Question

1. match the words to their meanings. make 3 pairs! a. diffusion b. facilitated diffusion c. active transport d. passive transport of particles through a channel protein e. transport of particles through a channel protein that requires energy f. transport of particles directly through the membrane from high to low 11. active transport requires ____ (energy) and particles move __ the gradient. note: when particles move from high concentration to low concentration this is with or along the gradient. when particles move from __ to __ concentration this is against the gradient. 12. do carbohydrate antennaes go on the outside or the inside of the cell membrane? 13. what did the carbohydrate say to the white blood cell? challenge 2: membrane structure challenge 1. draw a phospholipid. label the head and tails. 2. what type of particle is moving through proteins in this model? 3. is facilitated diffusion a passive or active process? 4. how do you know that the ion+ is moving through active transport? (2 reasons) a. __ to __ concentration b. requires ____ 5. what molecule stabilizes the membrane? 6. draw the molecule you listed for #5.

Explanation:

1. Diffusion is the transport of particles directly through the membrane from high to low gradient (a & f). Facilitated diffusion is the passive transport of particles through a channel protein (b & d). Active transport is the transport of particles through a channel protein that requires energy (c & e).
2. Active transport requires energy and particles move against the gradient. When particles move from low to high concentration, it is against the gradient.
3. Carbohydrate antennae go on the outside of the cell - membrane. They are involved in cell - cell recognition and signaling.
4. This is a non - scientific, likely a joke question. There is no real biological answer.

Challenge 2:

1. A phospholipid has a hydrophilic head (composed of a phosphate group) and two hydrophobic tails (fatty acid chains).
2. Ions or small polar molecules are typically the particles moving through proteins in a cell - membrane model.
3. Facilitated diffusion is a passive process as it does not require energy input and moves particles along their concentration gradient.
4. a. Ion+ is moving from low to high concentration. b. Requires energy.
5. Cholesterol stabilizes the membrane. It helps maintain fluidity at different temperatures.
6. Cholesterol has a steroid - like structure with a four - ring core and a hydrocarbon tail.

Answer:

1. a & f; b & d; c & e
2. energy; against; low; high
3. outside
4. N/A (joke question)

Challenge 2:

1. Draw a structure with a head (phosphate group) and two tails (fatty acid chains)
2. Ions or small polar molecules
3. passive
4. a. low; high b. energy
5. cholesterol
6. Draw a steroid - like structure with a four - ring core and a hydrocarbon tail