Download Chapt07 Lecture 13ed Pt 1

Human Biology
Sylvia S. Mader
Michael Windelspecht
Chapter 7
Lymphatic System
and Immunity
Lecture Outline
Part 1
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
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The Lymphatic and Immune
Systems
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Points to ponder
• What is the connection between microbes and
humans?
• What are the parts of the lymphatic system and what
are their functions?
• What are the first and second lines of defense in
nonspecific immunity?
• What is cell-mediated and antibody-mediated
immunity in the third line of defense?
• What are the different types of B cells in these
processes?
• What is active and passive immunity? Be able to
describe how they are different and examples of
each.
• Understand allergic reactions, tissue rejection, and
immune system disorders as problems that the
immune system faces.
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7.1 Microbes, Pathogens, and You
How do microbes and humans
interact?
• Microbes are very abundant, both in the
environment and as inhabitants of __________.
• We use microbes to make many ______ and we
even use them to make_______.
• Microbes are important as ______________ to
recycle nutrients.
• Some microbes cause disease in humans; we
call these pathogens.
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7.1 Microbes, Pathogens, and You
What are microbes?
• Microbes are microscopic organisms and
particles that include
– bacteria,
– viruses,
– prions,
– and other organisms such as fungi,
multicellular parasites, and single-celled
protistans.
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7.1 Microbes, Pathogens, and You
How do the sizes of our cells,
bacteria, and viruses compare?
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Virus
flagella
Figure 7.3
Comparative sizes of
viruses, bacteria, and
eukaryotic cells.
cell
Prokaryotic
cell
Eukaryotic cell
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7.1 Microbes, Pathogens, and You
What are bacteria?
• Bacteria are ___________, prokaryotic
organisms.
• They almost all have a ________.
• Bacteria have DNA in a single chromosome.
• They have ribosomes.
• Some bacteria have accessory rings of DNA
called plasmids.
• Typically, they reproduce by binary fission,
resulting in 2 cells that are identical to the
original cell.
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7.1 Microbes, Pathogens, and You
What are specific structures and
shapes of bacteria?
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Plasmid:
accessory ring of
DNA that often
carries resistant
genes to antibodies
Sex pilus:
elongated, hollow
appendage used
for DNA transfer to
other bacterial cells
Ribosome
Nucleoid
Plasma
membrane
Cell wall
Capsule:
gel-like coating
outside cell wall
Fimbriae:
hair like bristles that
allow adhesion to
surfaces
Flagellum
a.
Figure 7.1 Typical
shapes of bacteria.
b.
SEM 16,000 c.
SEM 3,000 d.
SEM 25,000
b: © Dr. David M. Phillips/Visuals Unlimited; c: © Dr. Dennis Kunkel/Visuals Unlimited; d:© Dr. Gary D. Gaugler/Phototake
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7.1 Microbes, Pathogens, and You
What are viruses?
• Viruses are small, _________ obligate
parasites.
• They must reproduce inside of a ________.
• They are _________ (not composed of cells).
• All viruses have an outer protein coat called a
capsid and nucleic acid (RNA or DNA) inside.
• Some viruses have an envelope.
• Viruses are specific to which cell type they will
attach to and enter.
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7.1 Microbes, Pathogens, and You
What are viruses?
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
TEM 80,000×
Adenovirus: DNA virus with a polyhedral capsid and a fiber
at each corner.
fiber protein
fiber
proteinunit
capsid
DNA
a.
Influenza virus: RNA virus with a spherical capsid surrounded
by an envelope with spikes.
capsid
spikes
20 µm
RNA
envelope
b.
Figure 7.4 Typical virus structures.
a: © Dr. Hans Gelderblom/Visuals Unlimited; b: © K.G. Murti/Visuals Unlimited
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7.1 Microbes, Pathogens, and You
What are prions?
• _______ are infectious protein particles.
• They cause degenerative disease of the
nervous system.
• Normal proteins change their shape.
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7.2 The Lymphatic System
Functions of the lymphatic system
• Lymphatic ___________ absorb excess tissue
fluid and return it to the bloodstream.
• Lymphatic capillaries (lacteals) in the small
intestine absorb fats associated with proteins.
• The lymphatic system works in the production,
maintenance, and distribution of lymphocytes in
the body.
• It helps in defense against ___________.
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7.2 The Lymphatic System
What are the components of the
lymphatic system?
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Tonsil: patches of lymphatic tissue; help to prevent entrance of
pathogens by way of the nose and mouth
Right lymphatic duct:
empties lymph into the
right subclavian vein
Axillary lymph nodes:
located in the underarm region
Thoracic duct: empties
lymph in to the left
subclavian vein
Red bone marrow: site for the origin of all types of blood cells
Thymus: lymphatic tissue where T lymphocytes mature and
learn to tell “self” from “nonself”
Spleen: cleanses the blood of cellular debris and bacteria, while
resident lymphocytes respond to the presence of antigens
tissue
fluid
lymphatic
capillary
tissue cell
Inguinal lymph nodes:
located in the groin region;
cleanse lymph and alert
the immune system to
pathogens
blood
capillary
Figure 7.5 Functions of the lymphatic system components.
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7.2 The Lymphatic System
Lymphatic vessels
• One-way valve system that carries fluid called
lymph
• Made of capillaries, vessels, and ducts
• Function to return tissue fluid (which includes
water, solutes, and cell products) to the
bloodstream
• Larger vessels are similar in structure to _____
and even have valves
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