Energy

Question 1

How do you measure energy?

Answer 1

-by calorimetry
-measurement of heat production

Question 2

Who were the OG of calorimetry?

Answer 2

-Lavoisier
-Lapalce

Question 3

What was the experiment that Lavoisier and Lapalce did?

Answer 3

-put guinea pig in a chamber
-measured using melting ice
-related heat production to respiration
-measured water that dripped off ice; proportional to guinea pig

Question 4

What did Lavoisier discover?

Answer 4

-one of the discoverers of oxygen and proved the idea that animals combust food

Question 5

What did the calorimeter and guinea pig demonstrate?

Answer 5

-That the guinea pig and fire both produced same heat per amount of CO2

Question 6

What was the same as heat produced when an animal metabolized a substance?

Answer 6

-heat produced when it was burn

Question 7

What is heat?

Answer 7

Energy

Question 8

What are the laws of thermodynamics?

Answer 8

-First law: energy is neither created nor destroyed (it is transformed). Always the same
-Second law: Energy in its simplest form can be measured as heat

Question 9

What are the laws of thermodynamics for animal nutrition?

Answer 9

-First law: energy input must equal output plus or minus any change in body energy
-Second law: No transformation of energy is 100% efficient and the inefficiencies are lost as heat

Question 10

What is metabolism?

Answer 10

Where energy comes from

Question 11

What do we use energy for?

Answer 11

-Energy for function
-the energy currency of the cell is ATP

Question 12

How is energy used in functions?

Answer 12

-peptide bods: joining acids to make protein
-De novo fat synthesis: synthesizing fatty acids
-Transport of nutrients: as we saw w/ some instances of absorption like amino acids
-cell Maintenace

Question 13

How is energy used in the currency of the cell?

Answer 13

-Cells use ATP to carry out these functions

Question 14

Where does energy come from?

Answer 14

-Energy production
-energy from energy containing nutrients
-energy containing nutrients from feed/food

Question 15

Where do cells derive ATP from?

Answer 15

-glycolysis: energy from glucose
-beta-oxidation: energy from fatty acids
-TCA cycle: further energy from metabolites of glucose and fatty acids (and amino acids)
-Oxidative phosphorylation: energy from final derivatives

Question 16

How do feeds provide energy from nutrients?

Answer 16

-chemical energy is stored in feed nutrients
-cells convert the energy in nutrients to ATP
-ATP is used for cell functions

Question 17

What are the acetyl-CoA inputs of the citric acid cycle?

Answer 17

-from pyruvate
-from ruminal produced acetate
-from acetyl-CoA from fatty acid beta-oxidation

Question 18

What is produced from the two carbons of acetate attached to CoA?

Answer 18

CO2

Question 19

Where does the citric acid cycle occur?

Answer 19

mitochondria

Question 20

What are the outputs of the TCA cycle for each acetyl-CoA?

Answer 20

-3 NADH + H+
-1 FADH2
-1 FADH2
-1 GTP

Question 21

Where does NADH, FADH2, and GTP go?

Answer 21

-NADH and FADH2 go to the electron transport chain
-GTP is readily convert to ATP

Question 22

How does the electron transport chain work?

Answer 22

-NADH + H+ FADH2 transfer their electrons to the electron transport chain and then to electron acceptors like oxygen
-proceeding through the chain releases energy to pump protons (H+) creating an electrochemical gradient
-ways to move electrons out

Question 23

What is oxidative phosphorylation?

Answer 23

-production of ATP via the proton gradient
-ATP synthetase uses the proton gradient energy to convert ADP and Pi to ATP
-ADP to ATP using H ions

Question 24

What is the net energy system?

Answer 24

-keep tracking of the use and usefulness of feed energy

Question 25

Can we account for all energy?

Answer 25

Yes, bc energy is not created or destroyed

Question 26

What does the net energy system account for?

Answer 26

-The net energy system accounts for all the energy btw a feed and use in an animal

Question 27

What are the 4 components of the net energy system?

Answer 27

1. Gross energy
2. Digestive energy
3. Metabolize energy
4. Net energy

Question 28

What happens at each level in the net energy system?

Answer 28

-at each level we reduce how much energy

Question 29

How do we report energy?

Answer 29

Calories or Joules

Question 30

What is a calorie?

Answer 30

-the energy needed to raise the temperature of 1 gram of water through 1 C

Question 31

What does 1 calorie equal?

Answer 31

-heat to raise 1 gram H2O from 14.5 C to 15.5 C