UKY BIO 152 Exam 2 UPDATED ACTUAL
Exam Questions and CORRECT Answers
describe the process of excitation-contraction coupling in skeletal muscles. - CORRECT
ANSWER - Secondary messages travel from the extra-cellular space to the intra-cellular
space
describe the process of excitation-contraction coupling in smooth muscles. - CORRECT
ANSWER - (cannot contract without Calcium) Excitation: involuntary; some groups
respond to neurotransmitters.. Contraction: Calcium is released by SR and enters from the
extracellular space.. then binds to calmodulin inside the cell, which can then lead to actin and
myosin contractions.
Describe how a signal transfers a message to its receptor. - CORRECT ANSWER - Signal
transduction via secondary messages.. Cell responds by opening ion channels and enzymes are
activated
Explain why hydrophobic signal receptors are in different locations of a target cell than
hydrophilic signal receptors.. - CORRECT ANSWER - Hydrophilic receptors are in the
outside(extra) while hydrophobic receptors are in the plasma membrane (intra).
2 major classes of cell surface receptors - CORRECT ANSWER - 1) G-protein coupled
receptors
2) Receptor Kinase
Describe G protein coupled receptors - CORRECT ANSWER - Most amplify signals as
they transfer it to the interior of the cell.. fast but short lived.
Describe Receptor Kinase - CORRECT ANSWER - Kinases are ezymes that transfer
phosphate groups, slow but longer lasting response
Unicellular - CORRECT ANSWER - having or consisting of a single cell
, simple multicellular organism - CORRECT ANSWER - an organism composed of one or
more cells that show little differentiation and remain in close contact with the external
environment.
Complex multicellular organism - CORRECT ANSWER - an organisms composed of one
or more cells that have cellular adhesion, cellular communication, and cellular differentiation.
Cellular adhesion molecules: - CORRECT ANSWER - proteins located on the cell surface
involved in binding with other cells or with the extracellular matrix in the cellular adhesion
process.
Cadherin: - CORRECT ANSWER - any of a class of cell-surface proteins involved in
selective cell-cell adhesion.
Integrin: - CORRECT ANSWER - any of a class of cell-surface proteins that bind to
laminins and other proteins in the extracellular matrix, thus holding cells in place.
Gap junction - CORRECT ANSWER - a type of cell-cell attachment structure that directly
connects the cytosolic components of adjacent animal cells, allowing the pages of water, ions,
and small molecules between the cells.
Plasmodesmata - CORRECT ANSWER - physical connections between two plant cells,
consisting of membrane-lined gaps in the cell walls through which the two cells' plasma
membranes, cytoplasm, and smooth ER can connect directly.
Differentiation - CORRECT ANSWER - the process by which any unspecialized cell
becomes a distinct cell type, usually by changes in gene expression.
Gene expression - CORRECT ANSWER - the set of processes, including transcription and
translation, that convert information in DNA into a product of a gene, most commonly a protein.
Exam Questions and CORRECT Answers
describe the process of excitation-contraction coupling in skeletal muscles. - CORRECT
ANSWER - Secondary messages travel from the extra-cellular space to the intra-cellular
space
describe the process of excitation-contraction coupling in smooth muscles. - CORRECT
ANSWER - (cannot contract without Calcium) Excitation: involuntary; some groups
respond to neurotransmitters.. Contraction: Calcium is released by SR and enters from the
extracellular space.. then binds to calmodulin inside the cell, which can then lead to actin and
myosin contractions.
Describe how a signal transfers a message to its receptor. - CORRECT ANSWER - Signal
transduction via secondary messages.. Cell responds by opening ion channels and enzymes are
activated
Explain why hydrophobic signal receptors are in different locations of a target cell than
hydrophilic signal receptors.. - CORRECT ANSWER - Hydrophilic receptors are in the
outside(extra) while hydrophobic receptors are in the plasma membrane (intra).
2 major classes of cell surface receptors - CORRECT ANSWER - 1) G-protein coupled
receptors
2) Receptor Kinase
Describe G protein coupled receptors - CORRECT ANSWER - Most amplify signals as
they transfer it to the interior of the cell.. fast but short lived.
Describe Receptor Kinase - CORRECT ANSWER - Kinases are ezymes that transfer
phosphate groups, slow but longer lasting response
Unicellular - CORRECT ANSWER - having or consisting of a single cell
, simple multicellular organism - CORRECT ANSWER - an organism composed of one or
more cells that show little differentiation and remain in close contact with the external
environment.
Complex multicellular organism - CORRECT ANSWER - an organisms composed of one
or more cells that have cellular adhesion, cellular communication, and cellular differentiation.
Cellular adhesion molecules: - CORRECT ANSWER - proteins located on the cell surface
involved in binding with other cells or with the extracellular matrix in the cellular adhesion
process.
Cadherin: - CORRECT ANSWER - any of a class of cell-surface proteins involved in
selective cell-cell adhesion.
Integrin: - CORRECT ANSWER - any of a class of cell-surface proteins that bind to
laminins and other proteins in the extracellular matrix, thus holding cells in place.
Gap junction - CORRECT ANSWER - a type of cell-cell attachment structure that directly
connects the cytosolic components of adjacent animal cells, allowing the pages of water, ions,
and small molecules between the cells.
Plasmodesmata - CORRECT ANSWER - physical connections between two plant cells,
consisting of membrane-lined gaps in the cell walls through which the two cells' plasma
membranes, cytoplasm, and smooth ER can connect directly.
Differentiation - CORRECT ANSWER - the process by which any unspecialized cell
becomes a distinct cell type, usually by changes in gene expression.
Gene expression - CORRECT ANSWER - the set of processes, including transcription and
translation, that convert information in DNA into a product of a gene, most commonly a protein.
