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1. What are the 4 components that make up the plasma membrane?
Describe the structure of a phospholipid.
two layers of phospholipids: the fatty acid chains point towards each other
1. Differentiate between an integral protein and a peripheral protein.
Integral proteins are bound to the hydrophobic layer and peripheral proteins aren't.
Know the functions of the proteins associated with the plasma membrane.
What’s the glycocalyx? What is its function?
Carbohydrate chains are attached to membrane proteins or to phospholipid molecules. It's function is to serve as a binding site for other molecules.
Describe the function of cholesterol molecules in the plasma membrane.
Keeps some small molecules from enetering. Helps maintain the membrane's fluidity.
Explain what the fluid mosaic model states.
this molle comptualization views the membrane as a fliud phospholuipid bilayer that has within it a mosaic of stationary and mobile proteins
Differentiate between passive transport and active transport
passive transportation doesn't require energy to move substances across the cell membrane but active transport does.
Describe the process of diffusion. Use the term concentration gradient in your description.
mvement of molecvules or ions form a region of higher concentration to lower concentration. concentration gradient-a difference between solute concentrations.
How does facilitated diffusion differfrom simple diffusion?
facilitated diffusion is diffusion through cell membrane that utilizes a transport protein. simple diffusion is diffusion through cell membrane w/o a special protein.
What do we mean by semipermeable membrane?
water and lipids can move across but larger substances that carry -/+ cannot.
Explainhow osmosis works.
the net mnovement of water across a semipermeable membrane from an area of lower solute concentration to a higher solute concentration.
What will happen to a cell if it is placed in:
a. A hypertonic solution? Why?
b. A hypotonic solution? Why?
c. An isotonic solution? Why?
the cell water moves out
water moves in
water is balanced
What factors influence whether or not a molecule can diffuse across the plasma membrane?
the size and sign of the moleecule
1. Compare and contrast endocytosis and exocytosis.
endocytosis moving large substances INTO cell. Exocytosis moving large substance OUT of cell
1. How does pinocytosis differ from phagocytosis?
pinocytosis pinching off a vesicle to capture material
Explainhow ion pumps create an electrochemical gradient and why thisis necessary
one side of the plasma membrane is more -/+ than the other.
3 Na+ ions are pumped out of cell
2 K+ ions are pumped into cell
1. What are the three parts of the cell theory?
cells are beasic units of structure and function for ALL living things
All living things are composed of one or more cells
Cells come from pre-existing cells
1. Compare and contrast a prokaryotic cell to a eukaryotic cell.
eukaryotic cells have a nucleus and a membrane bound organlelles.
they both have kingdoms and are unicellular
1. List the 5 principal components of a eukaryotic cell.
cytosol- jellylike fliud inside of cell
houses our DNA
the site of DNA replication and transcription
where RNA is produced
the site of protein synthesis (translation) in the cell
transport of materials within the cell
processes and distributes proteins that come to it for RER
uses enzymes to digest worn-out organelles or foreign materials that enter a cell (animal cells)
the powerhouse of the cell- where ATP is produced (cell fuel)
rough endoplasmis reticulum
processes the proteins for export from the cell
smooth endoplasmic reticulum
detoxifies harmful substances
ex. detoxifies alcohol
stores H+ ions to allow plant cell to maintain
stores waste products only they can be degraded
stores waste which allows a plant cell to maintain a healthy internal pressure
the site of photosynthesis in plant and algae cells
provide structural strength rigidty
1. The cytoskeleton is made up of three different types of filaments. Name the three types and describe their function(s).
micrpfilaments-allows changes in cell shape
intermediate filaments-help cell to maintain its shape; stabilizes the position of the nucleus to there organelles
-determining the shape of cell
-movement of vesicles
-form the underlying structures needed for cililia and flagella which aid in cell mobility
1. Differentiate between cilia and flagella.
cilia- hairlike extensions that propel a cell or sweep material around the cell
flagella- a tail like extension that function in cell movement
1. What’s the difference between plasmodesmataand gap junctions?
plasmodesmata-tiny permanent channels in plant cell walls that link plamt cells topgether
gap junctions- integral plasma membrane proteins tha line up and form temporary channels for small molecular ions to pass through
Describethe path that a protein takes through the cell starting with DNA
1. What’s the difference between a polypeptide chain and a protein?
protein- ploymers made of amino acids
polypeptide chains- bond that link amino acids