Anaerobic & Aerobic Respiration

Question 1

what is the structure of mitochondria

Answer 1

Question 2

what is the difference between nuclear vs mitochondrial DNA

Answer 2

circular, double stranded

extracellular source of DNA

encodes 37 proteins

nuclear DNA is inherited from all ancestors, mito is inherited from sinle lineage

Question 3

how are substances transported into the mitochondria

Answer 3

1. outer MM: porins allow passive diffusion of small proteins (CO2, O2, etc)
2. translocases –> larger proteins need to be transported

TOM: translocator outer membrane

TIML translocator inner membrane

Question 4

how is mitochondrial fission and fusion

Answer 4

fission: increase in mitochondrial number –> splits
fusion: increase in mitochondrial mass –> fused

Question 5

how are mitochondria highly dynamic

Answer 5

cellular migration, fusion, fission, turnover

respond to energetic requirements

exercise, hypoxia

Question 6

what occurs in exercise training and mitochondria

Answer 6

1. mitochondrial density increased
2. number of capillaries increased
3. diffusion index decreased

Question 7

what is the primary function of mitochondria

Answer 7

generate ATP

Question 8

what is the net production of ATP per glucose

Answer 8

38 mol ATP/glucose

Question 9

how many ATP does glycolysis produce

Answer 9

glucose –> 2 pyruvates

+2 ATP

+2 NADH

Question 10

how many ATP does krebs cycle

Answer 10

+2 ATP

+6 NADH

+2 FADH2

Question 11

how many ATP does ETC

Answer 11

+34 ATP

Question 12

what is glycolysis

Answer 12

substrate level phosphorylation

Question 13

where does gylcolysis occur

Answer 13

cytoplasm

Question 14

does glycolysis require oxygen

Answer 14

no

Question 15

what is anaerobic metabolism

Answer 15

reduction of pyruvate to lactate

more rapid than aerobic metabolism

fight or flight –> can’t maintain high levels of lactate, only short periods of time –> muscle damage

Question 16

what is lactic acidosis and what causes it

Answer 16

build up of L-lactate in blood leading to excessively low pH

issue with oxidative metabolism

mitochondrial disease, sepsis, shock, cyanide poisoning, heart failure, propofol, CKD, excessive exercise, high grain diet in ruminants

Question 17

what is ethylene glycocol and how does it cause metabolic acidosis and how is it treated

Answer 17

sweet tasting

toxic if even feet/coat contaminated

toxic metabolites: glycolic acid (acidosis), oxalic acid, calcium oxalate crystals (renal failure)

treatment –> ethanol or 4-MP (fomepizole)

Question 18

what is pyruvate dehydrogenase complex

Answer 18

converts pyruvate to acetly coA

vitamin B1 (thiamine) needed –> thiamine pyrophosphate (TPP)

thiamine deficiency –> anorexia, cardiac hypertrophy

Question 19

what is the krebs/citric acid cycle

Answer 19

pyruvate metabolized to acetly coA –> oxidized in krebs cycle

high energy electron donors –> NADH, FADH2, ETS

Question 20

what is ATP

Answer 20

adenosine triphosphate

highly unstable

ADP + Pi ——-> ATP + H2O

converted by ATP synthase

ATP hydrolized to ADP + Pi

Question 21

what is ATP synthase

Answer 21

energy powers proton motive force –> protons to intermembrane space –> generates electrical voltage across IMM

last complex in the ETC

Question 22

what is shivering thermogenesis

Answer 22

primary motor centre –> activation of antagonistic muscles (contraction but little movement) –> metabolically expensive & inefficient

Question 23

what is non-shivering thermogenesis

Answer 23

cold is sensed by brain –> sympathetic nerves are activated –> NE –> brown adipocyte –> cAMP –> protein kinase A –>

acute effects: stimulation of lipolysis, activation of UCP-1 activity

chronic effects: UCP-1 gene transcription, mitochondrial biogenesis, hyperplasia of brown adipose tissue, recruitment of brown adipocyte in white adipose tissue depots

Question 24

what role does UCP1 play in NST

Answer 24

makes membrane more permeable –> protons pass thru and bypass ATP synthase –> produces heat in brown adipose tissues

release heat

Question 25

how do animals hibernate

Answer 25

abandon euthermia in response to cold/food shortages reliant on food caches/body reserves over weeks/months

Question 26

how do animals prepare for hibernation

Answer 26

increase brown fat depots and UCP1 levels

Question 27

how do neonates use NST

Answer 27

at birth --\> profound thermolysis peri/post natal catecholamine surge --\> NE, E, dopamine increased fatty acid levels via hormone sensitive lipase, increase NST

Question 28

what is the role of NST and obesity

Answer 28

chronic treatment with B3-AR agonist results in thermogenic and anti-obestity properties (reduction of BW and girth) stimulates metabolic rate, appearance of BAT deposits

Question 29

how do piglets stay warm

Answer 29

lack UCP1 protein --\> neonatal hypothermia UCP-3, SERCA thermogenesis

Question 30

what is the role of mitochondria in ageing

Answer 30

produces ROS --\> oxidative damage --\> functional decline --\> ageing

Question 31

what diseases are linked with mitochondria

Answer 31

inherited parkinson's hypertension some cancers alzheimer's beta-amyloid localizes to mitochondria

Question 32

what are inherited metabolic disease

Answer 32

inborn errors of metabolism archibald garrod --\> mendelian inheritance to phenotypic variation and metabolism --\> classic failure to thrive phenotype

Question 33

what is faconi syndrome

Answer 33

disorder of proximal kidney tubule urinary loss of electrolytes and nutrients --\> growth retardation, diarrhea, hypokalemia, hyponatraemia, hypochloremia one is inherited form is mutation in EHHADH --\> encodes enzyme involved in fatty acid oxidation impairs mitochondrial metabolism and functionality of proximal kidney tubule

Question 34

what is metabolic intoxication

Answer 34

malignant hyperthermia --\> inherited mutation on ryanodine receptor stress, exercise, heat, volatile anaesthetics

Question 35

what is sensory ataxic neuropathy

Answer 35

mutation in mitochondrial gene clinically presents between 2-8 months of age lack of muscle coordination, abnormal gait, lack of stregnth/balance in hind limbs