WorksheetsConstruction of the Cell Membrane and Passive Transport
Total questions: 10
Worksheet time: 10mins
Diffusion is defined as:
molecules from areas of higher concentration to areas of lower concentration.
specifically water from a high to low concentration
gas molecules across a membrane
molecules from an area of low to a higher concentration area
Which would NOT be a typical factor to impact the rate of diffusion across a cell membrane?
temperature
size of molecules
steepness of the concentration gradient
cholesterol embedded in the membrane
Facilitated diffusion requires
carrier proteins
enzymes
energy to move from low to high concentration
glycoproteins - with sugars attached
Facilitated diffusion is there to "help" things to cross the cell membrane but it's still diffusion. It's facilitated. What would be correct for needing a bit of help to cross the PLB?
sugars and amino acids since they are water-soluble
water and oxygen gas
carbon dioxide and oxygen
water and carbon dioxide
Which items will MOST EASILY just slip right through a cell membrane?
small, nonpolar molecules
small polar molecules, including water
large neutral particles
ions and macromolecules
Osmosis is each of the following EXCEPT... Which is FALSE about osmosis?
Requires ATP to force the water through aquaporins
Water specific movement DOWN the concentration gradient
Uses globular-shaped, pore proteins to diffuse past polar heads on the phospholipid bilayer since it may get stuck
Would not occur in a cell with 5% sugar dissolved in it if it is placed in an isotonic solution with 95% water and 5% solute.
Which of the following is untrue? Which is FALSE?
Aquaporins = allow diffusion of water, specifically called osmosis
Fibrous proteins, spanning the entire length of an animal cell, would only be used to stabilize that animal cell.
Globular proteins could be pores, channels, or glycoproteins
Glycoproteins are for cell recognition and may extend into the extracellular space
Which is FALSE? One of these is NOT true! Which is wrong?
Animal cell membranes have cholesterol in them for stability, to prevent melting or freezing.
The framework of any cell membrane is made up of phospholipids in a double layer.
Ions are necessary in your body for various functions, like making your muscles contract, so you need some sodium to live.
Protein pumps are only used during diffusion and are considered peripheral proteins.
Which is false? The incorrect statement is:
2 main types of proteins associated with the cell membrane are fibrous and globular proteins.
Globular proteins are made of many microfilaments and microtubules or microfibers and are tightly coiled.
Globular proteins include pores and channels which are specific for specific molecules to move through them.
Glycoproteins can be peripheral proteins with enzymes or sugars attached for cell recognition, almost like an antenna sticking out.
Which is FALSE?
Individual sugar molecules are never moving within a sugar cube since that cube of sugar is a solid lump.
Solid sugar will dissolve into liquid water. The two will mix until the sugar molecules are evenly spaced with the water and equilibrium is reached.
Sugar is a solute and water, since it is polar, is a solvent, when you create a syrup solution to feed hummingbirds.
Passive transport includes simple diffusion, facilitated diffusion, and osmosis.
