BICH 411 EXAM 1 Flashcards

Fat soluble vitamins are not readily secreted but

What vitamins are fat soluble

If you are lacking vitamins,

Purpose of these elements:

Mg²⁺:

Ca²⁺:

Zn²⁺:

A metabolic pathway is a series of_______reactions, often located in a specific part of the cell.

Without enzymes,

Enzymes provide a way to couple energetically ___________reactions with______.

Catabolic reactions go through_________where it takes electrons and breaks bonds

Degradation breaks_______to_________

Anabolism reactions go through______where_______ turn to _______

What macromolecules are broken down in catabolism?

The end goal of catabolism

_____is the electron carrier produced by glycolysis

Catabolism is____, and anabolism is____

When the energy state of the cell is LOW, we would expect to see reactions taking place with end product such as?

If, in the course of a reaction, NAD⁺ goes to NADH, then the reaction is____

Metabolic pathways are localized within different cellular compartments

What mechanisms occur in the cytosol?

What mechanisms occur in the mitochondrion?

What are the four strategies to control enzymes?

Allosteric control includes substrates, products, and coenzymes of the pathway. This is ______feedback regulation

covalent modification is a

Enzymes that control flux of a pathway have specific sites that can be _______

Covalent modifications are_______ such as hormones

In substrate cycles, the foward reaction is________while the reverse reaction is______

In genetic control, altering the concentration of enzymes can lead to

ATP-->(ADP+Pi) doesn't have the highest free energy because

ATP--->(ADP+Pi) has a free energy charge of_____ and needs______to make more ATP.

Hydrolysis increases _____ and _______

Hydrolysis decreased_____

NAD⁺ and FAD _____electrons

Reduction___electrons

Oxidation___electrons

Electron transfer can be

NADH is a common electron carrier and always transfers_____

what does biosynthesis rely on?

What structure is this?

Mg²⁺interacts with the negative charges on the phosphate group to shield negative charges,

Pentose phosphate pathway is an alternative pathway that allows for____production and provides biosynthetic precursors

GNG is a pathway in the _____and_____ that allows for biosynthesis of glucose from pyruvate, lactate, and amino acids.

Glycolysis and GNG are reciprocally regulated by allosteric effects, _______ and _______

Low affinity transporter in hepatocytes (liver) and pancreatic cells

Higher affinity transporter in adipose tissue and muscle cells

Is driven by concentration and hormones, independent of Na⁺

GLUT2 has about a Km=15mM and captures excess glucose primary for

GLUT2 is considered to be first order kinetics because______.

low affinity=

GLUT4 has about a Km=5mM which means transport is saturated with slightly

GLUT4 is considered to be

After a meal, glucose is____.

Before a meal, glucose is______

high affinity=

A stimulated cell of insulin causes for localization of _______to plasma to boost glucose uptake in cell

Glycolysis occurs in the____ and doesn't require

The products of glycolysis are

The three fates of pyruvate are

Investing ATP allows for glucose uptake to be____.

Utilizing ATP to irreversibly convert glucose to G6P allows for____

G6P is not allowed to cross the plasma membrane due to____

What sugars can hexokinase be used for?

Hexokinase has high affinity, and provides_____

The liver stores extra___ and doesn't compete with other tissues

What sugars can glucokinase be used for?

Due to the poor affinity of glucokinase, it allows for the liver

Glucokinase has a

What substrate is the branch point for several metabolic pathways?

How does hexokinase and glucokinase prevent ATP from reacting with water?

What intermediate is formed when making G6P to F6P?

In phosphofructokinase, a decrease in ATP and an increase in AMP causes for

The R-state(high affinity) of PFK allows for the _____

The T-state(low-affinity) of PFK allows for the_____

Positive allosteric effectors shift equilibrium to favor

Negative allosteric effectors shift equilibrium to favor

PFK is first

PFK activity_____ when the energy status of cell is low, and _____-when the energy status is high.

Is PFK tightly regulated?

F-2,6-BP stimulates PFK by decreasing

In aldolase, each end is phosphorylated before

What does the aldolase enzyme found in animal tissues form into?

What does the aldolase enzyme found in bacterial and fungi form into?

Which carbon in glucose becomes C=O in DHAP after both aldolase and triose P isomerase?

TPI is a near perfect enzyme because it has

In glycolysis first phase, ___ATPs are consumed. In the second phase,____ATPs are produced. Which results in a net ATP yield of __ATPs per glucose.

Glyceraldehyde 3-phosphate dehydrogenase uses_______ as a cosubstrate which involves the exchange of electrons.

Gly-3P is oxidized to

Phosphoglycerate kinase transfers a phosphoryl group from 1,3-bisphosphoglycerate to ADP to ATP

A___is an enzyme that catalyzes the migration of a function group within the substrate molecule

The enolase reaction in glycolysis is a

Pyruvate Kinase irreversible in vivo

ATP production via glycolysis doesn't require____

What are the key regulatory steps (irreversible)?

Flexible loop closes over TIM active site and creates

What other substrates can be used for glycolysis?

Fructose (muscle) requires____

A tagged glucose (UDP) must occur to

What enzymes are needed for galactose to go through glycolysis?

What enzymes are needed for mannose to go through glycolysis?

What enzyme is needed for fructose to go through glycolysis in the muscle?

What enzymes are needed for fructose to go through glycolysis in the liver?

Activators:

Inhibitors:

Important regulation steps in glycolysis in liver

Fructose only metabolizes in excess amounts by_____ and excess sugar become____

Glycerol is produced in the decomposition of____.

In the ethanol endpoint of glycolysis, is a 2 step process catalyzed by

In the lactate endpoint of glycolysis, pyruvate is reduced by _____ and is reversible

Aerobic glycolysis generates more ATP but has a ______

Anaerobic glycolysis generates less ATP but has a

What is the Cori cycle?

What type of twitch muscles do these characteristic represent?

-dark in color

-has endurance

-is aerobic

What type of twitch muscles do these characteristic represent?

-is anaerobic

-light in color

-fatigues easily

Humans do not have_____, but they do have_____

Humans do not have pyruvate carboxylase, but they do use______

Does TPP allow for a better reaction pathway?

Mechanism of pyruvate decarboxylase

The body has enough glucose to supply for one day, so it must be made from

The brain functions on glucose and accounts for 75% of

Muscles also require______

GNG meets the body's glucose needs under_____

Our brains cease to function when blood glucose concentration is_____

Humans consume about___per day

The reactions that goes from pyruvate to TCA, occur in the

Body fluids contain only ___ of glucose.

Glycogen stores yield____of glucose.

What are the substrates for GNG?

Acetyl-CoA cannot provide for

GNG has four different enzymes from glycolysis because

Acetyl CoA is a main carbon source for TCA cycle where an increase in acetyl-coA means

Biotin is a vitamin that serves as a

Pyruvate carboxylase uses ATP to load CO₂ onto ____then delivers it to ______

PEP carboxykinase uses

Why does cell add CO₂ with pyruvate carboxylase and then take it back off with PEPCK?

Fructose-1,6-bisphosphatase allosteric regulation:

F1,6BPase: What gets inhibited vs. activated?

PFK1: What gets inhibited vs. activated?

PFK-2 domain

F2,6BPase domain

the presence of G-6-Pase in ER of the ____and______ cells makes GNG possible

Muscles and brains DO NOT do______

Glucose-6-phosphatase reaction involves_____by a histidine nitrogen and formation of a_________

Vigorous exercise lead to the build up of__________due to O₂ shortage and the need for more glycolysis

NADH is reoxidized during the reduction of

Lactate is then reduced to the liver where it can be reoxidized to

GNG is driven by the consumption of___-

When glycolysis is turned on, GNG should be

When cell's energy status is high, glycolysis should be off and should be used for

When cells energy status is low, glucose should be rapidly

An individual is sprinting, what type of regulation is going on in terms of glycolysis and GNG?

IN THE MUSCLE

An individual is sprinting, what type of regulation is going on in terms of glycolysis and GNG?

IN THE LIVER

Pentose phosphate pathway has 2 phases:

The oxidative phase of PPP uses glucose metabolism to

The nonoxidative phase of PPP uses glucose metabolism to supply

The first 4 substrates makes

The bottom substrates interconvert

NADH is mainly in______form and removes 2e^- during fuel metabolism

NADPH is mainly in _______form and adds 2e^- during biosynthesis and detox of free radicals

PPP operates mostly in

G6P dehydrogenase is regulated by NADPH levels

-NADPH is a _____, cytosolic levels of NADP⁺/NADPH dictate enzymes activity

Hyrdolysis of lactone occurs both

6-phosphoglucono8-lactone is hydrolytically unstable, so it readily undergoes

reaction 2: gluconolatonase accelerates the spont. ring opening hydrolysis in order to

The 2 phases of oxidative decarboxylation:

Phosphopentose isomerase has an

Ribose-5-phosphate is used in biosynthesis of

Phosphopentose Epimerase change in position of acidic proton and has a

Transketolase is the transfer of _____ from ketose(donor) to aldose(acceptor) and utilizes _____

Although reaction is called transketolase, the group that is transferred is a_____

Transaldolase converts ___skeleton to a useful______skeleton, and it transfers_____

The transaldolase mechanism involves attack on the substrate by

The nonoxidative steps consists of

What does phosphopentose isomerase do?

What does phosphopentose epimerase do?

What does transketolase(TPP-dependent) do?

What does transaldolase do?

What are the 5 variations of PPP?

1) More ribose-5-P than NADPH is needed

What types of situations would call for this?

3) more NADPH than ribose-5-P is needed:

when fatty acids are being synthesized,

4) NADPH and ATP are needed, but ribose-5-P is not

Generate intermediates for glycolysis,

More than likely the goal will be_____ in PPP

Is a multi-branched polysaccharide of glucose

What is glycogen used for?

Glycogen is the readily mobilized storage form of_____

The liver has higher concentrations of glycogen stored due to controlling

______is where most of the glycogen is stored

The muscle consists of_____glycogen, triggers fight or flight, and quickly mobilized

The liver is up to______glycogen.

the liver must maintain about ______blood glucose.

The liver also has a 12 hour supply of_____

Glycogen has_____and linkages

Amylase is a saliva enzyme that hydrolysis the alpha(1->4) glycosidic bond of_____

An enzyme that hydrolysis one glucose residue at a time and is capable of alpha(1->6) glycosidic bonds and leaves glycogen with one less point

An enzyme that transfers trisaccharide unit and converts it to a alpha(1->4) bond

α-amylase is found in_____ and β-amylase is found in____

Endoglycosidase hydrolysis α(1->4) linkages which produces a

Starch digestion is highly efficient and almost 100% of digested food is____ and ____-

How is degradation achieved?

Glycogen degradation in muscles and liver indicate important energy reservoirs stored in the

Allows for the breakdown of glycogen into glucose1-P

Glycogen phosphorylase is activated by:

Glycogen phosphorylase:

ATP and glucose-6-phosphate is a________

Glycogen phosphorylase:

The response to the concentration of the substrate_____-

Glycogen phosphorylase:

____is a positive effector that binds at the same site as ATP

T-state is stabilized by____ and ________.

(high ATP signals no need for energy)

R-state: stabilized by______.

(low ATP signals a need for energy)

The breakdown of a molecule directly using phosphate

What type of reaction is this?

Glucose units are activated for transfer by formation of sugar nucleotides

What are other examples of activation?

Glycogenin is a protein that

In glycogen synthase, what gets kicked off?

Glycogen synthase is allosterically regulated by:

increase in G6P, when G6P is high,

Glycogen synthase is less active in the______form and more active in the______form

90% of glycogen cleaved into G1P which is

10% are the branched residues that are hydrolyzed into glucose can than be

The complete oxidation of G6Pvia glycolysis, TCA cycle and oxidative phosphorylation yields 38 molecules of ATP which means its effciency of storage is

what are the 3 fates of G6P?

Glucose-1-phosphate cannot escape the cell because

Why galactose and glycogen metabolism involve UDP?

If O₂ levels are reestablished in the muscle,

What are the three important hormones?

What is the allosteric regulation for glycogen synthase?

What is the allosteric regulation for glycogen phosphorylase?

If there is excess sugar and energy, there is an increase in G6P, ATP, and a decrease in AMP. This result in

If there is low sugar but a energy demand, there is a decrease of G6P, ATP, and an increase in AMP. This cause the

Insulin (high blood sugar) cAMP________ and stores glycogen and fat

Epinephrine(adrenalin)_______cAMP and give fight or flight signals as well as mobilizing glycogen

Glucagon(low blood sugar) cAMP is ______ in the ______, and it mobilizes liver glycogen and sends glucose to brain

Insulin is secreted as a response to

Is a peptide hormone produced from beta-cells in the pancreas

The body utilizes different pathways that use glucose to

When lots of glucose is about to be needed, what can aid in producing it?

Where is glucagon released from?

Where is epinephrine released from?

Glucagon and epinephrine inhibit glycogen synthase and activate

The end goal of hormone -activated enzymatic cascade has an end goal of

What structure is this?

Epinephrine activates glycogen_____ and inhibits glycogen_______.

Glucogen stimulates liver to release glucose from

Exercise--> low blood glucose->

exercise requires lots of

Glucagon specifically targets the

Low blood sugar-->glucagon secreted by pancreas-->

Liver's response to LBG:

1. LBG
2. Increased glucagon secreation
3. increased cAMP
4. increased enzyme phosphorylation
5. ?
6. ?
7. ?
8. ?

Excess food+ no exercise-->

Some glucose will be retained as glycogen but only 1-2% is stored, the rest must be dealt by the