Metabolism review Flashcards
What is metabolism
Sum of all biochemical reaction in the body
All occur in cells, catalyzed by enzymes
Both anabolic (join together) and catabolic (Break apart)
what does anabolic mean
join together
what does catabolic mean
break apart
Energy released from catabolism…. can be used to make
ATP from ADP
explain the metabolism circle
1) Macromolecules (polymers- Proteins, complex carb, triglycerides)
2) Catabolic rxn.
- Hydrolysis of large molecules ( Releases energy)
3) Small molecules (monomers - amino acids, monosaccharides, fatty acids)
4) Anabolic reactions
- build large molecules (stores energy in new chemical bonds)
* **just keeps going & going
what type of reaction stores energy
anabolic
what type of reaction released energy
catabolic
Define catabolic reaction & what kind of molecule does it act on
Hydrolysis of lrg molecules that releases energy.
Such as Proteins, Complex carbs, Triglycerides
Define anabolic reaction & what kind of molecules does it act on
Builds large molecules (Stores energy in new chemical bonds)
Such as amino acids, monosaccharides, fatty acids (monomers basically)
What is Adrenosinetriphosphate
The energy currency of cells
Energy in phosphate bonds of ATP can be used directly to fuel metabolic reactions.
What is the energy released when the phosphate bond is broken
34kJ
what is basal metabolic rate
energy required for body to perform all essential processes
***DOESNT include energy expended by activity
what are essential processes
growth, maintenance, heat, nutrition storage, secretion, transport
what is basal metabolic rate affected by
age, sex, body composition, body shape/surface area, hormones (esp. thyroid), stress, environmental temperature
what are metabolic reserves
energy stored in the human body
85% is stored as triglycerides
14.5% is stored as skeletal muscle
0.5% is stored as glycogen/blood glucose
how do most cells generate ATP
by metabolizing carbohydrates
What is the most readily available for carbohydrate metabolism
Glycogen
What is glycogen
a polymer of glucose
Where is glycogen stored?
liver & Muscle (it’s the carbohydrate storage in these places)
how long can glycogen fuel your body
about 90 mins of intense exercise
What is glycogenesis
1) Part of glycogen metabolism
2) Anabolic process
3) Making glycogen from glucose in the liver & muscle]
Glucose -> glycogen
what is glycogenolysis
1) Part of glycogen metabolism
2) Catabolic
3) Breaking down glycogen to form glucose
Glycogen -> glucose
What do you use when ur out of glycogen
Glucose (C6H12O6)
What happens to glucose
cellular respiration
What is cellular respiration
Catabolism of glucose -> energy used to make ATP
can be aerobic or anaerobic
What is aerobic cellular respiration
catabolism of glucose with oxygen
where do most steps of aerobic cellular respiration take place
Mitochondria.
the catabolism of one glucose molecules yields ____ ATP
36-38
what are the products of aerobic cellular respiration
Co2 & H20
White out cellular respiration equation
C6H12O6 + 6O2 -> 6CO2 + H2)
What are the 3 main steps of Aerobic cellular respiration
1) Glycolysis
2) Citric acid/krebs cycle
3) Electron transport & chemiosomsis
what happens in glycolysis
- Sugar splitting!
- Anaerobic step (No O2 required)
- glucose split into 2 pyruvate
- enough energy is released to make 2ATP
- Catabolic, releases energy
where does glycolysis take place
cytoplasm
how many carbons does each pyruvate have
3
what happens to the pyruvate made in glycolysis
It’s transported into mitochondria
what is the net outcome of glycolysis
2ATP & 2 NADH
4 ATP are made by 2 are used some energy is stored in molecules called NADH
where does the krebs cycle take place
the matrix of the mitochondria
What happens to pyruvate in krebs cycle
It is broke down, Carbon is released as CO2.
Then acetylCOA transported it into the krebs cycle
What does NAD stand for & do
Nicotinamide denier dinucleotide
Picks up hydrogens/ electrons during various processes of cellular respiration via reduction reaction.
Manufacture day B vitamins.
what does FAD stand for and do
Flavin Adenin dinucleotide
Picks up hydrogens/ electrons during various processes of cellular respiration via reduction reaction.
Becomes FADH2. Manufactured by B vitamins
why must each glucose go through krebs cycle twice
b/c there a 2 pyruvate
what energy does the krebs cycle net per glucose
2ATP. Some NADH & FADH (energy is stored in the chemical bonds of these compounds
(3Carbons leaves in the form of CO2 )
What is the pruspose of the electron transport & chemiosmosis step
Get energy out of bonds in NADH & FADH2
what happens to hydrogens in the electron transport & chemiosomosis stage
Hydrogens are transferred from NADH & FADH2 to a series of acceptors
where are the acceptors in electron transport & chemiosmosis
Inner membrane/ crystal of mitochondria called the CYTOCHROME OXIDASE SYSTEM
What is the terminal acceptor in oxydase electron chain transport
Oxygen because it’s an aerobic metabolism process.
Oxygen picks up the electrons & protons & Forms H20
how much ATP does electron transport & chemiosmosis net
34 ATP by the process of chemiosismosis using a proton powered enzyme called ATP SYNTHASE
what is a hydrogen atom
1 electron and 1 proton
How is energy released in Electron transport & chemiosmosis and what is it used for
E- are passed from 1 acceptor to another in the cytochrome oxidase system -> energy is released
this energy used to actively transport H+ into intermembranouse space & creates the proton gradient
***H+ is then moved back into the matrix, down it’s concentration gradient through a transport protein called ATP SYNTHASE which is also an ATP synthesizing enzyme
what does ATP synthase do
Moves H+ back into the matrix down it’s concentration gradient. It is a transport protein & an ATP synthesizing enzyme. H+ is then combined with the electron & the terminal accepted O2 to great h20.
What is chemiosmosis
the movement of ions across membrane, down conc. graitent that generates ATP. This is what the ATP synthase does.
Overview of glycolysis
- +2 ATP
- Anerobic
- in cytoplasm
net of krebs cycle
2 atp
net of electron transport chain & chemisosmosis
34ATP
explain aerobic cellular respiration
- Catabolism of glucose without oxygen
- No Co2 or H20 Produced
- glycolysis only.
- Yeilds only 2 ATP per glucose
- produces lactic acid
What does aerobic respiration produce
lactic acid from pyruvate.
Is anaerobic very effective?
no it’s ineffective.
Rapidly depletes glucose/glycogen stores
Why do almost all living creatures need O2
Necessary terminal acceptor for electron transport & effective oxidation of glucose
What happens when glucose & glycogen stores are used up
Gluconeogenesis
What is gluconeogenesis
making glucose from non-carbs IN THE LIVER.
why does gluconeogenesis need to occur?
Most cells can just metabolize fatty acids or amino acids for energy if glucose is gone.
BUT the brain is very reliant of glucose
What things can the liver use to proceed glucose
Gluconeogenesis
Glycerol from fatty acids
amino acids & lactic acid
What is proteogenesis
- anabolic, making proteins.
- amino acids into proteins
where does proteogenesis occur
liver & muscle tissue
what is ketoacidosis
can happen from excessive protein metabolism
what is proteolysis
- Catabolic
- Breaking proteins down.
- Proteins -> amino acids
- Aminos can be used for energy by they must be MODIFIED
how are amino acids modified so that they can be used for energy
Deamination: Removal or amino (NH2) group from an acid.
The amino group is removed & converted into urea & excreted in urine.
The ketoacid is the deaminated part.
what can a ketoacid do to be used as energy
it can be converted into pyruvate
What is transamination
Transfer of amino group from one amino acid to a ketoacid to produce a different amino acid that can be metabolized for energy or used to make a protein.
why is transamination necessary
because only some amino acids can be directly metabolized for energy
Why is lipolysis
- Catabolic
- Breakdown of stored cat (Triglycerides)
- Glycerol converted into pyruvate and Fatty acids converted into acetyl-coa -> this is called beta oxidation.
what can glycerol be converted into
pyruvate
what can fatty acids be converted into
acetyl-coa
beta oxidation of fatty acids produces…
ketones which are organic acids
If carbs aren’t available as fuel (Diabetes, starvation, low carb diets) …
an accumulation of toxic/acidic metabolites (ketoacidosis) occur
what is lipogenesis
- Anabolic
- Triglyceride synthesis from protein + Carb
- Glucose into glycerol
- Amino acids into fatty acid
when does lipogenesis occur
when dietary intake of nutrients exceeds what is required. You’ll store triglycerides in adipocytes
Explain cholesterol metabolism/synthesis
<15% cholesterol from dietary source
<85% synthesized from fatty acids in liver
-Eating dietary saturated fatty acids, increases cholesterol synthesis
What is the absorptive state
after eating -lasts several hours
- anabolic reactions prevail & thus there is storage.
1) After eating blood glucose increases
2) Pancreas secretes insulin
3) The insulin effects the liver, muscles & adipose
4) In the liver, the insulin triggers: Glycogenesis, Proteogenesis & lipogenesis
5) In the adipose it triggers lipogenesis
6) In the muscles it triggers proteogenesis & glycogenesis
What is the post-absorptive state
the fasted state where nutrients aren’t being absorbed
1) Fasted state causes blood glucose to decrease a lot
2) This causes effects on the adrenal cortex, adrenal medulla, and pancreas
3) The pancreas secretes glucagon which triggers glycogeneolysis in liver & muscle cells
4) The adrenal medulla secreted epinephrine
5) The adrenal cortex secretes cortisol
6) The cortisol causes lipolysis in adipose, Proteolysis in liver & muscle & gluconeogenesis in the liver
what is glucose sparring
blood glucose is saved for the brain.
Brain can also use ketones for energy.
