Sunday, 24 June 2012
Biology stuff from the week 18-24/6/12
'Key part of plants' rapid response system revealed'
Plants can't run from predators or move into the shade at noon, they don't have teeth or claws or nervous systems, and they don't enjoy most of the other safety procedures that animals can do...
But they do have hormones. Auxin makes them grow at the right rate, and in the right direction; salicylic acid is used to self-sterilize against infections; and tannins are used to poison their insect predators.
They might be static and simplistic, but they're certainly not defenceless!
'I want to know where love is: Research develops first brain map of love and desire'
Even though the targets of l'amour are 'chosen' subjectively, the process of 'loving' is definitely an objective one - how many of us haven't felt those same, primeval urges?
The striatum is located inside the forebrain, and is the region that processes love (affectinoate desire) and lust (sexual desire)
- The sub-region that processes sexual desire is usually activated during all inately pleasurable experiences - sex, food...
- The sub-region that processes affectionate desire (the awful yearning) is involved in 'conditioning' - it determines whether we associate something with pleasureableness, and is therefore also involved in addiction to external drugs, fetishes, familiar places/programs/songs, etc.
This latter process is crucial to the role of pair-bonding - it gives each partner will to stick around, with the other, hence the "i never want to leave your side" drivel.
"While sexual desire has a very specific goal, love is more abstract and complex, so it's less dependent on the physical presence someone else"
'In-vivo imaging of the common house fly feeding'
It might only be a fly drinking, but this is pretty cool - you can see the fluid flowing through the animal, into its abdomen!
'Pesticides hit bumblebee reproduction'
Pesticides are damaging the reproductive behaviours of bees
'Anchoring points determine fate of stem cells'
The type of cell that a stem cell is going to grow into, is determined by the mechanical restrictions that it experiences, as it develops.
It was previously discovered that cells on soft substrates would grow into different cells than cells on hard substrates.
This research has shown that the anchoring points between the chemical structures of the cells and the substrate surface are what determine the end-product of that cell's growth.
Formly-anchored cells grew into bone cells, and softly-anchored cells grew into fat cells.
'Researchers solve mystery of long elephant pregnancy'
How do elephants maintain their pregnancies for two years? It turns out they use multiples of a structure known as the 'corpus luteum':
'Cigarette smoke damages DNA in reproductive cells of fathers, these changes inherited by offspring'
The DNA damage experienced by fathers who smoke (as well as mothers, of course) is also passed on to their offspring, leaving them with inherited health deficits.
"This provides evidence showing why men should be urged to stop smoking before trying to conceive in the same way women have been urged to quit. Interestingly, a fertile sperm cell takes about three months to fully develop; therefore men would ultimately need to quit smoking long before conception to avoid causing genetic problems."
Special goggles have revealed that babies resolve their abilities to see in 3D at 4 months old, whether they're born prematurely or not.
This demonstrates that it is the light stimulus that determines neuron-sight development - it is not an innate process, working in isolation from environment.