The joint found in the skull would be Immovable joints
Same way glucose does. Lipids enter cells through channels similar to glucose ones, but designated for lipids instead of carbohydrates. Then lipase splits them into separate parts (fatty acids & glycerol I think). The glycerol can either be used to make pyruvic acid and the energy of breaking its bonds can be used to make ATP, or it can go to making glucose, which is stored for later use.
The last one because plants move oxygen out to the atmosphere while taking in C02
A nervous system because worms don't have nerves
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