What is a major difference between facilitated diffusion and active transport?
question 3 options:

active transport moves substances against the concentration gradient.

active transport uses proteins in the process.

facilitated diffusion moves molecules through the plasma membrane.

facilitated diffusion requires large amounts of energy.

Active transport moves substances against the concentration gradient

Explanation:

Facilitated diffusion moves their substances down their concentration gradient while  active transport moves substances against the concentration gradient. Facilitated diffusion is a passive process and does not require cellular energy. Active transport uses carrier proteins. Energy is used to change the shape of the carrier protein. Facilitated diffusion uses both gated channel proteins and carrier proteins in transport.

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.