catabolism

Question 13

refers to the interconversions of molecules of the metabolome

Answer 13

metabolism

Question 14

metabolism is controlled by proteins _____, which in turn results from information encoded in DNA and RNA, ______ and _______

Answer 14

controlled by the proteome and encode the genome and transcriptome

Question 15

lacks glucose-6-phosphatase

Answer 15

muscle

Question 16

example of isozymes

Answer 16

hexokinase and glucokinase

Question 17

pathways may be _____ like glycolysis, ______ like TCA, or _______ like fatty acid synthesis

Answer 17

linear, cyclic, or spiral

Question 18

what is expected to occur at steps that are out of equilibrium?

Answer 18

regulation by altering activities of the enzyme catalyzing those steps.

Question 19

enzyme regulation can occur by ______ small molecules, _______ post-translational modification, _______ changes in enzyme amount, or _______ compartmentalization

Answer 19

• allosteric regulation
• phosphorylation
• synthesis/degradation
• fatty acid oxidation in mitochondria

Question 20

Hormones such as ___________ can remodel enzyme activites to alter metabolism

Answer 20

insulin in the well-fade state

Question 21

caloric intake of fat

Answer 21

9 cal/gram

Question 22

caloric intake of protein

Answer 22

4 cal/gram

Question 23

caloric intake of carbohydrate

Answer 23

4 cal/gram

Question 24

what does the glycemic index of food estimates

Answer 24

its effect on blood glucose and insulin levels

Question 25

why is cellulose, a polyglucose like amylase is not a useful source of food?

Answer 25

it has beta linkages that our enzymes cannot cleave

Question 26

in kidney and intestine glucose/galactose transport is

Answer 26

active with a sodium co-trasnport | SGLT1,2

Question 27

glucose is transported by ______ in most cells

Answer 27

facilitated diffusion

Question 28

Glut 2 important in

Answer 28

liver

Question 29

Glut 4 important in

Answer 29

muscle, fat and white cells

Question 30

Glut 4 is regulated by

Answer 30

insulin leading to increased uptake of glucose

Question 31

carbohydrates enter portal circulation with the ______ as an initial destination

Answer 31

liver

Question 32

Causes of malabsorption: (4)

Answer 32

(1) lactase deficiency (2) transported deficiency (3) defects in SGLT1 (4) decreased intestinal surface area

Question 33

does serine syntheis & degradation go on identical paths?

Answer 33

NO!!!!

Question 34

allosteric inhibition or stimulation by small molecules is

Answer 34

immediate

Question 35

covalent modification like phosphorylation is

Answer 35

rapid, allows for signaling control

Question 36

adaptive response by regulation of the amount of enzyme

Answer 36

slower, inhibition/stimulation of gene transcription | protein degradation/stabilization

Question 37

compartmental separation

Answer 37

specific tissues important for specific processes

Question 38

hormone of the well-fed state

Answer 38

insulin

Question 39

hormone of the starved state

Answer 39

glucagon

Question 40

hormone of acute stress

Answer 40

epinephrine

Question 41

hormone for longer term reponses

Answer 41

cortisol

Question 42

alpha-amylase digestion yields

Answer 42

maltoses and Limit dextrins

Question 43

bacteria digest un absorbed carbs

Answer 43

colon

Question 44

glucagon, epinephrine and cortisol are

Answer 44

glucose mobilizers or glucose synthesis promoters

Question 45

activity beats age!!! keypoint!

Answer 45

active older needs more calories than younger

Question 46

(3) sources of sugar

Answer 46

(1) monosaccharides (2) disaccharides (3) polysaccharides

Question 47

alpha-amylase: released by and breaks what?

Answer 47

released by salivary glands of mouth and breaks 1-4 linkages in polysaccharides

Question 48

why is there no carbohydrate digestion in the stomach?

Answer 48

low pH of stomach inhibits alpha-amylase

Question 49

what does the Gallbladder release?

Answer 49

CCK

Question 50

CCK stimulates

Answer 50

Alpha-amylase

Question 51

who will further release alpha-amylase?

Answer 51

pancreas

Question 52

intestinal epithelium releases

Answer 52

lactase, sucrase, isomaltase and glucoamylase

Question 53

cleaves 1-6 linkages

Answer 53

isomaltase

Question 54

what happens in lactase deficiency?

Answer 54

lactose that is not digested in stomach moves into lower GI

Question 55

Lactase deficiency: bacteria digest lactose giving ____ as a by product; lactose digested into ______ and _______

Answer 55

GAS, and digested into lactic acid and fatty acid

Question 56

What does lactic acid and FAs create?

Answer 56

fluid load, has osmotic effect which drags water out of cells causing diarrhea

Question 57

innapropriate release of pancreatic anylase gives

Answer 57

pancreatic disease also seen in CF

Question 58

genetic defects can give improper enzyme resulting in

Answer 58

congenital sucrase or isomaltase deficinecy

Question 59

transporter insufficiency of SGLT1 can results in

Answer 59

improper fructose absorption

Question 60

damage to brush border causes

Answer 60

low surface area

Question 61

polysaccharide that remains undigested

Answer 61

fiber

Question 62

undigested polysaccharide gives

Answer 62

bulky stool, affects intestinal mobility, lowers cholesterol and absorbs carcinogens

Question 63

simple diffusion

Answer 63

diffusion down concentration gradient

Question 64

when does simple diffusion occur

Answer 64

only with rare sugar at [low]

Question 65

facilitated diffusion

Answer 65

increases rate of transport, but no energy used

Question 66

facilitated diffusion: Glut 5 on intestinal lumen

Answer 66

move fructose into cells

Question 67

facilitated diffusion: Glut 2 moves

Answer 67

sugar in cell out into blood

Question 68

active transport

Answer 68

increased rate of transport, against gradient and uses energy

Question 69

SGLT1

Answer 69

actively transport glucose and galactose

Question 70

expenditure of ATP to maintain concentration gradient of ______ allows glucose and galactose to move ________________

Answer 70

expenditure of ATP to maintain concetration gradient of Na+ allows glucose and galactose to move down their gradient

Question 71

SGLT2

Answer 71

used in kidney to actively pump glucose back into blood from kidney

Question 72

active transport: Glucose absorption

Answer 72

SGLT1

Question 73

active transport: Glucose reabsorption

Answer 73

SGLT2

Question 74

only transporter sensitive to insulin

Answer 74

Glut 4

Question 75

transporter of glucose into liver

Answer 75

Glut 2

Question 76

Fanconi-Bickel syndrome

Answer 76

defect in Glut 2

Question 77

what happens in Fanconi?

Answer 77

liver cannot uptake glucose giving postprandial hyperglycemia

Question 78

after glucose meal

Answer 78

blood glucose increases then eventually will level off

Question 79

food with high glycemic index will have

Answer 79

more insulin release

Question 80

diabetes means low insulin levels which results in

Answer 80

higher resting glucose, higher glycemic index, and slower return to base levels

Question 81

ubiquitous

Answer 81

hexokinase

Question 82

found in liver and Beta-pancreatic cells

Answer 82

glucokinase

Question 83

type of diabetes associated with faulty glucokinase

Answer 83

MODY

Question 84

why does the liver acts as glucose filter to normalize sugar levels?

Answer 84

because glucokinase has high Vmax

Question 85

Both hexokinase and glucokinase

Answer 85

phosphorylates sugars to bring them into cell

Question 86

has high maximal activity and thus can bring large amount of glucose into cells

Answer 86

glucokinase