carriage of oxygen in the blood Flashcards
what are the roles of the cardiovascular system?
supply oxygen and metabolic fuel to tissues
remove metabolic waste from tissues
defence against pathogens
what is oxidation?
loss of electrons
what is an oxidising agent?
a substance that is reduced so that it can oxidise another molecule
give examples of oxidising agents in anaerobic bacteria
sulphate
nitrate
sulphur
what does oxidation do to a substrate?
simplifies the electronic structure
releases energy
what is reduction?
gain of electrons
what does reduction do to substrates?
allows complex molecules to be made from simple ones
requires energy
when are oxidation reactions irreversible?
when they release a large amount of energy
what does NAD stand for?
nicotinamide adenine dinucleotide
how is NAD used in the body?
NADH gives electrons
NAD can store electrons
give an equation for NAD to NADH
NAD+ + H+ + 2e- –> NADH
what is microcytic anaemia?
smaller than usual RBCs
what is microcytic anaemia?
larger than usual RBCs
what are reticulocytes?
immature RBCs that have just left the bone marrow
what % of RBCs are reticulocytes?
1-2%
how long does it take for reticulocytes to turn into mature RBCs?
1 day after being in circulation
how is the rRNA arranged in reticulocytes?
reticular, mesh-like structure
what does a blood smear with high levels of reticulocytes show?
lots of haemolysis
why can RBCs not repair themselves?
they don’t have a nucleus or organelles
how long do RBCs survive in the bloodstream?
120 days
why do RBCs require a small amount of ATP?
maintain the Na+ pumps in the cell membranes
actin filaments
how do RBCs make ATP?
glycolysis
what is the glucose uptake system in RBCs?
glut1 - works by facilitated diffusion
what is the pH of RBCs?
low - acidic