Bio Biochem Flashcards
Liver 4 functions
- detox– cyt P450 oxidizes stuff
- glucose regulation
- bile
- cholesterol metabolism / FA synth
Lipoprotein lipase
releases fatty acids from VLDL’s and chylomicrons in well fed state
-in adipocytes
glycerol phosphate
- in glycolysis
- in TAG synthesis
- when well-fed
- in adipocytes
When starving, hormone-sensitive lipase (low insulin)
Source of fuel
In well-fed:
- cardiac always uses FA
- liver can also use proteins
- everything except heart uses glucose (failing heart uses glucose)
In starvation:
- always fat except brain and RBC must use glucose
- ketone bodies for skeletal muscle and brain
Respirometry
measure respiratory quotient expt’ally
RQ = CO2 produced/O2 consumed
Carbs = 1, Lipids = 0.7 (carbs make more CO2 than lipids per oxygen)
resting = 0.8, we use both simultaneously
Basal metabolic rate
- Calorimeters can measure this using heat exchange
- based on age, weight, height, sex
Body mass protein/carbs same over time, water short term fluctuations, lipids long term
Food hormones
- ghrelin- secreted before meal, increases appetite
- orexin further increases appetite (release triggered by ghrelin and hypoglycemia)
- leptin is secreted by fat- satiety- suppress orexin production
Aluminum in blood- what form?
Al(OH)3 -poorly soluble
in acidic conditions, form Al 3+ and water (solvate), which replaces cofactors in the body and causes harm
(replace Fe3+, Fe2+, Ca2+, Mg2+)
Phosphate in Kidneys- secreted/absorbed where?
PCT and DCT
Proteins not found in urine but removed from the blood…
must have been destroyed (lysosome) or heavily modified (Golgi)
Cell-connections
Hemidesmosomes: skin (attach to ECM)
Desmosomes: attach to adjacent cells exposed to mechanical stress; strong attachment; stomach, heart, bladder
Plasmodesmata: plants, algae
Gap junctions: Kind of everywhere
Tight junctions: Kidney (PCT, DCT, CD), BBB, Part of bile duct traversing liver
Kidney
PCT- most reabsorption, non-ionic secretion
DCT, CD- concentrate urine
DCT- also ion conc, acid/base balance
LoH- Vasa recta exchange, adjust urine [solute]
Respiratory cilia
- mucus elevator- clears pathogens, prevents obstruction of hardened mucus as in COPD
- nonmotile cilia help w/ cough reflex
- no cilia in alveoli
Blood vessel production
angiopoietin + VEGF (platelet-derived)
Ectoderm, Mesoderm
Ecto- Nervous system including axons
Meso- Blood, smooth muscles, endothelial cells, arteries
Capillaries
do NOT have muscle contraction
- primary site of gas exchange
- endothelial turnover when injury/age
- low pressure flow
Heterozygous advantage
- sickle cell anemia- malaria protection
- retinoblastoma- enhanced neural growth/neural plasticity in early life
Explains the continued presence of recessive alleles that lead to disease
Genetic drift
- small populations
- eliminates minor variants
Prenatal Karyotyping
will NOT tell you what allele is present on the chromosome
Hybrid vigor
- does NOT apply to humans
- it’s from breeding 2 different species and having viable offspring (although they are generally infertile)
Know the structure of ceramide and phosphocholine, a sphingomyelin (or PE)
https://en.wikipedia.org/wiki/Sphingomyelin
ATP Synthesis
- constant H+ gradient = Cellular respiration
- dissipate gradient = glycolysis, fermentation make ATP
Aspartate transaminase catalyzes what rxn?
Asp + a-ketoglutarate -> glu + oxaloacetate
(Asp -> oxalo, a-keto -> glu)
https://aaltoscientific.com/wp-content/uploads/2015/06/aspartate-transaminase1.jpg
Red hair or Green eyes
polygenic inheritance
-unmasking at blond hair
Cardiac output
amount of blood pumped out of heart per unit time
AaBbCc x AaBbCc = AABBCC probability?
Law of independent assortment
1/41/41/4 = 1/64
Muscles involved in walking
slow-oxidative
aerobic, resistant to fatigue
*see mamm phys muscle notes
Protein misfolding
- likely tertiary structure
- only quaternary if they specify there’s more than 1 subunit
-primary and secondary protein structure issues tend to come from gene mutations or translational errors
AchR
nAChR at neuromuscular junctions
mAChR at CNS and post-synaptic PNS
AChE receptors in all places
Bacteria…
do not do meiosis or mitosis
they do binary fission
they do not transfer whole genomes through conjugation; only plasmids or transposons
bacteria attach new DNA to` part of cell membrane during binary fission
Meselson-Stahl Expt
heavy nitrogen
semiconservative
gel electrophoresis
separates molecules by charge or size, not density
=won’t work w/ Meselson Stahl (mass, Density)
Lack of oxygen
cells release protons to make Hb release more oxygen
Connexin
gap junctions
Tight junctions
decrease ECF
What excretes water?
aquaporins
Hemidesmosomes
skin
attach epithelial cells to basement membrane
