PER 510 HUMAN PHYSIOLOGY
GUYTON & HALL TEXTBOOK OF
MEDICAL PHYSIOLOGY 14TH EDITION
BY JOHN E. HALL and MICHAEL E. HALL
Special Thank You to George E. Haynes
for Preparation of Power Point Slides
Instructor: Michael Campisi CCP
Unit One: Introduction to Physiology: The Cell and General Physiology
Chapter 2: The Cell and Its Functions
LEARNING OBJECTIVES
BY THE END OF THIS PRESENTATION, THE STUDENT SHOULD BE ABLE TO:
List the organizational components of cells
Explain the importance of the cytoskeleton and its involvement with cell junction types
List and explain the 14 important organelles found within eukaryotic cells
Understand the relationship with the nuclear material and the importance of chromosome telomeres
Understand how the science of epigenetics plays into a study of genetic control
THE CELLULAR BASIS OF ALL LIFE ON EARTH
The English scientist Robert Hooke first observed plant cells with a crude microscope in the late 1600s.
Then, in the 1830s two German scientists, Matthias Schleiden and Theodor Schwann, proposed that all
living things are composed of cells.
German pathologist Rudolf Virchow extended this idea by contending that cells arise only from other
cells.
1
, Since the late 1800s, cell research has been exceptionally fruitful and provided us with four concepts collectively known as the
CELL THEORY: all
things are made of cells
-
1) A cell is the basic structural and functional unit of living organisms. When you define cell properties, you define the
properties of life.
2) The activity of an organism depends on both the individual and the collective activities of its cells.
-
cells come from other cells
3) According to the principle of complementarity of structure and function, the biochemical activities of cells are
dictated by their shapes or forms, and by the relative number of their specific subcellular structures.
4) Continuity of life from one generation to another has a cellular basis.
Each of the 100 trillion cells in a human being is a living structure that can survive for months or many years, provided its
surrounding fluids contain appropriate nutrients.
To understand the function of organs and other structures of the body, it is essential that we first understand the basic
organization of the cell and the functions of its component parts.
► Organization of the Cell
Plasma Membrane: forms a selectively permeable boundary isolating the internal cellular environment
Protoplasm (Cytoplasm): this is a general term that refers to the five basic substances that make up the bulk of a cell:
1) Water -> Mostly
2) Electrolytes & ions-Na
I t ca. ,
3) Proteins
4) Lipids
5) Carbohydrates 3
Macro Molecules
1) Water
The principal fluid medium of a cell; in a concentration of 70 to 85 percent.
It has three basic states: solid, liquid, gas. (Under very rare circumstances, a plasma-like state can also form.)
Water is unlike any other substance on the planet.
Recently, researchers investigating the properties of water have found that when it’s heated to between 40 and 60 degrees Celsius
(104- and 140-degrees Fahrenheit), it hits a 'crossover temperature', and appears to start switching between two different states of
liquid. This “switching” phenomena causes water to exhibit a whole new set of physical and chemical properties depending on the state
it flips into.
Other properties of water include:
High cohesive and adhesive molecular forces
High Molecular surface Tension (Mercury is the highest)
High Specific Heat and Heat of Vaporization
High Boiling Point for its molecular weight and High Thermal Conductivity
High Heat of Fusion
Low density on Freezing
High Dielectric constant
Relatively, transparent
Incompressible under many conditions
Ionizes well and is a good solvent
2) Electrolytes
Important ions in the cell include potassium, magnesium, phosphate, sulfate, bicarbonate, sodium, chloride, and
calcium.
-
Play a role in Metabolism Proteins : structural = share and form -
> Cytoskeleton
3) Proteins
After water, the most abundant substances in most cells are proteins, which normally constitute 10 to 20 percent of
the cell mass. They are divided into two types: structural proteins and functional proteins. MetabolicProcesses
enzymes >
- Control
Structural proteins
are present in the cell mainly in the form of long filaments that are polymers of many individual protein
molecules.
A prominent use of such intracellular filaments is to form microtubules that provide the basis for the
cell’s “cytoskeleton”, or the mass of protein filaments that hold the parts of the cytoplasm and
nucleoplasm together in their respective compartments, plus such cellular organelles as cilia,
flagella, and the mitotic spindles of dividing cells.
In the Extracellular matrix (ECM), fibrillar structural proteins are found especially in the
collagen and elastin fibers of connective tissue and in blood vessel walls, tendons, ligaments, and
many other structures.
Functional proteins
These proteins are mainly the enzymes of the cell and, in contrast to the fibrillar proteins, are often mobile
in the cell fluid. Also, many of them are adherent to or housed within membranous structures inside the cell.
-
tell genes to turn on and Produce Stuff
2
, 4) Lipids
Lipids are several types of substances that are grouped together because of their common property of being soluble in fat solvents.
Especially important lipids are phospholipids and cholesterol, which together constitute only about 2 percent of the total cell mass.
The significance of phospholipids and cholesterol is that they are mainly insoluble in water and, therefore, are used to form the cell
membrane and intracellular membrane barriers that separate the different cell compartments.
In addition to phospholipids and cholesterol, some cells contain large quantities of triglycerides, also called neutral fat.
In the fat cells, triglycerides often account for as much as 95 percent of the cell mass.
The fat stored in these cells represents the body's main storehouse of energy-giving nutrients that can later be used to provide energy
wherever in the body it is needed.
5) Carbohydrates
main function = energy synthesis
Carbohydrates have little structural function in the cell except as parts of glycoprotein (proteoglycan) molecules, but they play a
major role in nutrition of the cell.
Most human cells do not maintain large stores of carbohydrates; the amount usually averages about 1 percent of their total mass but
increases to as much as 3 percent in muscle cells and, occasionally, 6 percent in liver cells.
However, carbohydrate in the form of dissolved glucose is always present in the surrounding extracellular fluid so that it is readily
available to the cell.
Also, a small amount of carbohydrate is stored in the cells in the form of glycogen, which is an insoluble polymer of glucose that can be
depolymerized and used rapidly to supply the cells’ energy needs.
LINES OF EVOLUTION:
It all started about 3.5 to 3.8 billion years ago during the Precambrian Period with the appearance of
heterotrophic prokaryotic cells. This line of prokaryotic cells eventually evolved into an additional
line the autotrophic prokaryotic cells. These two lines of prokaryotic cells around a billion years
later became more complex and evolved into the cells of higher organisms called eukaryotic cells
(about 2.7 billion years ago). The eukaryotic cells like the prokaryotic split into two lines the
Autotroph and the Heterotroph.
The two lines of prokaryotic and the two lines of the eukaryotic cells still exist today. The scope of our
discussion, however, will be limited to the Heterotrophic Eukaryotic cells.
AUTOTROPH EUKARYOTIC HETEROTROPH EUKARYOTIC
The approximately 100 trillion
cells that make up the adult
human body include over 200 Nucleic acids = DNA and RNA
different cell types that vary
greatly in shape, size, and
function.
The cell is not merely a bag of
fluid, enzymes, and chemicals; it
also contains highly organized
physical structures, called
intracellular organelles.
The physical nature of each
organelle is as important as the
cell's chemical constituents for cell
function.
Many of these organelles are
essential to the life of the cell.
We will now begin to look at the
most important organelles and
other structures of the
eukaryotic cell.
3
GUYTON & HALL TEXTBOOK OF
MEDICAL PHYSIOLOGY 14TH EDITION
BY JOHN E. HALL and MICHAEL E. HALL
Special Thank You to George E. Haynes
for Preparation of Power Point Slides
Instructor: Michael Campisi CCP
Unit One: Introduction to Physiology: The Cell and General Physiology
Chapter 2: The Cell and Its Functions
LEARNING OBJECTIVES
BY THE END OF THIS PRESENTATION, THE STUDENT SHOULD BE ABLE TO:
List the organizational components of cells
Explain the importance of the cytoskeleton and its involvement with cell junction types
List and explain the 14 important organelles found within eukaryotic cells
Understand the relationship with the nuclear material and the importance of chromosome telomeres
Understand how the science of epigenetics plays into a study of genetic control
THE CELLULAR BASIS OF ALL LIFE ON EARTH
The English scientist Robert Hooke first observed plant cells with a crude microscope in the late 1600s.
Then, in the 1830s two German scientists, Matthias Schleiden and Theodor Schwann, proposed that all
living things are composed of cells.
German pathologist Rudolf Virchow extended this idea by contending that cells arise only from other
cells.
1
, Since the late 1800s, cell research has been exceptionally fruitful and provided us with four concepts collectively known as the
CELL THEORY: all
things are made of cells
-
1) A cell is the basic structural and functional unit of living organisms. When you define cell properties, you define the
properties of life.
2) The activity of an organism depends on both the individual and the collective activities of its cells.
-
cells come from other cells
3) According to the principle of complementarity of structure and function, the biochemical activities of cells are
dictated by their shapes or forms, and by the relative number of their specific subcellular structures.
4) Continuity of life from one generation to another has a cellular basis.
Each of the 100 trillion cells in a human being is a living structure that can survive for months or many years, provided its
surrounding fluids contain appropriate nutrients.
To understand the function of organs and other structures of the body, it is essential that we first understand the basic
organization of the cell and the functions of its component parts.
► Organization of the Cell
Plasma Membrane: forms a selectively permeable boundary isolating the internal cellular environment
Protoplasm (Cytoplasm): this is a general term that refers to the five basic substances that make up the bulk of a cell:
1) Water -> Mostly
2) Electrolytes & ions-Na
I t ca. ,
3) Proteins
4) Lipids
5) Carbohydrates 3
Macro Molecules
1) Water
The principal fluid medium of a cell; in a concentration of 70 to 85 percent.
It has three basic states: solid, liquid, gas. (Under very rare circumstances, a plasma-like state can also form.)
Water is unlike any other substance on the planet.
Recently, researchers investigating the properties of water have found that when it’s heated to between 40 and 60 degrees Celsius
(104- and 140-degrees Fahrenheit), it hits a 'crossover temperature', and appears to start switching between two different states of
liquid. This “switching” phenomena causes water to exhibit a whole new set of physical and chemical properties depending on the state
it flips into.
Other properties of water include:
High cohesive and adhesive molecular forces
High Molecular surface Tension (Mercury is the highest)
High Specific Heat and Heat of Vaporization
High Boiling Point for its molecular weight and High Thermal Conductivity
High Heat of Fusion
Low density on Freezing
High Dielectric constant
Relatively, transparent
Incompressible under many conditions
Ionizes well and is a good solvent
2) Electrolytes
Important ions in the cell include potassium, magnesium, phosphate, sulfate, bicarbonate, sodium, chloride, and
calcium.
-
Play a role in Metabolism Proteins : structural = share and form -
> Cytoskeleton
3) Proteins
After water, the most abundant substances in most cells are proteins, which normally constitute 10 to 20 percent of
the cell mass. They are divided into two types: structural proteins and functional proteins. MetabolicProcesses
enzymes >
- Control
Structural proteins
are present in the cell mainly in the form of long filaments that are polymers of many individual protein
molecules.
A prominent use of such intracellular filaments is to form microtubules that provide the basis for the
cell’s “cytoskeleton”, or the mass of protein filaments that hold the parts of the cytoplasm and
nucleoplasm together in their respective compartments, plus such cellular organelles as cilia,
flagella, and the mitotic spindles of dividing cells.
In the Extracellular matrix (ECM), fibrillar structural proteins are found especially in the
collagen and elastin fibers of connective tissue and in blood vessel walls, tendons, ligaments, and
many other structures.
Functional proteins
These proteins are mainly the enzymes of the cell and, in contrast to the fibrillar proteins, are often mobile
in the cell fluid. Also, many of them are adherent to or housed within membranous structures inside the cell.
-
tell genes to turn on and Produce Stuff
2
, 4) Lipids
Lipids are several types of substances that are grouped together because of their common property of being soluble in fat solvents.
Especially important lipids are phospholipids and cholesterol, which together constitute only about 2 percent of the total cell mass.
The significance of phospholipids and cholesterol is that they are mainly insoluble in water and, therefore, are used to form the cell
membrane and intracellular membrane barriers that separate the different cell compartments.
In addition to phospholipids and cholesterol, some cells contain large quantities of triglycerides, also called neutral fat.
In the fat cells, triglycerides often account for as much as 95 percent of the cell mass.
The fat stored in these cells represents the body's main storehouse of energy-giving nutrients that can later be used to provide energy
wherever in the body it is needed.
5) Carbohydrates
main function = energy synthesis
Carbohydrates have little structural function in the cell except as parts of glycoprotein (proteoglycan) molecules, but they play a
major role in nutrition of the cell.
Most human cells do not maintain large stores of carbohydrates; the amount usually averages about 1 percent of their total mass but
increases to as much as 3 percent in muscle cells and, occasionally, 6 percent in liver cells.
However, carbohydrate in the form of dissolved glucose is always present in the surrounding extracellular fluid so that it is readily
available to the cell.
Also, a small amount of carbohydrate is stored in the cells in the form of glycogen, which is an insoluble polymer of glucose that can be
depolymerized and used rapidly to supply the cells’ energy needs.
LINES OF EVOLUTION:
It all started about 3.5 to 3.8 billion years ago during the Precambrian Period with the appearance of
heterotrophic prokaryotic cells. This line of prokaryotic cells eventually evolved into an additional
line the autotrophic prokaryotic cells. These two lines of prokaryotic cells around a billion years
later became more complex and evolved into the cells of higher organisms called eukaryotic cells
(about 2.7 billion years ago). The eukaryotic cells like the prokaryotic split into two lines the
Autotroph and the Heterotroph.
The two lines of prokaryotic and the two lines of the eukaryotic cells still exist today. The scope of our
discussion, however, will be limited to the Heterotrophic Eukaryotic cells.
AUTOTROPH EUKARYOTIC HETEROTROPH EUKARYOTIC
The approximately 100 trillion
cells that make up the adult
human body include over 200 Nucleic acids = DNA and RNA
different cell types that vary
greatly in shape, size, and
function.
The cell is not merely a bag of
fluid, enzymes, and chemicals; it
also contains highly organized
physical structures, called
intracellular organelles.
The physical nature of each
organelle is as important as the
cell's chemical constituents for cell
function.
Many of these organelles are
essential to the life of the cell.
We will now begin to look at the
most important organelles and
other structures of the
eukaryotic cell.
3
