Test 2 Part 1 Flashcards
What is bioenergetics?
Energy associated with biological systems
Release, storage, and use of this energy
How much of diet dry matter is used for energy?
75%
What is energy derived from?
Not a nutrient, so it comes from organic compounds in the diet
What is energy derived mean?
Complete or partial oxidation of organic compounds
Where are the organic compounds from derived energy absorbed?
GI tract
What is the form of energy?
Chemical form
Where is energy stored?
In covalent bonds
When can animals used the energy stored in bonds?
When they break the bonds
What does trapping energy require?
Systematic breaking of bonds and trapping electrons
Where does energy actually come from?
Electrons
What is the systematic breaking of bonds required for?
To produce energy
Where does chemical energy originally come from?
The sun
What is heat?
The most common form of energy in biochemical reactions
What does inefficient metabolism mean?
Body is not 100% efficient because not all ATP energy is used for work.
What happens when heat escapes(given off)?
It allows for optimum body temperature maintenance
What is a calorie?
Unit of heat measured
Amount of heat required to raise the temperature of 1 gram of water 1ºC from 14.5ºC to 15.5ºC at 1 atmospheric pressure
What is gross energy?
Caloric density
Total energy in a compound
How is gross energy measured?
With a bomb calorimeter
What is a bomb calorimeter? (3)
A pure O2 environment that ignites and blows up
Chemical energy is converted to heat
Heat produced is measured and that is the caloric density/gross energy
How many kcal/g is glucose?
3.75
How many kcal/g is CHO?
4
How many kcal/g is protein?
4
How many kcal/g is fat?
9
How many kcal/g is alcohol?
7
What is the 1st law of thermodynamics?
Energy is not created nor destroyed
It can be accounted for somewhere in the animal’s body
What type of energy is unavailable?
Fecal energy, urinary energy, and CH4
What is useful energy used for?
Work
What type of energy is heat?
Available, but not useful
What is heat increment?
How energy is lost
How is digestible energy calculated?
Gross energy – fecal energy
How is metabolizable energy calculated?
Gross energy – fecal energy – urinary energy(–Gaseous Products of Digestion=CH4)
What is metabolizable energy?
Actual energy available to tissues for metabolism
How is net energy calculated?
Gross energy – fecal energy – urinary energy(-GPD=CH4) – heat increment
What is net energy?
Actual energy used for work
Look at chart on page 33
Look at chart on page 33
What 5 things is energy utilized for?
1) Digestion and absorption of organic compounds containing covalent bonds
2) Excretion of energy containing compounds in feces and urine. Energy is not available to animal tissues
3) Metabolism of compounds that breaks the covalent bonds, transfers electrons, and releases energy
4) Trapping of energy as ATP for work
5) Produce heat from inefficient metabolism
Where do we get energy from?
Food
What does the oxidation of food release?
Free energy from chemical bonds
What is energy oxidized to? By what?
CO2 and water via enzymes
What is oxidation?
Loss of electrons from a compound
Leads to an increase in O2 content and a decrease in H content
What is reduction?
Gain of electrons
Leads to an increase in H content and a decrease in O2 content
What does the redox state determine?
Caloric density
If a compound is (more or less) reduced, there is (more or less) caloric density.
More, more
What is the most reduced nutrient?
Fat
What is oxygen?
Terminal electron acceptor in the body
Reduced to H2O
What do electron carriers do?
Transfer electrons in redox reactions (coenzymes)
What is NAD?
Niacin (also NADP)
What is the oxidized version of NAD?
NAD or NADP
What is the reduced version of NAD?
NADH or NADPH
What is FAD?
Riboflavin
What is the oxidized version of FAD?
FAD
What is the reduced version of FAD?
FADH
What are electrons used for when reduced? What is it done through?
Energy–ATP
Electron transport
What is ATP produced as?
A result of oxidation
What does ATP provide?
Energy for muscle (contraction and relaxation)
How many kcals of energy does each phosphate group have?
7.3 kcals
How is energy transferred?
As phosphate bonds
How many kcals of energy does creatine phosphate have?
10.3 kcals
What are the 5 functions of ATP?
1) Muscle contraction
2) Synthesis of new compounds
3) Transmissions of nerve impulses
4) Active absorption in SI
5) Heat production
What happens in synthesis of new compounds?
Amino acids link together to form protein
How many ATP are in a link between amino acids?
4
What does heat production come from?
Oxidation of foods (thermoregulation)
What is intermediary metabolism?
Fate of dietary components after digestion and absorption
Flow of molecules through metabolic pathways and interaction between these pathways
What is the liver?
The primary metabolic organ
What is the function of the liver?
To regulate blood concentration of most metabolites
What is the hepatic portal vein?
Vein that carries absorbed nutrients from GI tract to liver
What are cells in intermediary metabolism?
The level at which metabolic pathways occur
What are 6 types of metabolic pathways?
Glycolysis Gluconeogenesis Lipolysis Krebs cycle β oxidation Electron transport
What are anaerobic processes? Where do they occur?
Oxygen is not present
Cytoplasm
What aerobic processes? Where do they occur?
Oxygen is present
Mitochondria
What is the net reaction for glycolysis?
Glucose + 2 ADP + 2 Pi –> 2 pyruvate + 2 ATP + 2 NADH
Is glycolysis anaerobic or aerobic?
Anaerobic
What is the order of things produced in glycolysis? (11)
Glucose Glucose 6-phosphate Fructose 6-phosphate Fructose 1,6-biphosphate Dihydroxyacetone phosphate and... ...Glyceraldehyde 3-phosphate 1,3-bisphosphoglycerate 3-phosphoglycerate 2-phosphoglycerate Phosphoenolpyruvate Pyruvate
What enzyme and cofactor cause glucose to turn into glucose 6-phosphate? What direction does it go in? Is ATP used or created?
Hexokinase and Magnesium
One direction glucose –> glucose 6-phosphate
ATP used
What enzyme causes glucose 6-phosphate to turn into Fructose 6-phosphate? What direction does it go in? Is ATP used or created?
Phosphohexose isomerase
Both directions
Neither
What enzyme and cofactor causes fructose 6-phosphate to turn into Fructose 1,6-bisphosphate? What direction does it go in? Is ATP used or created?
Phosphofructokinase and magnesium
One direction 6 –> 1,6-
Used
What enzyme causes Fructose 1,6-bisphosphate to turn into dihydroxyacetone phosphate? What direction does it go in? Is ATP used or created?
Aldolase
Both
Neither
What enzyme causes Fructose 1,6-bisphosphate to turn into Glyceraldehyde 3-phosphate? What direction does it go in? Is ATP used or created?
Aldolase
Both
Neither
What enzyme causes dihydroxyacetone phosphate to turn into Glyceraldehyde 3-phosphate? What direction does it go in? Is ATP used or created?
Phosphotriose isomerase
Both
Neither
What enzyme causes Glyceraldehyde 3-phosphate to turn into 1,3-bisphosphoglycerate? What direction does it go in? Is NADH used or created?
Glyceradlehyde-3-phosphate dehydrogenase
Both
Both: Used to make NAD which is used to make NADH + H
What enzyme and cofactor causes 1,3-bisphosphoglycerate to turn into 3-phosphoglycerate? What direction does it go in? Is ATP used or created?
Phosphoglycerate Kinase and Magnesium
Both
Both
What enzyme causes 3-phosphoglycerate to turn into 2-phosphoglycerate? What direction does it go in? Is ATP used or created?
Phosphoglycerate mutase
Both
Neither
What enzyme and cofactor causes 2-phosphoglycerate to turn into phosphoenolpyruvate? What direction does it go in? Is ATP used or created?
Enolase and Magnesium
Both
Neither
What enzyme and cofactor causes phosphoenolpyruvate to turn into pyruvate? What direction does it go in? Is ATP used or created?
Pyruvate kinase and magnesium
One
Created
What is the net reaction for krebs cycle?
2 Pyruvate –> 2 acetyl Co-Aa + 2CO2 + 2 NADH
2 acetyl Co-A –> 4 CO2 + 6 NADH +2FADH2 + 2 ATP
Is krebs cycle aerobic or anaerobic?
Aerobic
What is the order of products in krebs cycle?(8)
Oxaloacetate Citrate Isocitrate α-Ketoglutarate Succinyl-CoA Succinate Fumarate Malate
What enzyme turns Oxaloacetate to citrate? What else is involved? What direction does it go in?
Citrate synthase
Acetyl CoA
One
What comes out of pyruvate at the beginning of krebs cycle? Due to what?
CO2 and NADH
Pyruvate dehydrogenase
What enzyme and cofactor turns citrate to isocitrate? What direction does it go in?
Aconitase and Iron
Both
What enzyme and cofactor turns isocitrate to α-Ketoglutarate? What direction does it go in? Is NAD used or created?
Isocitrate dehydrogenase and Manganese
Both
Both
What enzyme turns α-Ketoglutarate to succinyl-CoA? What direction does it go in? Is NAD used or created?
α-Ketoglutarate dehydrogenae complex
One
Used
What enzyme and cofactor turns succinyl-CoA to succinate? What direction does it go in? Is ATP used or created?
Succinate Thiokinase and magnesium
Both
Both
What enzyme turns succinate to fumarate? What direction does it go in? Is FAD used or created?
Succinate dehydrogenase
Both
Both
What enzyme turns fumarate to malate? What direction does it go in?
Fumarase
Both
What enzyme turns malate to oxaloacetate? What direction does it go in? Is NAD used or created?
Malate dehydrogenase
Both
Both
What is the net reaction for electron transport?
NADH =3 ATP
FADH2 = 2 ATP
Is electron transport aerobic or anaerobic?
Aerobic
Look at page 44
Look at page 44
What is the net reaction overall?
Glucose–> 6CO2 + 2 ATP + 2ATP + 2 NADH + 2FADH2 + 8NADH
How many ATP are produced? How many in reality?
36
40
What are carbohydrates?
Carbon containing compounds that also contain H and O in the same ration as water
Major energy source of the body
What is a monomer? What is a CHO monomer called?
Basic building block
Monosaccharides
What is the major energy source for most cells?
Glucose
What are the 2 types of monosaccharides?
Hexoses and Pentoses
What are the 4 types of hexoses?
Glucose
Fructose
Galactose
Mannose
Draw the structure for glucose, fructose, galactose, and mannose.
Draw the structure for glucose, fructose, galactose, and mannose.
What are the 3 types of pentoses?
Arabinose
Xylose
Ribose
Draw the pentoses
Draw the pentoses
What are the disaccharides? What are they made of?
Sucrose (Glucose, fructose)
Lactose (Galactose, glucose)
Maltose (Glucose, glucose–α 1,4)
Cellobiose (Glucose, glucose–β 1,4)
What are the polysaccharides?
Amylose
Amylopectin
Glycogen
Cellulose
Draw α-Ketoglutarate
Draw α-Ketoglutarate
What is amylose?
Glucose with α 1,4 links
What is amylopectin?
Glucose with α 1,4 links and 1,6 branches
What is glycogen?
Same as amylopectin, but with more branching
What is cellulose?
Glucose with β 1,4 links
