lOMoARcPSD|27929433
, lOMoARcPSD|27929433
McCance/Huether: Pathophysiology: The Biologic Basis of Disease in Adults
and Children, 8th Edition
Chapter 01: Cellular
Biology Chapter Summary
Review Cellular Functions
1. Cells become specialized through the process of differentiation, or maturation.
2. The eight specialized cellular functions are movement, conductivity,
metabolic absorption, secretion, excretion, respiration, reproduction, and
communication.
Structure and Function of Cellular Components
1. The eukaryotic cell consists of three general components: the plasma membrane,
the cytoplasm, and the intracellular organelles.
2. The nucleus is the largest membrane-bound organelle and is usually found in the cell’
s center. The chief functions of the nucleus are cell division and control of genetic
information.
3. Cytoplasm, or the cytoplasmic matrix, is an aqueous solution (cytosol) that fills the space
between the nucleus and the plasma membrane.
4. The organelles are suspended in the cytoplasm and are enclosed in biologic membranes.
5. The endoplasmic reticulum (ER) is a network of tubular channels (cisternae) that extends
throughout the outer nuclear membrane. It specializes in the synthesis and transport of
protein and lipid components of most of the organelles. Importantly, the ER is
responsible for protein folding and sensing cell stress.
6. The Golgi complex is a network of smooth membranes and vesicles located near the
nucleus. The Golgi complex is responsible for processing and packaging proteins into
secretory vesicles that break away from the Golgi complex and migrate to a variety
of intracellular and extracellular destinations, including the plasma membrane.
7. Lysosomes are saclike structures that originate from the Golgi complex and contain
digestive enzymes. These enzymes are responsible for digesting most cellular
substances completely to their basic components, such as amino acids, fatty acids, and
carbohydrates. A newly understood role of lysosomes is nutrient-dependent signal
transduction. The signaling function cooperates with the known degradative role to
mediate basic cell functions, such as nutrient sensing, metabolic adaptation, and quality
control of proteins and organelles.
8. Four pathways of degradation in lysosomes include endocytosis, phagocytosis
, macropinocytosis, and autophagy.
9. Peroxisomes are similar to lysosomes but contain several oxidative enzymes, such as
catalase and urate oxidase.
10. Mitochondria are found in great numbers in most cells and are responsible for cellular
respiration and energy production. The enzymes of the respiratory chain (electron-
transport chain), found in the inner membrane of the mitochondria, generate most of
the cell’s ATP.
..
.
, lOMoARcPSD|27929433
Chapter Summary Review 1-2
11. The cytosol or liquid portion of the cytoplasm has several functions including
intermediary metabolism involving enzymatic biochemical reactions; ribosomal
protein synthesis; and storage of carbohydrates, fat, and secretory vesicles.
12. The cytoskeleton is the “bone and muscle” of the cell. The internal skeleton is
composed of a network of protein filaments including microtubules and actin filaments (
microfilaments).
13. The plasma membrane encloses the cell and, by controlling the movement of
substances across it, exerts a powerful influence on metabolic pathways.
14. The plasma membrane is a bilayer of lipids and proteins. The basic structure of the
cell membrane is the lipid bilayer.
15. Membrane functions are determined largely by proteins. These functions include (a)
recognition and binding units (receptors) for substances moving in and out of the cell; (b)
pores or transport channels; (c) enzymes that drive active pumps; (d) cell surface
markers, such as glycoproteins; (e) cell adhesion molecules; and (f) catalysts of chemical
reactions.
16. The information regarding concepts of biologic membranes has changed markedly in
the last two decades.
17. A protein is made from a chain of amino acids known as polypeptides. Proteins are the
major workhorses of the cell . Proteins move from one compartment to another by
gated transport, protein translocation, or vesicular transport.
18. Proteostasis is a state of cell balance of the processes of protein synthesis, folding,
and degradation. Proteostasis is vital to cellular health.
19. Cellular receptors are protein molecules on the plasma membrane, in the cytoplasm, or in
the nucleus that are capable of recognizing and binding smaller molecules, called ligands
.
20. The ligand-receptor complex initiates a series of protein interactions, causing
adenylyl cyclase to catalyze the transformation of cellular ATP to messenger
molecules that stimulate specific responses within the cell.
21. The carbohydrate contained within the plasma membrane is generally bound
to membrane proteins.
Cell-to-Cell Adhesions
1. Cell-to-cell adhesions are formed on plasma membranes, thereby allowing the
formation of tissues and organs. Cells are held together by three different means: (a) the
extracellular membrane, (b) cell adhesion molecules in the cell’s plasma membrane, and
(c) specialized cell junctions.
2. The extracellular matrix includes three types of protein fibers: collagen, elastin, and
fibronectin. The matrix helps regulate cell growth and differentiation.
3. The basement membrane is a thin layer of connective tissue underlying the epithelium
of many organs. It is also called the basal lamina.
4. Cell adhesion molecules (CAMs) are cell surface proteins that bind to an adjacent cell
and to components of the extracellular matrix. CAMs include four main protein families:
the integrins, the cadherins, the selectins, and the immunoglobulin (Ig) superfamily.
5. The three main types of cell junctions are desmosomes, tight junctions, and gap junctions.
Cellular Communication and Signal Transduction
..
.
, lOMoARcPSD|27929433
Chapter Summary Review 1-3
1. Cells communicate in three main ways: (a) they display plasma membrane–bound
signaling molecules (receptors) that affect the cell itself and other cells in direct physical
contact; (b) they activate receptor proteins inside the target cell, and the signal molecule
has to enter the cell to bind to them; and (c) they form protein channels (gap junctions)
that directly coordinate the activities of adjacent cells.
2. Primary modes of intercellular signaling are contact-dependent, paracrine, hormonal
, neurohormonal, and neurotransmitter.
3. Signal transduction involves signals or instructions from extracellular chemical
messengers that are conveyed to the cell’s interior for execution.
4. Signal transduction pathways (signaling cascades, relay chains) have several
important functions, including physically transferring the signal around the cell,
amplifying the signal, distributing the signal, and modulating the signal.
5. Two important second-messenger pathways are cAMP and Ca++.
6. G protein is an intermediary between the receptor and adenylyl cyclase.
7. Phospholipase C, an enzyme protein effector, is bound to the inner side of the membrane.
Cellular Metabolism
1. The chemical tasks of maintaining essential cellular functions are referred to as cellular
metabolism. Anabolism is the energy-using process of metabolism, whereas catabolism
is the energy-releasing process.
2. ATP functions as an energy-transferring molecule. Energy is stored by molecules of
carbohydrate, lipid, and protein, which, when catabolized, transfer energy to ATP.
3. Oxidative phosphorylation occurs in the mitochondria and is the mechanism by which
the energy produced from carbohydrates, fats, and proteins is transferred to ATP.
Membrane Transport: Cellular Intake and Output
1. Cell survival and growth depend on the constant exchange of molecules with their
environment. Simple diffusion across the lipid bilayer of the plasma membrane occurs
for important moles, such as O2 and CO2.
2. The majority of molecule transfer depends on specialized membrane transport proteins that
span the lipid bilayer and provide private thoroughfares for select molecules.
3. The two main classes of membrane transport proteins are transporters and channels.
4. Water and small, electrically uncharged molecules move through pores in the
plasma membrane’s lipid bilayer in the process called passive transport.
5. Passive transport does not require the expenditure of energy; rather, it is driven by
the physical effects of osmosis, hydrostatic pressure, and diffusion.
6. Larger molecules and molecular complexes (e.g., ligand-receptor complexes ) are moved
into the cell by active transport, which requires expenditure of energy (by means of ATP
) by the cell.
7. Two types of solutes exist in body fluids: electrolytes and nonelectrolytes.
Electrolytes are electrically charged and dissociate into constituent ions when placed
in solution. Nonelectrolytes do not dissociate when placed in solution.
..
.
, lOMoARcPSD|27929433
McCance/Huether: Pathophysiology: The Biologic Basis of Disease in Adults
and Children, 8th Edition
Chapter 01: Cellular
Biology Chapter Summary
Review Cellular Functions
1. Cells become specialized through the process of differentiation, or maturation.
2. The eight specialized cellular functions are movement, conductivity,
metabolic absorption, secretion, excretion, respiration, reproduction, and
communication.
Structure and Function of Cellular Components
1. The eukaryotic cell consists of three general components: the plasma membrane,
the cytoplasm, and the intracellular organelles.
2. The nucleus is the largest membrane-bound organelle and is usually found in the cell’
s center. The chief functions of the nucleus are cell division and control of genetic
information.
3. Cytoplasm, or the cytoplasmic matrix, is an aqueous solution (cytosol) that fills the space
between the nucleus and the plasma membrane.
4. The organelles are suspended in the cytoplasm and are enclosed in biologic membranes.
5. The endoplasmic reticulum (ER) is a network of tubular channels (cisternae) that extends
throughout the outer nuclear membrane. It specializes in the synthesis and transport of
protein and lipid components of most of the organelles. Importantly, the ER is
responsible for protein folding and sensing cell stress.
6. The Golgi complex is a network of smooth membranes and vesicles located near the
nucleus. The Golgi complex is responsible for processing and packaging proteins into
secretory vesicles that break away from the Golgi complex and migrate to a variety
of intracellular and extracellular destinations, including the plasma membrane.
7. Lysosomes are saclike structures that originate from the Golgi complex and contain
digestive enzymes. These enzymes are responsible for digesting most cellular
substances completely to their basic components, such as amino acids, fatty acids, and
carbohydrates. A newly understood role of lysosomes is nutrient-dependent signal
transduction. The signaling function cooperates with the known degradative role to
mediate basic cell functions, such as nutrient sensing, metabolic adaptation, and quality
control of proteins and organelles.
8. Four pathways of degradation in lysosomes include endocytosis, phagocytosis
, macropinocytosis, and autophagy.
9. Peroxisomes are similar to lysosomes but contain several oxidative enzymes, such as
catalase and urate oxidase.
10. Mitochondria are found in great numbers in most cells and are responsible for cellular
respiration and energy production. The enzymes of the respiratory chain (electron-
transport chain), found in the inner membrane of the mitochondria, generate most of
the cell’s ATP.
..
.
, lOMoARcPSD|27929433
Chapter Summary Review 1-2
11. The cytosol or liquid portion of the cytoplasm has several functions including
intermediary metabolism involving enzymatic biochemical reactions; ribosomal
protein synthesis; and storage of carbohydrates, fat, and secretory vesicles.
12. The cytoskeleton is the “bone and muscle” of the cell. The internal skeleton is
composed of a network of protein filaments including microtubules and actin filaments (
microfilaments).
13. The plasma membrane encloses the cell and, by controlling the movement of
substances across it, exerts a powerful influence on metabolic pathways.
14. The plasma membrane is a bilayer of lipids and proteins. The basic structure of the
cell membrane is the lipid bilayer.
15. Membrane functions are determined largely by proteins. These functions include (a)
recognition and binding units (receptors) for substances moving in and out of the cell; (b)
pores or transport channels; (c) enzymes that drive active pumps; (d) cell surface
markers, such as glycoproteins; (e) cell adhesion molecules; and (f) catalysts of chemical
reactions.
16. The information regarding concepts of biologic membranes has changed markedly in
the last two decades.
17. A protein is made from a chain of amino acids known as polypeptides. Proteins are the
major workhorses of the cell . Proteins move from one compartment to another by
gated transport, protein translocation, or vesicular transport.
18. Proteostasis is a state of cell balance of the processes of protein synthesis, folding,
and degradation. Proteostasis is vital to cellular health.
19. Cellular receptors are protein molecules on the plasma membrane, in the cytoplasm, or in
the nucleus that are capable of recognizing and binding smaller molecules, called ligands
.
20. The ligand-receptor complex initiates a series of protein interactions, causing
adenylyl cyclase to catalyze the transformation of cellular ATP to messenger
molecules that stimulate specific responses within the cell.
21. The carbohydrate contained within the plasma membrane is generally bound
to membrane proteins.
Cell-to-Cell Adhesions
1. Cell-to-cell adhesions are formed on plasma membranes, thereby allowing the
formation of tissues and organs. Cells are held together by three different means: (a) the
extracellular membrane, (b) cell adhesion molecules in the cell’s plasma membrane, and
(c) specialized cell junctions.
2. The extracellular matrix includes three types of protein fibers: collagen, elastin, and
fibronectin. The matrix helps regulate cell growth and differentiation.
3. The basement membrane is a thin layer of connective tissue underlying the epithelium
of many organs. It is also called the basal lamina.
4. Cell adhesion molecules (CAMs) are cell surface proteins that bind to an adjacent cell
and to components of the extracellular matrix. CAMs include four main protein families:
the integrins, the cadherins, the selectins, and the immunoglobulin (Ig) superfamily.
5. The three main types of cell junctions are desmosomes, tight junctions, and gap junctions.
Cellular Communication and Signal Transduction
..
.
, lOMoARcPSD|27929433
Chapter Summary Review 1-3
1. Cells communicate in three main ways: (a) they display plasma membrane–bound
signaling molecules (receptors) that affect the cell itself and other cells in direct physical
contact; (b) they activate receptor proteins inside the target cell, and the signal molecule
has to enter the cell to bind to them; and (c) they form protein channels (gap junctions)
that directly coordinate the activities of adjacent cells.
2. Primary modes of intercellular signaling are contact-dependent, paracrine, hormonal
, neurohormonal, and neurotransmitter.
3. Signal transduction involves signals or instructions from extracellular chemical
messengers that are conveyed to the cell’s interior for execution.
4. Signal transduction pathways (signaling cascades, relay chains) have several
important functions, including physically transferring the signal around the cell,
amplifying the signal, distributing the signal, and modulating the signal.
5. Two important second-messenger pathways are cAMP and Ca++.
6. G protein is an intermediary between the receptor and adenylyl cyclase.
7. Phospholipase C, an enzyme protein effector, is bound to the inner side of the membrane.
Cellular Metabolism
1. The chemical tasks of maintaining essential cellular functions are referred to as cellular
metabolism. Anabolism is the energy-using process of metabolism, whereas catabolism
is the energy-releasing process.
2. ATP functions as an energy-transferring molecule. Energy is stored by molecules of
carbohydrate, lipid, and protein, which, when catabolized, transfer energy to ATP.
3. Oxidative phosphorylation occurs in the mitochondria and is the mechanism by which
the energy produced from carbohydrates, fats, and proteins is transferred to ATP.
Membrane Transport: Cellular Intake and Output
1. Cell survival and growth depend on the constant exchange of molecules with their
environment. Simple diffusion across the lipid bilayer of the plasma membrane occurs
for important moles, such as O2 and CO2.
2. The majority of molecule transfer depends on specialized membrane transport proteins that
span the lipid bilayer and provide private thoroughfares for select molecules.
3. The two main classes of membrane transport proteins are transporters and channels.
4. Water and small, electrically uncharged molecules move through pores in the
plasma membrane’s lipid bilayer in the process called passive transport.
5. Passive transport does not require the expenditure of energy; rather, it is driven by
the physical effects of osmosis, hydrostatic pressure, and diffusion.
6. Larger molecules and molecular complexes (e.g., ligand-receptor complexes ) are moved
into the cell by active transport, which requires expenditure of energy (by means of ATP
) by the cell.
7. Two types of solutes exist in body fluids: electrolytes and nonelectrolytes.
Electrolytes are electrically charged and dissociate into constituent ions when placed
in solution. Nonelectrolytes do not dissociate when placed in solution.
..
.
