nim_opet

nim_opet t1_iyctp4f wrote

Reply to comment by KypDurron in TIL: Dogs don't have digestive enzymes in their saliva, nor can they chew side to side. Their jaws only allow for up-and-down movement because their diet doesn’t need as much chewing as ours does. by theotherbogart

Your jaw can move up/down and side to side; like when you chew gum; that’s how grinding works. You don’t need majorly exaggerated left-right movement; simple up-down will also move it sideways across the molar surfaces

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nim_opet t1_iycsiyu wrote

Reply to comment by vanriggs in TIL: Dogs don't have digestive enzymes in their saliva, nor can they chew side to side. Their jaws only allow for up-and-down movement because their diet doesn’t need as much chewing as ours does. by theotherbogart

Basically humans (and other omnivores like pigs, chimps etc, not to mention the herbivores) grind their food with their molars (that’s why they have wide grinding surfaces). Dogs, canines in general and cats especially have teeth specialized to hold onto meat and shred strips before swallowing since there’s no need to grind cell walls (animal cells don’t have cell walls like plant ones).

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nim_opet t1_iuix9j0 wrote

Reply to ELI5 Why can’t plants absorb nitrogen from the air? by Cool-Boy57

Atmospheric nitrogen is more or less inert; two atoms form a N2 molecule that is very stable; the bond between them is well balanced. Nitrogen in the form of nitrates in soil will easily break free in water solutions and form N^2- ions; plants can incorporate those easily into more complex molecules since it is unstable and needs to form compounds with something.

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nim_opet t1_iueogfp wrote

Reply to ELI5 Why are airport ceiling so high? by TrShry

You clearly have not been to LGA before it was deconstructed. It felt like a 3rd world bus terminal; dark and oppressive. Thousands of people queuing up even in 12’ ceilings very quickly turns unbearable

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