Fnm 007 An Overview Of Metabolism

Front 1

Oxidation of complex substrates to CO2 is generally exhibited by catabolic pathways T/F

Back 1

T

Front 2

Reduction of oxygen to water is generally exhibited by catabolic pathways T/F

Back 2

T

Front 3

Anabolic pathways are generally regulated by the need for ATP and/or availability of the substrate T/F

Back 3

F - catabolic pathways are regulated in this way

Front 4

Catabolic pathways are generally involved in the snythesis of complex products from simpler substrates T/F

Back 4

F- this describes anabolic pathways

Front 5

Anabolic pathways require ATP T/F

Back 5

T - anabolic pathways involve the build up from smaller, simpler substrates

Front 6

Catabolic pathways are often reductions, rather than oxidations T/F

Back 6

FALSE, anabolic pathways are more often reductions (CORA)

Front 7

Anabolic pathways are generally regulated by the need for the end-product T/F

Back 7

T


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Front 8

What are 'central' pathways?

Back 8

Pathways that may serve catabolic or anabolic purposes

Front 9

Give an example of a 'central' pathway (one which may serve catabolic or anabolic purposes)

Back 9

The citric acid cycle

Front 10

Intermediates in catabolic pathways may be important substrates for anabolic pathways T/F

Back 10

T

Front 11

The precursor to this coenzyme is adenine

Back 11

ATP

Front 12

The function of this coenzyme is energy metabolism

Back 12

ATP

Front 13

The precursor to this coenzyme is panthothenic acid

Back 13

CoA

Front 14

The function of this coenzyme is acyl transfer

Back 14

CoA

Front 15

The precursor to these coenzymes is vitamin B(2)

Back 15

FAD (flavin adenine dinucleotide)

FMN (flavin mononucleotide)

Front 16

The function of these nucleotides is oxidation

Back 16

FAD (flavin adenine dinucleotide)

FMN (flavin mononucleotide)

Front 17

The functions of these coenzymes are oxidation and reduction

Back 17

NAD (nicotinamide adenine dinucleotide)

NADP (nicotinamide adenine dinucleotide phosphate)

Front 18

The precursor to these coenzymes is naicin

Back 18

NAD (nicotinamide adenine dinucleotide)

NADP (nicotinamide adenine dinucleotide phosphate)

Front 19

Give the four fuels that enter the circulation from the gut.

Back 19

Glucose
Amino acids
Fatty acids
Triacylglycerols

Front 20

These two fuels are absorbed into the portal circulation, and the liver controls the amounts entering peripheral circulation for other tissues

Back 20

Glucose and amino acids

Front 21

These two fuels are absorbed into the lymphatic system and enter the bloodstream at the thoracic duct (therefore available for peripheral tissues without control by liver)

Back 21

Fatty acids and triacylglycerols

Front 22

Alpha cells of the pancreas secrete glucagon T/F

Back 22

T

Front 23

Increase in glucose and AAs in portal blood stimulates insulin secretion T/F

Back 23

T - This insulin secretion is done by the beta-cells of the pancreas

Front 24

Increase of glucose in the portal circulation increases glucagon secretion T/F

Back 24

F - it suppresses glucagon secretion by alpha-cells of the pancreas

Front 25

Insulin stimulates upate and utilisation of glucose by peripheral tissues T/F

Back 25

T

Front 26

Insulin inhibits uptake of amino acids by tissues T/F

Back 26

F - Stimulates uptake of AAs by tissues, leading to increased protein synthesis

Front 27

What is the glucose that is in excess of immediate requirements used for? (2)

Back 27

Synthesis of glycogen in LIVER and MUSCLE

Synthesis of fatty acids and hence triacylglycerols in the LIVER and ADIPOSE tissue

Front 28

After eating, metabolic rate increases by 10% or more. Why?

Back 28

Energy cost of:

Glycogen synthesis
Triacylglycerol synthesis
Increased protein synthesis (because the insulin released stimulates uptake of AAs into the tissues (: )

Front 29

Glucagon stimulates the breakdown of glycogen in the liver to release glucose into the circulation T/F

Back 29

T

Front 30

Muscle glycogen can also be used as a direct source of blood glucose T/F

Back 30

FALSE

Front 31

Glucagon stimulates breakdown of triacylglycerol in adipose tissues T/F

Back 31

T

Front 32

Glucagon results in fatty acids and glycerol being released into the circulation T/F

Back 32

T

Front 33

However, glucagon does not stimulate the synthesis of glucose from AAs in the liver, kidney and small intestine T/F

Back 33

F, it does

Front 34

The brain can use fatty acids as a fuel T/F

Back 34

F, only tissue that cannot (RBCs also can't)

Front 35

The liver can oxidise fatty acids faster than needed for its own energy requirements T/F

Back 35

T - It synthesises ketones (acetoacetate and hydroxybutyrate) for release into circulation for use by other tissues

Front 36

In the fasting state, how long can the total liver and muscle glycogen meet requirements for?

Back 36

12-18 hours

Front 37

The brain cannot use keytones, even in prolonged starvation (more than 10-14 days) T/F

Back 37

F

Front 38

After running out of glycogen, remove of AAs is necessary for gluconeogenesis.

Back 38

Hence the net loss of tissue protein.