Transcript Slide 1

How to use this PowerPoint presentation
• To watch the PowerPoint, click on the “Slide Show” menu and then
“View Show” or just hit “F5”.
• If you don’t want to hear the narration, mute or turn off your
computer speakers
• To skip ahead while watching the show, hit the space or arrow
button. You can also see all the slides and select the one you want
by clicking on the “View” menu and selecting “Slide Sorter.”
• To print out the presentation, click on the “File” menu, “Print.” Then
under “Print What”, select “Handouts” and Print 3, 4 or 6 slides per
page to save paper and printer ink. Otherwise each slide will print
on its own page
• Remember that this PowerPoint is an overview of the topic. Use
the book chapters and online web links from the course website to
fill in details. Some students like to follow along in the book, or
stop and view related websites.
• ENJOY!!! (E-mail me with any questions)
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Blood, Oxygen and Immunity
• Blood everywhere—
Circulation
• Oxygen for Cell
Respiration
• Immunity
• AIDS
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Blood, Oxygen and Immunity
• Blood
everywhere—
Circulation
• Oxygen for Cell Respiration
• Immunity
• AIDS
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Blood is everywhere…how?
• Circulatory system
– Big vessels leave from
pump—heart
– Divide and split to all
major parts of body:
•
•
•
•
•
•
Limbs
Head
Guts
Major organs
Body wall
Skeleton, muscles
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
“Stuff” moves in and
out of blood
• From/to outside world
– O2, CO2 in lungs
– Nutrients in guts/digestive
system
– metabolic wastes—
kidneys/urinary system
• From/To cells of body
– Every single tissue
– O2, CO2, nutrients, waste
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
“Stuff” moves in and out by diffusion
Inside organs, muscles, structures, bones, big vessels divide into smaller and
smaller vessels and then into network-like capillary beds. This is where
diffusion can happen rapidly, at the microscopic level. Then, to get blood back
to heart, capillaries feed into smaller veins into larger and larger veins into
major veins that return to heart
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Capillaries infiltrate every
tissue of the body (so
blood is everywhere!)
• Why? Because the cells
that make up every tissue
need
– Oxygen (for cellular
respiration)
– Nutrients (for cell
metabolism)
– Immune cells nearby (to
eliminate invading microbes)
– Removal of waste (from cell
metabolism)
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Capillaries—schematic view
•
•
•
•
Very schematic view of what happens in a capillary
Arteries bring blood from heart. Veins take blood to heart.
Network of capillaries really connects artery to vein
Diffusion of needed substances only happens in microscope, thin-walled
capillaries
• See next slide for more realistic view of capillary network or “capillary bed.”
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Capillaries—more realistic views
More realistic drawing
showing network of capillaries
connecting arteries to veins
and threading through tissue.
Open-ended lymph capillaries
pick up excess fluid from
tissue and also give immune
cells route back into blood
circulation
Photomicrograph of
stained blood vessels of
retina showing intricate
capillary network
Electron micrograph
showing arterioles,
tiniest of arteries,
splitting into virtual sheet
of capillary network that
brings blood into very
close proximity with
almost every cell in the
tissue.
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Heart pumps blood
•
•
•
•
If more oxygen is needed, heart pumps faster
Brain, guts are big users of oxygen
But muscles under physical activity are biggest user.
During exercise, more muscles are active, more oxygen is needed so heart
pumps faster
• Pulse is measure of how fast heart is pumping
• Learn to measure your own pulse—you’ll need to do this for the Lab Project
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Blood Pressure
• Blood pressure
measures force of
blood against wall of
vessels
• Systolic pressure is
highest point, as blood
is being forced out of
heart by contraction of
heart muscle
• Diastolic pressure is
lowest point, between
heart “beats,” when
heart is inactive
• Would you expect
these values to be
affected by physical
exercise—find out in
Lab Project for this unit!
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Blood, Oxygen and Immunity
• Blood everywhere—Circulation
• Oxygen for Cell
Respiration
• Immunity
• AIDS
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Why do cells need oxygen?
• Remember Cell Respiration (breaks down glucose to make
high-energy ATP bonds that can be used for cell metabolic
reactions)
– Glycolysis (can happen in absence of oxygen=fermentation)
– Citric acid cycle
– Electron transport chain
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
• Every step of
respiration
catalyzed by
proteins that are
coded for in the
DNA
• Can you find
cellular
respiration on the
E. coli metabolic
map?
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
How does oxygen get into blood?
• Oxygen diffuses into blood in lungs
• In lungs, bronchioles (air tubes) branch and branch, finally
ending in tiny sacs called alveoli.
• Each alveolus is surrounded by capillaries
• Oxygen diffuses across super-thin epithelial tissue of alveolus,
across super-thin epithelial tissue of capillary, across red blood
cell membrane and is held by Hemoglobin protein molecules in
Larry M. Frolich, Ph.D.
red blood cells
Biology Department, Yavapai College
Blood
Cells
• Red blood cells are one of several types of blood cells
• Each second, 3 million new red blood cells are formed by a special kind of
mitosis
• Red blood cells have no nucleus or organelles. They are just full of
Hemoglobin (Hb)
• Thus, Hb was one of the earliest proteins to be isolated and understood.
• It’s role in sickle cell anemia also helped to unlock the genetics and
molecular structure of Hemoglobin (see web links on the course website)
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Blood, Oxygen and Immunity
• Blood everywhere—Circulation
• Oxygen for Cell Respiration
• Immunity
• AIDS
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Blood
Cells
• White blood cells fight invading microbes as part of the immune
system
• Include
– Lymphocytes—recognize invaders
– Monocytes and neutrophils—actually consume or engulf microbes
– Basophils—release substances that trigger the other cells.
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
What are foreign
invaders?
• Bacteria are prokaryotic cells. Most life on
Earth is bacterial. Most is not diseasecausing. But immune system must
recognize those that do cause disease
• Viruses are escaped parts of genome or
DNA of different organisms. They cannot
live independent of the cells they escape
from.
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
How do immune cells recognize invaders?
• Invaders are viruses, bacteria and any other substance that is
not part of our body. Remember symbiotic bacteria and other
organisms that normally in and on our body are part of it (we
are more bacterial cells than human cells!)
• During fetal/childhood/adolescent development, immune cells
are exposed to body’s own cells and the proteins that they have
on their surface. This happens mostly in the thymus and bone
marrow. Those immune cell precursors that attack our own
cells are eliminated. Those that recognize other cells continue
to develop as T-cells and B-cells.
• This process is called clonal selection.
• The T-cells and B-cells recognize the foreign proteins that are
on invaders but have been selected so that they don’t
recognize (and try to kill) the body’s own cells
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Antibody editing
by clonal selection
or deletion
• Variety of B-cells produced by
random recombination of genes
for variable regions of antibody
• During B-cell development, certain
clonal lines are eliminated
because their antibodies glom
onto the bodys own antigens
• B-cell production and clonal
selection occurs in bone marrow
during early years of life
• BCRs (B-Cell Receptors or
antibodies recognize
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Antibodies
• Antibodies are the highly variable
proteins that are produced by Bcells in order to recognize the
foreign proteins on the invaders
(called antigens).
• Antibodies are free in the blood
stream. When they are on the
surface of B-cells, they are called
BCRs or B-Cell Receptors. T-cells
also make variable proteins that
can recognize antigens called
TCRs or T-Cell receptors.
• Don’t forget that these proteins
are made by transcription and
translation of certain regions of the
DNA
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
How can each cell have its own different
antibody if they all have the same DNA?
• Nobel Price for Susumu Tonegawa
• DNA is processed and can change as new cells are formed
• Recombining regions of DNA that make the antibody recognition site
produces all the billions of different combinations of antibodies (and BCRs,
TCRs) that recognize any possible invader by the proteins it has on its
Larry M. Frolich, Ph.D.
surface (so we hope!)
Biology Department, Yavapai College
How do immune cells actually get rid of invaders?
• Phagocytes move through blood and lymph and into
connective tissues (part of inflammation response as
cells and fluid move out of capillaries into surround
aleolar tissues--diapedesis)
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
• Then, these macrophages actually engulf and dissolve the invading
microbes.
• There are several different sources or kinds of macrophages
– Langerhans cells in skin
– Phagocytes in blood
– Microglial cells in Central Nervous System
• This is called “non-specific immunity. It does not depend on the antibodies
or B-cells and T-cells. It does not work very well once an infection spreads.
Then we need “specific” immunity based on those specific antibodies that
Larry M. Frolich, Ph.D.
recognize the invader.
Biology Department, Yavapai College
Specific Immune
Response
• This gets complicated.
• In simple terms:
– Antibodies, or BCRs or
TCRs glom onto invaders.
– This calls in cytotoxic Tcells or macrophages and
they kill or engulf the
invading microbe
• See weblinks for animated
graphic of this process
Cytotoxic (“cyto” = cell; “toxic” = kills)
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Mader text view of B-cell and T-cell action
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Blood, Oxygen and Immunity
• Blood everywhere—Circulation
• Oxygen for Cell Respiration
• Immunity
•AIDS
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
HIV and AIDS
HIV—Human Immunodeficiency Virus
AIDS—Acquired Immune Deficiency Syndrome
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
AIDS is caused by HIV virus
How viruses replicate and are transmitted
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
HIV life cycle
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
How is HIV transmitted?
• Virion (loose virus)
doesn’t live long
outside blood
• So transmission is
through blood and
body fluid contact
• Other STD’s
(sexually transmited
diseases) are more
easily transmitted,
but none is as fatal.
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
HIV infects Helper T-cells
• Type 1—stimulate cytotoxic Tcells
• Type 2—stimulate B-cells
• Helper T-cells recognize
antigens, but can do nothing
about it on their own. They
secrete cytokines (such as
interleukin) to direct what kind of
immune response should be
activated.
• For most infections, Helper T’s
are crucial for a robust response.
• Thus, in AIDS, these cells are
killed, as they themselves
present viral antigens and invite
cytotoxic T-cells or macrophages
to ingest them.
• Without the helper T-cells, good
response to most infections
cannot be mounted.
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Typical progress of HIV infection
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Immune Response:
• Complicated because HIV infects cells of
immune system
• HIV doesn’t kill, just lowers body defenses
as T-cell levels drop
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
As immune system function is lost, many unusual and rarely seen
infections begin to take hold
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Epidemiology of spread of AIDS
(population dynamics—Unit IV of Human Biology!)
• Mostly African and
Asian disease
• In U.S., new cases
down throughout
1990’s, now on
rise again—why?
• See web links on
HIV/AIDS
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
REVIEW:
Blood, Oxygen and Immunity
• Blood everywhere—
Circulation
• Oxygen for Cell
Respiration
• Immunity
• AIDS
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Blood is everywhere…how?
• Circulatory system
– Big vessels leave from
pump—heart
– Divide and split to all
major parts of body:
•
•
•
•
•
•
Limbs
Head
Guts
Major organs
Body wall
Skeleton, muscles
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Capillaries—schematic view
•
•
•
•
Very schematic view of what happens in a capillary
Arteries bring blood from heart. Veins take blood to heart.
Network of capillaries really connects artery to vein
Diffusion of needed substances only happens in microscope, thin-walled
capillaries
• See next slide for more realistic view of capillary network or “capillary bed.”
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Why do cells need oxygen?
• Remember Cell Respiration (breaks down glucose to make
high-energy ATP bonds that can be used for cell metabolic
reactions)
– Glycolysis (can happen in absence of oxygen=fermentation)
– Citric acid cycle
– Electron transport chain
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
How does oxygen get into blood?
• Oxygen diffuses into blood in lungs
• In lungs, bronchioles (air tubes) branch and branch, finally
ending in tiny sacs called alveoli.
• Each alveolus is surrounded by capillaries
• Oxygen diffuses across super-thin epithelial tissue of alveolus,
across super-thin epithelial tissue of capillary, across red blood
cell membrane and is held by Hemoglobin protein molecules in
Larry M. Frolich, Ph.D.
red blood cells
Biology Department, Yavapai College
Blood
Cells
• White blood cells fight invading microbes as part of the immune
system
• Include
– Lymphocytes—recognize invaders
– Monocytes and neutrophils—actually consume or engulf microbes
– Basophils—release substances that trigger the other cells.
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
How do immune cells recognize invaders?
• Invaders are viruses, bacteria and any other substance that is
not part of our body. Remember symbiotic bacteria and other
organisms that normally in and on our body are part of it (we
are more bacterial cells than human cells!)
• During fetal/childhood/adolescent development, immune cells
are exposed to body’s own cells and the proteins that they have
on their surface. This happens mostly in the thymus and bone
marrow. Those immune cell precursors that attack our own
cells are eliminated. Those that recognize other cells continue
to develop as T-cells and B-cells.
• This process is called clonal selection.
• The T-cells and B-cells recognize the foreign proteins that are
on invaders but have been selected so that they don’t
recognize (and try to kill) the body’s own cells
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
How do immune cells actually get rid of invaders?
• Phagocytes move through blood and lymph and into
connective tissues (part of inflammation response as
cells and fluid move out of capillaries into surround
aleolar tissues--diapedesis)
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Specific Immune
Response
• This gets complicated.
• In simple terms:
– Antibodies, or BCRs or
TCRs glom onto invaders.
– This calls in cytotoxic Tcells or macrophages and
they kill or engulf the
invading microbe
• See weblinks for animated
graphic of this process
Cytotoxic (“cyto” = cell; “toxic” = kills)
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
HIV life cycle
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
How is HIV transmitted?
• Virion (loose virus)
doesn’t live long
outside blood
• So transmission is
through blood and
body fluid contact
• Other STD’s
(sexually transmited
diseases) are more
easily transmitted,
but none is as fatal.
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Immune Response:
• Complicated because HIV infects cells of
immune system
• HIV doesn’t kill, just lowers body defenses
as T-cell levels drop
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College
Epidemiology of spread of AIDS
(population dynamics—Unit IV of Human Biology!)
• Mostly African and
Asian disease
• In U.S., new cases
down throughout
1990’s, now on
rise again—why?
• See web links on
HIV/AIDS
Larry M. Frolich, Ph.D.
Biology Department, Yavapai College