AP Bio-Exam 2 Questions and
Answers|Latest Update
What acts as a scaffold for various cell-surface markers The phospholipid bilayer
What do membrane proteins do? Membrane proteins serve as channels for ions to cross
the membrane, are free to migrate laterally within the membrane and some play roles in cell
identification. Also, their position in the membrane is determined by their tertiary structure
What will happen if a plant cell is put in an environment which is hypertonic to the cytoplasm?
Water will diffuse out of the cell less than into the cell
What does endocytosis involve? Endocytosis involves the discharge of material from
vesicles at the cell surface
What's the difference between passive transport and active transport? They have different
energy requirements
, Describe the singer and Nicholson membrane model Singer and Nicholson membrane
model, aka "fluid mosaic model" because the phospholipids can move laterally within plane of
the membrane, and proteuns are embedded to give it special functions
What is protein kinase? A protein kinase is an enzyme that adds phosphate groups to
certain proteins
Examples of secondary messengers? DAG, cAMP, Ca++ & Nitric Oxide
Receptor proteins and well being? Receptor proteins are important to a cells well being
because some messengers cannot cross the plasma membrane and therefore need a mechanism to
activate a response
Which cell junction would keep cardiac cells from separating? The cell junction that
would best prevent cardiac (heart muscle) cells from separating are desmosomes, aka "anchoring
junctions"
Where is snaptic communication mostly observed? Snaptic communication is most often
observed between nerve cells
Answers|Latest Update
What acts as a scaffold for various cell-surface markers The phospholipid bilayer
What do membrane proteins do? Membrane proteins serve as channels for ions to cross
the membrane, are free to migrate laterally within the membrane and some play roles in cell
identification. Also, their position in the membrane is determined by their tertiary structure
What will happen if a plant cell is put in an environment which is hypertonic to the cytoplasm?
Water will diffuse out of the cell less than into the cell
What does endocytosis involve? Endocytosis involves the discharge of material from
vesicles at the cell surface
What's the difference between passive transport and active transport? They have different
energy requirements
, Describe the singer and Nicholson membrane model Singer and Nicholson membrane
model, aka "fluid mosaic model" because the phospholipids can move laterally within plane of
the membrane, and proteuns are embedded to give it special functions
What is protein kinase? A protein kinase is an enzyme that adds phosphate groups to
certain proteins
Examples of secondary messengers? DAG, cAMP, Ca++ & Nitric Oxide
Receptor proteins and well being? Receptor proteins are important to a cells well being
because some messengers cannot cross the plasma membrane and therefore need a mechanism to
activate a response
Which cell junction would keep cardiac cells from separating? The cell junction that
would best prevent cardiac (heart muscle) cells from separating are desmosomes, aka "anchoring
junctions"
Where is snaptic communication mostly observed? Snaptic communication is most often
observed between nerve cells
