Membrane Transport

Channels and sodium-potassium ion pumps in the cell membrane that act like gates to help carry particles across the membrane are made up of ______________

• proteins
• carbohydrates
• nucleotides
• fatty acids

The cell membrane is important in cell functions in that 

• all cell functions occur in the cell membrane
• energy transfers across the cell membrane
• all materials for cell functions cross the cell membrane
• information for making proteins is contained in the cell membrane

Diffusion is the movement of molecules from an area of _____________ concentration.

• low to high
• high to low
• equal to high
• all of these

Tags

NGSS.MS-PS1-4

When the solutions on both sides of a membrane are isotonic or the same concentration, the molecules will

• not move at all
• move to the outside of cell
• move to the inside of cell
• move in both directions in and out at same rate

The diffusion of water is known as _________

• active transport
• facilitated diffusion
• osmosis
• pinocytosis

Iodine turns dark purple when in contact with starch. After an hour, the solution in the dialysis tubing turned dark purple. Why?

• The starch in the tubing diffused out.
• The iodine and water diffused in.
• The iodine changed into starch.
• The starch changed into iodine

Tags

NGSS.HS-LS2-3

Consider the virtual cell membrane lab from class.  Which will not move across the selectively permeable dialysis membrane?

• water
• iodine
• starch and glucose
• water and iodine

In this example, the iodine and water move into the hypertonic starch and glucose solution inside the bag by the process of ________.

• endocytosis
• facilitated diffusion
• osmosis
• exocytosis

Sailors cannot drink salt water because...

• it is poisonous to humans
• it is hypertonic to human tissue
• it is hypotonic to human tissue
• it is isotonic to human tissue.

This diagram is showing...

• endocytosis
• exocytosis
• osmosis
• diffusion

Tags

NGSS.MS-LS1-2