Carbohydrate Metabolism Flashcards by Olivia Holmes

What three areas of the body does the metabolism of carbohydrates occur?

Mouth: start point of carbohydrate breakdown
Small intestine: main area of carbohydrate digestion
Liver: begins process of glycolysis

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What area of the body does the process of digestion begin? The process of digestion begins in the mouth, with enzyme α-amylase beginning to break down the complex polysaccharide, or, starch.

Salivary α-amylase catalyses the hydrolysis of α-glycosidic bonds of starch, producing smaller polysaccharides and disaccharide (maltose).
Fructose and galactose are converted into compounds that enter the same pathway as glucose: glycolysis.

The mouth

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The enzyme α-amylase breaks down the complex polysaccharide in the ______

mouth at the beigging of digestion

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In the mouth, salivary α-amylase catalyses the ________ of α-glycosidic bonds of starch, producing smaller polysaccharides and disaccharide (maltose).

Hydrolysis

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Majority of carbohydrate digestion occurs in the ____

The Small Intestine

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In the small intestine, Pancreatic α-amylase catalyses the ________ of α-glycosidic bonds in polysaccharides to produce maltose.

hydrolysis

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In the small intestine, enzymes break down _________ (maltose, sucrose and lactose) into _________ glucose, fructose and galactose which are absorbed via active transport into bloodstream; then transported into the ______.

disaccharides, monosaccharides, liver

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In the small intestine the disaccharide maltose is broken down into _____ and _______ with the _______ enzyme

Glucose and glucose with maltase enzyme

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In the small intestine the disaccharide sucrose is broken down into _____ and _______ with the _______ enzyme

Fructose and glucose with sucrase enzyme

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In the small intestine the disaccharide lactose is broken down into _____ and _______ with the _______ enzyme

Glucose and galactose with lactase enzyme

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Monosaccharides glucose, fructose and galactose enter the blood via ____________ which is then transported to the liver

active transport

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Active transport requires_______ and a _______.

energy (ATP) and transporter protein (carrier)

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Monosaccharides in the intestine travel across the _________ of the small intestine into the blood.

epithelium

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Once in the blood, monosaccharides are then transported to the liver, which modifies glucose, fructose and galactose to enter into _________

glycolysis

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The hormone _______ promotes the movement of glucose into the cell from the blood.

insulin

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What are the two hormones that play important roles in this process of carbohydrate breakdown

Insulin and glucagon

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What is insulins function?

Functions to bring glucose into the cell from the blood and assists in lowering the blood glucose level.

Promotes metabolic reactions that use glucose: glycolysis and glycogenesis.

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What is Glucagons function?

Functions to move glucose out of the cells into the blood and assists in increasing the blood glucose level.

It promotes glucose making reactions: glycogenolysis and gluconegenesis.

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The release of insulin is triggered by _____ blood-glucose levels

High

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The release of glucagon is triggered by _____ blood-glucose levels.

Low

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What are the five steps of Carbohydrate Metabolism?

Digestion pathway
Glycogenesis
Glycogenolysis
Glycolysis
Gluconeogenesis

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What step of the carbohydrate metabolism does the following belong to?

Glucose polysaccharides are digested into monosaccharides (glucose, fructose and galactose). The basic units are absorbed into the bloodstream.

Digestion pathway

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What step of the carbohydrate metabolism does the following belong to?

Any excess glucose that is not used for energy at that time is sent into the liver and muscles to be synthesised, as a storage form of glucose, glycogen, by glycogenesis.

Glycogenesis

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What step of the carbohydrate metabolism does the following belong to?

Any time in between meals when glucose is required, they will be broken down again in glycogenolysis to release glucose. And, any time there is no or very low glucose in the blood for energy, non-carbohydrates sources of molecules can also be used to synthesise glucose for energy.

Glycogenolysis

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What step of the carbohydrate metabolism does the following belong to? The second series of reactions is the glycolysis that will break the glucose down to pyruvate. That's the final product of glycolysis.

Glycolysis

What step of the carbohydrate metabolism does the following belong to? Generation of glucose from certain non-carbohydrate carbon substrates (Pyruvate) which is activated by Glucogen

Gluconeogenesis

________ is the catabolic (breakdown of complex molecules to simple ones) pathway that takes place in the cytosol, in which glucose (C6) is broken down into two molecules of pyruvate (C3)

Glycolysis

glycolysis is activated by _______ and deactivated by _____

insulin and deactivated by glucagon

Is glycolysis an oxidisation process?

Yes

Glycolysis is a ______-step process

Ten

In glycolysis the first five steps are called the _______ stage, where the body will consume ATP, and the second five steps are the ______-off phase, where ATP is released

preparatory stage and pay-off phase

``` Name the molecules in Glycolysis: GROSS GUYS FAVOUR BIG BUTTS GOOD BOYS PREFER PRETTY GIRLS IN PINK PYJAMAS ```

``` GROSS - Glucose GUYS - Glucose-6-phosphate FAVOUR - Fructose-6-phosphate BIG BUTTS - Fructose-1-6-bisphosphate GOOD - Glyceraldehyde-3-phosphate BOYS - 1-3-bisphosphoglycerate PREFER - 3-phosphoglycerate PRETTY GIRLS IN - 2-phosphoglycerate PINK - phospho-enolpyruvate PYJAMAS - Pyruvate ```

``` Name the enzymes in Glycolosis: Helen Paints Pictures Along the Training Grounds Praying People Enjoy Paintings ```

``` Helen - Hexokinase Paints - Phosphoglucose isomerase Pictures - Phosphofructokinase-1 Along the - Aldolase Training - Triose- Phosphate isomerase Grounds - Glyceraldehyde-3-phosphate dehydrogenase Praying - Phosphoglyceratekinase People - Phosphoglyceratemutase Enjoy - Enolase Paintings - Pyruvatekinase ```

In Glycolosis the C6 stage is the energy _________ stage, where 2ATPs are __________.

consumption stage, consumed

Glycolosis takes place in the _______

cytosol

Glycolosis is the ____________ pathway following digestion

Second

In Glycolosis glucose six carbon is split into three carbon pyruvate molecules in the C__ stage.

In Glycolosis the C3 stage is the energy _________ stage, where 4 ATPs are __________.

generation, produced

In every glycolysis reaction we gain __ ATP ( __ ATP produced in pay-off phase and __ TP used in the preparatory phase).

2, 4, 2

In Glycolosis the C6 stage has steps ___ through ____.

1, 3

In Glycolosis the C3 stage has steps ___ through ____.

5, 10

C3 stage of Glycolysis produces two molecules of NADH that is required in the electron transport chain. It does this by transferring ___________ to molecules of NAD+.

high energy electrons

Galactose enters Glycolosis at step _____

Fructose enters Glycolosis at step _____

Regulation of Glycolysis using particular enzymes at steps ____, ____ and ____

one, three and ten

Pyruvate is produced in _________ and has ______ fates.

Glycolysis, three

Pyruvate will be used to create ATP when oxygen is ______. This is A_______

present, Aerobic

Pyruvate will be used to create lactate when oxygen is ______. This is A_______

isn't present, Anaerobic

Pyruvate will be used to create _____ only in some microorganisms.

ethanol

When pyruvate is converted to Acetyl CoA in the presence of O2 it then enters the ________

citric acid cycle (CAC)

Finish the steps of Pyruvate Oxidation 1 - Pyruvate transported from _______ 2 - Moves through both mitochondrial membranes to the ______ 3 - Catalysed by _______ _______ _______ 4 - Oxidised and _________ to form Acetyl CoA 5 - Enters the ______ _______ ______

``` 1 - Cytosol 2 - Matrix 3 - pyruvate dehydrogenase complex 4 - decarboxylated 5 - citric acid cycle ```

In oxygen-poor environments pyruvate is quickly reduced to ______ catalysed by lactate dehydrogenase

lactate

The Cori Cycle enables us to convert the lactate we create in ______ _______ back to pyruvate in the ______.

anaerobic respiration, liver

In The Cori Cycle once lactate is converted to pyruvate it can then be converted back again to glucose; through _____________ (the reverse process of glycolysis)

gluconeogenesis

The Citric Acid Cycle (CAC) is a series of biochemical reactions in which the acetyl portion of acetyl coenzyme A is _________ to carbon dioxide and the _______ coenzymes FADH2 and NADH are produced

oxidised, reduced

Name two important types of reactions which take place in the CAC: - The _________ of NAD+ and FAD to produce NADH and FADH2 - The _________ of citric acid to produce carbon dioxide

reduction, decarboxylation

The CAC takes place in the __________ matrix, inside the _______ ________ membrane

mitochondrial, double mitochondrial

Acetyl-CoA comes from glucose via pyruvate in g_______, from lipids in b________ o__________, and from protein c________ s_______

glycolysis, beta-oxidation, carbon skeletons

The purpose of the CAC is harvesting of h______ e______ e______

high energy electrons

What is Step one, condensation's, purpose in the CAC?

Acetyl-CoA combines with Oxaloacetate to form Citrate

Steps in the CAC 1. C__________ - Formation of C________ 2. I___________ - Formation of I_________ 3. O________ and D________ of I________ 4. O________ and D_________ of α-K_________ 5. P_________ 6. O______ of S________ 7. H________ of F________ 8. O__________ of L-M________

1. Condensation - Formation of Citrate 2. Isomerisation - Formation of Isocitrate 3. Oxidation and Decarboxylation of Isocitrate 4. Oxidation and Decarboxylation of α-Ketoglutarate 5. Phosphorylation 6. Oxidation of Succinate 7. Hydration of Fumarate 8. Oxidation of L-Malate

What is Step three, Oxidation and Decarboxylation, purpose in the CAC?

First redox reaction for Oxidation and Decarboxylation of Isocitrate

What is Step four, Oxidation and Decarboxylation, purpose in the CAC?

Second redox reactions for Oxidation and Decarboxylation of α-Ketoglutarate

What is Step five, Phosphorylation, purpose in the CAC?

Formation of Succinate and GTP

What is Step six, Oxidation, purpose in the CAC?

Third redox reaction for Oxidation of Succinate

What is Step seven, Hydration, purpose in the CAC?

Hydration of Fumarate to produce L-Malate

What is Step six, Oxidation, purpose in the CAC?

Third redox reaction for Oxidation of Succinate

What is Step seven, Hydration, purpose in the CAC?

Hydration of Fumarate to produce L-Malate

What is Step eight, Oxidation, purpose in the CAC?

Fourth redox reaction for Oxidation of L-Malate

``` One complete cycle of CAC produces: _ CO2 _ GTP _ NADH _ FADH2 ```

2 CO2 1 GTP 3 NADH 1 FADH2

The rate at which the CAC operates is controlled by the body’s needs for energy (ATP). - High NADH levels will ______ the citric acid cycle. - When ATP supply is high: ATP _____ citrate synthase (needed for Step 1 of CAC). - When ATP levels are low: ADP ________ citrate synthase (the CAC speeds up).

inhibit inhibits activates

Define Synthesis in Glycogen Synthesis and Degradation

The process of building compounds from more elementary substances by means of one or more chemical reactions

Define Degradation in Glycogen Synthesis and Degradation

The reduction of a chemical Compound to one less complex, as by splitting off one or more groups

In Glycogenesis glycogen is _______ from glucose

synthesised/made

There are __ steps of Glycogenesis

The starting material in Glycogenesis is g_____ _-p_______

glucose 6-phosphate

Glycogenolysis breakdown of g________ to produce g______-_-p_________

glycogen, Glucose-6-phosphate

Glycogenolysis (breakdown of glycogen to glucose) is activated by _______ when there are _____ blood glucose levels (hypoglycaemia in the liver) or by adrenalin in the muscles.

glucagon, low

There are __ steps of Glycogenolysis

G__________ - breakdown of stored glycogen for the release of glucose. G__________ - the synthesis of glucose from non-carbohydrate sources when there is low glucose available. G___________ - when Glucose is available generates ATP and pyruvates for the generation of ATP. G___________ - when there is excess glucose. Synthesis of glycogen for storage in liver and muscle.

Glycogenolysis (Glyco - gen - ol - o - sis) Gluconeogenesis Glycolysis Glycogenesis

Glycogenesis

The making of glycogen - genesis (comes first)

Glycogenolysis

The breaking down of glycogen - genolysis (longer name comes second to genesis)

Glycolysis

Making pyruvate from glucose - shortest name meas most simple process

Gluconeogenesis

Making glucose from a non-carb source - Glu is different from Gly easy to remember that it makes glucose from non glucose substances

The coenzymes created in the citric acid cycle (CAC), beta oxidation and glycolysis ______ and _____ are required for the electron transport chain. .

NADH and FADH2

Each time our body goes through the CAC, we create _______ NADH and ______ FADH2.

three, one

ETC process Breakdown 1 - Coenzymes _____ and _____ are produced by catabolic process 2 - E_______ and h_____ i____ are carried into the ETC 3 - E_______ are passed along carriers in the ETC 4 - H________ i___ move from the m____ into the i___________ space 5 - P____ m____ f____ (energy obtained from the proton gradient) PMF used to catalyse ATP

ETC process Breakdown 1 - Coenzymes NADH and FADH2 are produced by catabolic process 2 - Electrons and hydrogen ions are carried into the ETC 3 - Electrons are passed along carriers in the ETC 4 - Hydrogen ions move from the matrix into the intermembrane space 5 - Proton motive force (energy obtained from the proton gradient) PMF used to catalyse ATP

The enzymes that act as electron carriers of the ETC are located within the inner mitochondrial membrane as four distinct protein complexes,. They each have a particular role, but are all involved in passing electrons onto the next complex; with their primary role being enzyme carriers. I - NADH-Coenzyme Q Reductase:________________ II - Succinate-Coenzyme Q Reductase: _____________ III - Coenzyme Q-Cytochrome c Reductase: ___________ IV - Cytochrome c Oxidase:____________

I - NADH-Coenzyme Q Reductase: Causes oxidisation of NADH to form NAD+ II - Succinate-Coenzyme Q Reductase: Causes oxidisation of FADH2 to from FAD III - Coenzyme Q-Cytochrome c Reductase: Electrons from I and II pass into III IV - Cytochrome c Oxidase: All electrons passed from III into IV and then to final acceptor, oxygen

The enzymes that act as electron carriers of the ETC are located within the inner mitochondrial membrane as four distinct protein complexes. They each have a particular role, but are all involved in passing electrons onto the next complex; with their primary role being enzyme carriers. I - NADH-Coenzyme Q Reductase:________________ II - Succinate-Coenzyme Q Reductase: _____________ III - Coenzyme Q-Cytochrome c Reductase: ___________ IV - Cytochrome c Oxidase:____________

I - Causes oxidisation of NADH to form NAD+ II - Causes oxidisation of FADH2 to from FAD III - Electrons from I and II pass into III IV - All electrons passed from III into IV and then to final acceptor, oxygen

In the ETC oxygen is the final electron acceptor. Here, ____ is formed when e- (electron) and H+ (hydrogen ions) interact with molecular ____

H2O, O2

Oxidative Phosphorylation (OP) is the process by which ATP is synthesised from ___ and __, using the energy released by the ETC. ADP + Pi + energy (H+ gradient) = ATP

ADP and Pi

Oxidative phosphorylation relies on the ETC to take place, does this make it a coupled reaction?

coupled reaction

For every 2e- (electrosn) passed through the ETC, 10H+ are transferred from the matrix into the intermembrane space, where they will build-up. The increased H+ in the intermembrane space, and the decrease H+ in the matrix creates an e________ (proton) g________.

electrochemical (proton) gradien

Some of the energy gained from the proton gradient is released as _______, with the primary function of increasing b___ t__________. Uncoupling agent thermogenin performs this process often in newborn or hibernating mammals.

heat, body temperature

Each time we complete a citric acid cycle, we create three NADH, one FADH2 and one GTP, which means we will be able to generate __ ATP per cycle. 1. 1 mole of NADH from the CAC produces 2.5 mole ATP in the ETC/OP 2. 1 mole of FADH2 from the CAC produces 1.5 ATP mole in the ETC/OP 3. 1 mole of GTP is an equivalent to 1 mole of ATP

How many ATP is formed in Glucose Metabolism?

Muscle contraction, Nutrient transport and Biosynthesis of essential compounds are all important functions of A___

ATP

The inputs for the ETC are ____ and _____, whereas the output is ___, and the purpose of the ETC is to pump H_______ I___ __ from the matrix into the intermembrane space of the mitochondria

NADH and FADH2, H2O, Hydrogen Ions H+

The function of protein complexes in the ETC is to pass electrons along using r____ r________ which opens up the H+ channels

redox reactions

What would happen to the ETC in the absence of oxygen?

The ETC would stop without oxygen, as the electrons would stay on complex IV preventing more electrons from being passed along the chain

What is the main input and output of OP and what is the purpose of OP?

The inputs for OP are H+ and ADP, whereas the output is many ATP, and the purpose of OP is to produce many ATP to power the cellular processes

Explains why OP is reliant on the ETC?

The ETC complexes pump H+ into the intermembrane space of the mitochondria, where the H+ movement through ATP synthase powers the generation of ATP via OP

How is ATP generated in the process of OP?

The attachment of ADP to a phosphate (Pi) unit is facilitated by the energy from the H+ movement through ATP synthase

Carbohydrate Metabolism Flashcards

(103 cards)