Anaerobic & Aerobic Respiration Flashcards
what is the structure of mitochondria
what is the difference between nuclear vs mitochondrial DNA
circular, double stranded
extracellular source of DNA
encodes 37 proteins
nuclear DNA is inherited from all ancestors, mito is inherited from sinle lineage
how are substances transported into the mitochondria
- outer MM: porins allow passive diffusion of small proteins (CO2, O2, etc)
- translocases –> larger proteins need to be transported
TOM: translocator outer membrane
TIML translocator inner membrane
how is mitochondrial fission and fusion
fission: increase in mitochondrial number –> splits
fusion: increase in mitochondrial mass –> fused
how are mitochondria highly dynamic
cellular migration, fusion, fission, turnover
respond to energetic requirements
exercise, hypoxia
what occurs in exercise training and mitochondria
- mitochondrial density increased
- number of capillaries increased
- diffusion index decreased
what is the primary function of mitochondria
generate ATP
what is the net production of ATP per glucose
38 mol ATP/glucose
how many ATP does glycolysis produce
glucose –> 2 pyruvates
+2 ATP
+2 NADH
how many ATP does krebs cycle
+2 ATP
+6 NADH
+2 FADH2
how many ATP does ETC
+34 ATP
what is glycolysis
substrate level phosphorylation
where does gylcolysis occur
cytoplasm
does glycolysis require oxygen
no
what is anaerobic metabolism
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
what is lactic acidosis and what causes it
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
what is ethylene glycocol and how does it cause metabolic acidosis and how is it treated
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)
what is pyruvate dehydrogenase complex
converts pyruvate to acetly coA
vitamin B1 (thiamine) needed –> thiamine pyrophosphate (TPP)
thiamine deficiency –> anorexia, cardiac hypertrophy
what is the krebs/citric acid cycle
pyruvate metabolized to acetly coA –> oxidized in krebs cycle
high energy electron donors –> NADH, FADH2, ETS
what is ATP
adenosine triphosphate
highly unstable
ADP + Pi ——-> ATP + H2O
converted by ATP synthase
ATP hydrolized to ADP + Pi
what is ATP synthase
energy powers proton motive force –> protons to intermembrane space –> generates electrical voltage across IMM
last complex in the ETC
what is shivering thermogenesis
primary motor centre –> activation of antagonistic muscles (contraction but little movement) –> metabolically expensive & inefficient
what is non-shivering thermogenesis
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
what role does UCP1 play in NST
makes membrane more permeable –> protons pass thru and bypass ATP synthase –> produces heat in brown adipose tissues
release heat
how do animals hibernate
abandon euthermia in response to cold/food shortages
reliant on food caches/body reserves over weeks/months
how do animals prepare for hibernation
increase brown fat depots and UCP1 levels
how do neonates use NST
at birth –> profound thermolysis
peri/post natal catecholamine surge –> NE, E, dopamine
increased fatty acid levels via hormone sensitive lipase, increase NST
what is the role of NST and obesity
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
how do piglets stay warm
lack UCP1 protein –> neonatal hypothermia
UCP-3, SERCA thermogenesis
what is the role of mitochondria in ageing
produces ROS –> oxidative damage –> functional decline –> ageing
what diseases are linked with mitochondria
inherited parkinson’s
hypertension
some cancers
alzheimer’s
beta-amyloid localizes to mitochondria
what are inherited metabolic disease
inborn errors of metabolism
archibald garrod –> mendelian inheritance to phenotypic variation and metabolism –> classic failure to thrive phenotype
what is faconi syndrome
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
what is metabolic intoxication
malignant hyperthermia –> inherited mutation on ryanodine receptor
stress, exercise, heat, volatile anaesthetics
what is sensory ataxic neuropathy
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
