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CELL BIOLOGY 112 EXAM 3 PCC EXAM NEWEST 2026 ACTUAL
EXAM WITH COMPLETE QUESTIONS AND CORRECT DETAILED
ANSWERS (100% VERIFIED ANSWERS) |ALREADY GRADED A+|
||PROFESSOR VERIFIED||
What are the 6 classes of intermediate filaments used for? -
ANSWER-for diagnostic medicine.
ALL receptors are ___ - ANSWER-Proteins
Type of signaling for "long distances"
-Like sending a letter - ANSWER-Endocrine
Type of signaling for "Localized" substances - ANSWER-
Paracrine
"Self signaling" - ANSWER-Autocrine
What are the 3 steps that describe Endocrine signaling? -
ANSWER-Hormone Secretion -> diffuse in blood -> targets cells
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excocytosis secretes signal and targets protein receptors on
another cell, what is this known as? - ANSWER-Localized
diffusion, or paracrine
release signal by exocytosis and then receive them at receptors,
what kind of signaling is this? - ANSWER-Autocrine, or self
signaling
A greater portion of cancer is caused by what type of signaling? -
ANSWER-Autocrine, or self signaling
Signaling by plasma membrane-attatched proteins involves how
many cells? - ANSWER-Involves 2 cells; like shaking hands
Ex: immune system -> T helper cells -> receive info on
virus/bacteria and inform B cell by this process
Signal transduction pathway involves what 2 things? - ANSWER--
Effector that produces a second messenger
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-cascade of proteins in the cytosol transfer signal to the activated
target protein
enzymes that adds phosphate to another protein (phosphatease
removes phosphate; reverse action) - ANSWER-Kinase
What happens when a protein is phosphoralized? - ANSWER-It is
activated:
inactive —> active (this is the cascade effect
One ligand is amplified into many _______ - ANSWER-
Intracellular molecules
What are the 3 things signals can do at the end of signal
amplification? - ANSWER-1. Signals can converge and intergrate
2. Signals can diverge as well and form cascade branches
3. Signals can be interconnected
Olfactory receptors are _____ - ANSWER-G-proteins
, 4|Page
**G-proteins are transmembrane protein receptors
-have extracellular loops —> messenger binding site (where
ligands bind to achieve conformational change) change of shape
will cause activation of G protein!! - ANSWER-
GDP-bound G protein is in _____ form at the beginning of signal
transduction - ANSWER-inactive form
**When a receptor is activated by ligand binding, the receptor-
ligand complex associates with the G protein, causing the
displacement of GDP by GTP, and the dissociation of the α-
subunit-GTP complex.
Beta and gamma always together. The alpha subunit determines
functionality
after: activate g-protein will have GTP attached to alpha subunit.
GTP=ACTIVATED
Inactive/Active is like a molecular switch
To switch back —>GTPase (hydrolyze GTP to GDP) - ANSWER-
CELL BIOLOGY 112 EXAM 3 PCC EXAM NEWEST 2026 ACTUAL
EXAM WITH COMPLETE QUESTIONS AND CORRECT DETAILED
ANSWERS (100% VERIFIED ANSWERS) |ALREADY GRADED A+|
||PROFESSOR VERIFIED||
What are the 6 classes of intermediate filaments used for? -
ANSWER-for diagnostic medicine.
ALL receptors are ___ - ANSWER-Proteins
Type of signaling for "long distances"
-Like sending a letter - ANSWER-Endocrine
Type of signaling for "Localized" substances - ANSWER-
Paracrine
"Self signaling" - ANSWER-Autocrine
What are the 3 steps that describe Endocrine signaling? -
ANSWER-Hormone Secretion -> diffuse in blood -> targets cells
,2|Page
excocytosis secretes signal and targets protein receptors on
another cell, what is this known as? - ANSWER-Localized
diffusion, or paracrine
release signal by exocytosis and then receive them at receptors,
what kind of signaling is this? - ANSWER-Autocrine, or self
signaling
A greater portion of cancer is caused by what type of signaling? -
ANSWER-Autocrine, or self signaling
Signaling by plasma membrane-attatched proteins involves how
many cells? - ANSWER-Involves 2 cells; like shaking hands
Ex: immune system -> T helper cells -> receive info on
virus/bacteria and inform B cell by this process
Signal transduction pathway involves what 2 things? - ANSWER--
Effector that produces a second messenger
,3|Page
-cascade of proteins in the cytosol transfer signal to the activated
target protein
enzymes that adds phosphate to another protein (phosphatease
removes phosphate; reverse action) - ANSWER-Kinase
What happens when a protein is phosphoralized? - ANSWER-It is
activated:
inactive —> active (this is the cascade effect
One ligand is amplified into many _______ - ANSWER-
Intracellular molecules
What are the 3 things signals can do at the end of signal
amplification? - ANSWER-1. Signals can converge and intergrate
2. Signals can diverge as well and form cascade branches
3. Signals can be interconnected
Olfactory receptors are _____ - ANSWER-G-proteins
, 4|Page
**G-proteins are transmembrane protein receptors
-have extracellular loops —> messenger binding site (where
ligands bind to achieve conformational change) change of shape
will cause activation of G protein!! - ANSWER-
GDP-bound G protein is in _____ form at the beginning of signal
transduction - ANSWER-inactive form
**When a receptor is activated by ligand binding, the receptor-
ligand complex associates with the G protein, causing the
displacement of GDP by GTP, and the dissociation of the α-
subunit-GTP complex.
Beta and gamma always together. The alpha subunit determines
functionality
after: activate g-protein will have GTP attached to alpha subunit.
GTP=ACTIVATED
Inactive/Active is like a molecular switch
To switch back —>GTPase (hydrolyze GTP to GDP) - ANSWER-
