George Koutsothanasis
Nicole Rebusi
Kate Modica
Ashley Davis
Two types of invertebrate circulation:
Open circulation
Closed circulation
Both have three basic components:
A circulatory fluid (blood), a set of tubes (blood
vessels), and a muscular pump (heart).
Blood is confined to vessels and is distinct from
the interstital fluid.
Materials are exchanged by diffusion between
the blood and the interstital fluid bathing the
cells.
Earthworms, squids, octopuses, and all
vertebrates have closed circulatory systems.
There is no distinction between blood and
hemolymph.
One or more hearts pump the hemolymph into
an interconnected system of sinuses, which are
spaces around organs.
Here chemical exchange occurs between lymph and
body cells.
Often called the cardiovascular system.
The vertebrate heart has one or two atria
The chambers that receive blood returning to the
heart.
One or two ventricles
The chambers that pump blood out of the heart.
Three main kinds:
Arteries- carry blood away from the heart to organs
throughout the body and branch into arterioles- small vessels
that convey blood to capillaries.
Veins-a vessel that returns blood to the heart.
Capillaries- microscopic vessels with very thin, porous walls.
Networks of these vessels, called capillary beds, infiltrate each
tissue.
The human heart is made up of 4
chambers.
The two atria have relatively thin
walls and serve as collection
chambers for blood returning to the
heart.
The ventricles have thicker walls- the
left ventricle pumps blood to all body
organs.
One complete sequence of pumping and filling.
The contraction phase of the cycle is called systole,
and the relaxation phase is diastole.
The volume of blood per minute that the left ventricle
pumps out into the systemic circuit is called cardiac
output.
Cardiac output depends on heart rate and stroke
volume.
Blood delivers nutrients and removes wastes
throughout an animal’s body.
Blood travels over a thousand times faster in the
aorta than in capillaries.
Respiration
•There are many systems in the bodies of animals, each of which serve a
very important purpose without which we wouldn’t exist. The Respiratory
System however serves a purpose that is not too difficult to understand.
The Respiratory System and the Circulatory System are directly linked.
Each of these relies on the other. If one fails, so does the other.
•Respiration is the actual act of gas exchange. Although some may think
this is a simple process, it is important to note that it is much more
complicated.
Gas Exchanging Mechanisms
•There are different types of gas exchanging mechanisms in animals
depending on their natural habitat.
•Fish, because they live in aquatic biomes, adapted organs called gills where
gas exchange takes place.
•Insects, being simpler organisms than mammals, have a tracheal system.
This is a system of tubes that branch throughout the body.
•Mammals and birds have developed organs called lungs. Lungs are different
than tracheal systems in insects in that they are located in one designated in
location and do not branch out to the entire body. That is why animals with
lungs also have a circulatory system.
Gills
•Gills are outfoldings in the bodies of fish. Fish have such a different
respiratory system than land animals because they rely on obtaining their
oxygen from water as opposed to air. Oxygen is much more scarce in water,
especially the deeper you go where there is less phytoplankton producing
oxygen in the water.
•Fishes gills do something called ventilation. Ventilation is the process by
which water enters a fish’s mouth, passes through the pharynx, flows over the
gills and exits the body.
•Fish spend a lot of energy during ventilation because the oxygen per unit of
volume is very low, and they must obtain as much as possible.
•Fishes bodies have developed a mechanism called countercurrent exchange.
This mechanism is very effective and ensures that fish consume the least
amount of energy as possible when they are undergoing respiration. Basically
the blood in a fish’s body flows opposite to the movement of water past the
gills so that the maximum amount of oxygen can be picked up.
Tracheal Systems in
Insects
This is a system of air tubes that branch throughout the body.
Larger tubes called tracheae open to the outside.
All of the body’s cells are within a short distance from the
respiratory medium.
This system suffices for small insects because the trachea
brings in enough oxygen and gets rid of enough carbon dioxide
to support cellular respiration.
Larger insects must ventilate their tracheal systems with
rhythmic body movements.
Mammalian Respiratory
Systems
Mammalian lungs are located in the thoraic cavity and have a spongy
texture. They have a moist epithelium which is the respiratory surface.
In mammals the trachea and the esophagus are right next to each other,
so there must be a system to separate air from food. Whenever food is
swallowed the larynx moves up so that the epiglottis seals with the glottis.
Imagine if your windpipe and esophagus were constantly open
simultaneously?
The vocal cords are located in the larynx. Sound is produce when
muscles in the voice box are tensed. These muscles are stretched so that
they vibrate.
Mammalian Respiratory
Systems
The trachea eventually branches into two bronchi which lead to
each lung.
As soon as we get into the lung, each bronchus separates into
thinner and finer tubes called bronchioles.
At the end of all the bronchioles are clusters of air sacs called
alveoli. It is on the moist epithelial surface of the millions of
alveoli found in lungs that gas exchange occurs.
Breathing Ventilates the
Lungs
The process that ventilates the lungs is called breathing. Breathing
consists of the inhalation and exhalation of air.
Mammals ventilate their lungs through a process called negative
pressure breathing. This basically works like a suction pump that sucks
air into the lungs instead of pushing into the lungs.
Mammalian breathing relies on muscles that change the volume of the rib
cage and chest cavity.
The muscle responsible for changing the chest cavity’s volume is called
the diaphragm. It is a sheet of skeletal muscle which forms the bottom
layer of the chest cavity.
How a Bird Breathes
Ventilation is much more complex in birds than in mammals.
Birds have about nine air sacs separate from the lungs that are
used to trap air.
The air sacs are just pathways to the lungs. The lungs are where
the official gas exchange occurs.
Instead of alveoli, birds have tiny channels called parabronchi.
Air flows through parabronchi in one direction.
Control of Breathing in
Humans
Breathing in humans is a voluntary and involuntary action. Although we can control
the rate at which we breath there are automatic mechanisms that regulate our
breathing.
The breathing control centers are located in two distinct regions of the brain, the
medulla oblongata and the pons.
Secondary control over breathing is exerted by sensors in the aorta and carotid
arteries that monitor oxygen and carbon dioxide concentrations in the blood as well
as blood pH.
The Role of Partial Pressure
Gradients
Diffusion of a gas depends on differences in a quantity called partial pressure.
A gas always diffuses from an area of higher to lower pressure.
Blood that arrives at the lungs via the pulmonary arteries has a lower pressure of
oxygen and higher pressure of carbon dioxide.
Respiratory Pigments
Since oxygen has a low solubility in water a problem is posed to
animals that rely on the circulatory system to deliver oxygen.
Most animals transport most of their oxygen bound to certain
proteins called respiratory proteins instead of in dissolved form.
Respiration Activity
1.
The part of an animal’s body where gases are exchanged with the surrounding environment is
called the ________________.
2.
_______________ is the mechanism through which blood flows in the opposite direction of blood
flow.
3.
The _______________ is made up if air tubes that branch through the entire body.
4.
These sites of gas exchange called ________ are restricted to one location.
5.
The ________ moves upward in order to tip the epiglottis over the glottis.
6.
Exhaled air rushes by a pair of ____________ in the larynx.
7.
From the larynx, air passes into the _________.
8.
The tinies bronchioles dead-end as a cluster of air sacs called ________.
Activity Answers
1.
Respiratory Surface
2.
Countercurrent Exchange
3.
Tracheal System
4.
Lungs
5.
Larynx
6.
Vocal Cords
7.
Trachea
8.
Alveoli
The Immune System
The body has two mechanisms in defending itself:
Nonspecific defense mechanism and specific defense
mechanism. It is then subdivided into three lines of
defenses.
Nonspecific Defense Mechanism
First line of defense.
Is external and consists of epithelial tissues that cover and line our bodies and the
secretions they produce.
Examples are skin and mucous membrane.
Key terms:
Antimicrobial proteins: function in nonspecific defense either by attacking microbes directly
or by impeding their production.
Complement System: a group of at least 20 blood proteins that cooperate with other
defense mechanism. It amplifies the inflammatory response, enhances phagocytosis,
and directly lyses pathogens.
Second line of defense
Is internal.
It is triggered by chemical signals and involves phagocytic cells and antimicrobial protein that
indiscriminately attacks invaders that penetrates the body’s outer barriers.
Inflammation is a sign of this defense.
Includes phagocytic white blood cells, antimicrobial proteins, and the inflammatory response.
Key Terms:
Phagocytosis: the injection of invading organisms by certain types of white cells.
Neutrophills: white blood cells; cells damaged by invading microbes release chemical signals that attract
neutrophils from the blood. They enter infected tissue,engulfing and destroying microbes there.
Macrophages: are the largest phagocytic cells. They engulf a microbe in vacuole that fuses with a
lysosome.
Natural Killer (NK) cells: destroy virus infected body cells
Inflammatory response: a line of defense
triggered by penetration of skin or mucous
membranes in which small blood vessels in the
vicinity of an injury dilate and become leakier,
enhancing filtration of leukocytes.
How is the inflammatory response initiated?
Chemical signals such as histamine are
released by cells of the body in response to
tissue injury.
NK cells
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Specific Defense Mechanism
Third line of defense
Known as The Immune System; it works
simultaneously with the second line of defense,
but it responds in a specific way to particular
microorganisms, aberrant body cells, toxins, and
other substances marked by foreign molecules.
Includes the production of proteins called
antibodies and involves a diverse group of blood
cells called lymphocytes.
Lymphocytes
B lymphocyte (B Cell):a type of lymphocyte that develops in the bone marrow
and later produces antibodies.
T lymphocyte (T Cell): a type of lymphocyte responsible for cell-mediated
immunity that differentiates under the influences of the thymus.
Both B Cell and T Cell circulate throughout the blood and lymphocytes and are
concentrated in the spleen, lymph nodes, and other lymphatic tissues.
Specific. Why?
Because lymphocytes recognize and respond to
particular microbes and foreign molecules.
How?
T cell
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•Antigen: a foreign macromolecule that does not belong to the host organism and that
elicits an immune response.
•Antibody: an antigen-binding immunoglobulin, produced by B Cells, that functions as
the effector in an immune response
Antigen receptors:
transmembrane
versions of antibody
molecules that B Cells
and T Cells use to
recognize specific
agents.
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Effector Cell: a muscle cell or gland cell that performs the body’s responses to stimuli.
Memory Cells: long-lived cells bearing receptors for the same antigen.
Acquired Immunity: highly specific; develops only
Immunity
after the body is exposed to inducing agents
Innate Immunity: nonspecific; present before any
exposure to pathogens and is effective from the
time of birth.
Word Bank
Activity 1 : Immune
System
Effector Cells
Macrophages
Histamine
Chemokines
Neutrophils
Cytotoxic
Inflammatory response
Memory cells
3
Complete Sentences
1. ___________ are the largest phagocytic cells that
extend long pseudopodia that can attach to
polysaccharides on a microbes surface.
2. Damage to tissue by a physical injury or by the entry
of microorganisms triggers a localized ___________,
increasing the local blood supply.
3. Attract phagocytes to an area and is secreted by
endothelial cells blood vessels and monocytes, are
called__________ molecules.
4. ____________ are short lived cells that combat the
same antigen.
5. Long lived cells bearing receptors specific for the same
antigen._____________.
6. How many lines of defense are there ___.
7. Cells damaged by invading microbes release chemical
signals that attract _________from the blood.
8.________ is produced by circulating leukocytes .
9._______T lymphocytes kill cancer cells and cells infected by
viruses.
Activity 2: Immune System
True or False
1.Lymphocytes are a part of the second line of defense.
2.Anti-microbal proteins are the first line of defense.
3.B cells are a type of lymphocyte.
4. Natural killers do not attack o the viruses membrane and cause
the cell to lyse.
5.Inflammatory response is initiated by chemical signals.
6.Interestrial fluid is found in blood vessels.
7.Only B cells circulate throughout the blood.
Answer
Activity1:
1. Macrophages
2. Inflammatory response
3. Chemokines
4. Effector cells
5. Memory cells
6. 3
7. Neutrophils
Activity 2
1.False
2.False
3.True
4.False
5.True
6.False
7.False
8.False
9.True
10.True