Can oxygen and Carbon dioxide molecules move across the cell membrane without help?
Carbon dioxide can because it is non-polar, oxygen cannot because it is polar.
Oxygen can because it is non-polar, but Carbon dioxide can't because it is too
big
Yes, because they are both non-polar molecules and they are both very small.
Neither can because the phospholipids are tightly held together and nothing
passes through them.

there’s no image attached but i can if you want: )

lipid

explanation:

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.