BIO202H5 Lecture Notes - Lecture 10: Photoreceptor Cell, Insulin-Like Growth Factor 1, Sodium-Potassium Alloy
Document Summary
Smoltification is transformation from parr to smolt . Changes in salinity tolerance, na-k pump and plasma membrane levels during smelt development. Hormone release can be affected by environment. As photoreception due to sunlight can affect the release of hormones. Such as growth hormone release is increased. Components of na-k pump increase in size, while others disappear. This occurs as salmon in freshwater are at risk of losing salt and so need components to retain salts. When smolt moves to salty water, they want to excrete excess salt and so the components change to accomodate for this. This changes the direction of na-cl transport in the gills. Development and size increase response of growth hormones (gh, Igf), cortisol, thyroid hormones (th, t4) as well as prolactin to photoperiod. The osmolarity has to increase in order to increase the amount of salts leaving the body. Increase in chloride trends in majority of freshwater lakes in north american lakes.
