Part 1 - Get a Lab Appointment and Install Software:
Set up an Account on the Scheduler (FIRST TIME USING NANSLO):
Find the email from your instructor with the URL (link) to sign up at the scheduler.
Set up your scheduling system account and schedule your lab appointment.
NOTE: You cannot make an appointment until two weeks prior to the start date of this lab assignment.
You can get your username and password from your email to schedule within this time frame.
Install the Citrix software: – go to http://receiver.citrix.com and click
download > accept > run > install (FIRST TIME USING NANSLO).
You only have to do this ONCE. Do NOT open it after installing. It will work automatically when you go
to your lab. (more info at
http://www.wiche.edu/info/nanslo/creative_science/Installing_Citrix_Receiver_Program.pdf)
Scheduling Additional Lab Appointments:
Get your scheduler account username and password from your email.
Go to the URL (link) given to you by your instructor and set up your appointment.
(more info at http://www.wiche.edu/nanslo/creative-science-solutions/students-scheduling-labs)
Changing Your Scheduled Lab Appointment:
Get your scheduler account username and password from your email. Go to http://scheduler.nanslo.org
and select the “I am a student” button. Log in to go to the student dashboard and modify your
appointment time. (more info at http://www.wiche.edu/nanslo/creative-science-solutions/studentsscheduling-labs)
Part 2 – Before Lab Day:
Read your lab experiment background and procedure below, pages 1-22.
Submit your completed Pre-Lab 1-5 Exercises (pages 4-15) per your faculty’s instructions.
Watch the Microscope Control Panel Video Tutorial
http://www.wiche.edu/nanslo/lab-tutorials#microscope
Part 3 – Lab Day
Log in to your lab session – 2 options:
1)Retrieve your email from the scheduler with your appointment info or
2) Log in to the student dashboard and join your session by going to http://scheduler.nanslo.org
NOTE: You cannot log in to your session before the date and start time of your appointment. Use
Internet Explorer or Firefox.
Click on the yellow button on the bottom of the screen and follow the instructions to talk to your lab
partners and the lab tech.
Remote Lab Activity
SUBJECT SEMESTER: ____________
TITLE OF LAB: Parasitology
Lab format: This lab is a remote lab activity.
Relationship to theory (if appropriate): In this lab you will learn to identify the several life
stages and differences in appearance of several reprehensive parasites.
Instructions for Instructors: This protocol is written under an open source CC BY license. You
may use the procedure as is or modify as necessary for your class. Be sure to let your students
know if they should complete optional exercises in this lab procedure as lab technicians will not
know if you want your students to complete optional exercises.
Instructions for Students: Read the complete laboratory procedure before coming to lab.
Under the experimental sections, complete all pre-lab materials before logging on to the
remote lab. Complete data collection sections during your online period, and answer questions
in analysis sections after your online period. Your instructor will let you know if you are
required to complete any optional exercises in this lab.
Remote Resources: Primary – Microscope, Secondary – Introduction to Parasitology slide set.
CONTENTS FOR THIS NANSLO LAB ACTIVITY:
Learning Objectives........................................................................................................
Background Information ...............................................................................................
Pre-lab Exercise 1: Microscopic Examination of Giardia Lamblia
Cysts and Trophozoites ..........................................................................................
Pre-lab 1 Question .......................................................................................................
Pre-lab Exercise 2: Microscopic Examination of Entamoeba Granulosus Cysts ...........
Pre-lab 2 Question .......................................................................................................
Pre-lab Exercise 3: Microscopic Examination of Taenia Saginata Eggs .......................
Pre-lab 3 Question .......................................................................................................
Pre-lab Exercise 4: Microscopic Examination of Plamodium Falciparum Rings
and Plasmodium Vivax All Stages ...........................................................................
Pre-lab 4 Question .......................................................................................................
Pre-lab Exercise 5: Microscopic Examination of Ascaris Lumbricoides Eggs ...............
Pre-lab 5 Question .......................................................................................................
Equipment .....................................................................................................................
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CONTENTS FOR THIS NANSLO LAB ACTIVITY – CONT’D
Preparing for this NANSLO Lab Activity ........................................................................
Experimental Procedure ...............................................................................................
Exercise 1: Microscopic Examination of Giardia Lamblia Cysts and Trophozoites ......
Exercise 2: Microscopic Examination of Entamoeba Granulosus Cysts .......................
Exercise 3: Microscopic Examination of Taenia Saginata Eggs ....................................
Exercise 4: Microscopic Examination of Plamodium Falciparum Rings and
Plasmodium Vivax All Stages ...................................................................................
Exercise 5: Microscopic Examination of Ascaris Lumbricoides Eggs ...........................
Summary Questions ......................................................................................................
Creative Commons Licensing ........................................................................................
U.S. Department of Labor Information .........................................................................
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LEARNING OBJECTIVES:
After completing this laboratory experiment, you should be able to do the following things:
1. Identify and distinguish between the different kinds of intestinal parasites: Giardia
lamblia, Entamoeba granulosus, Taenia saginata, Plasmodium falciparum, Plasmodium
vivax, and Ascaris lumbricoides.
2. Identify and distinguish between the different larval stages of certain parasites.
3. Identify and distinguish between cysts, eggs, and trophozoites.
4. Measure the relative size of cysts and eggs and provide a comparison between them.
BACKGROUND INFORMATION:
Worldwide, parasitic diseases constitute a major health problem in several developed and
developing countries. Each year, the World Health Organization (WHO) publishes reports
relevant to the prevalence of parasitic diseases across the World. The lack of sanitation, poor
education, and poverty has led to the increase of their prevalence in developing countries. The
severity of human parasitic diseases ranges from minimal to life-threatening such as the case of
malaria and schistosomiasis. Certain infections lead to nutritional loss such as the case of the
Ascaris infection common among children in developing countries.
Parasitology is the study of animal and plant parasitism as a biological phenomenon. Parasites
occur in virtually all major animal groups and in many plant groups with hosts as varied as the
parasites themselves.
Parasitism is a type of association between two species where one benefits and the other is
harmed.
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A parasite is an organism that lives on or in a host and gets its food from or at the expense of its
host. Parasites can cause disease in humans. Some parasitic diseases are easily treated and
some are not. The burden of these diseases often rests on communities in the tropics and
subtropics, but parasitic infections also affect people in developed countries. Throughout
evolution, parasites have developed the ability to grow either inside or on their host cells and
require more than one host as part of their life cycle.
Certain parasites are transmitted via direct contact from a carrier. Others require a biological
vector where the parasite completes part of its life cycle before being transmitted to another
host. Several parasites have the ability to produce either cysts or eggs. Cysts are forms that are
resistant to the environment allowing the parasites to survive during unfavorable conditions.
Eggs are also resistant to environmental changes but they get their protection from a thick
protective coat. Studying life cycles of several human parasites has led to an advance in control
and prevention of the infections, but we need to also recognize that some parasites along with
their vectors have developed resistance to certain drugs and chemicals making it difficult to
completely eradicate certain parasitic infections.
Numerous parasites can be transmitted by food including many protozoa and helminthes. In
the United States, the most common food borne parasites are protozoa such as Cryptosporidium
spp., Giardia intestinalis, Cyclospora cayetanensis, and Toxoplasma gondii; roundworms such as
Trichinella spp. and Anisakis spp.; and tapeworms such as Diphyllobothrium spp. and Taenia spp.
(Click on the italicized words to get more information about each type of parasite). Many of
these organisms can also be transmitted by water, soil, or person-to-person contact.
Occasionally in the U.S., but often in developing countries, a wide variety of helminthic
roundworms, tapeworms, and flukes are transmitted in foods such as:
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undercooked fish, crabs, and mollusks;
undercooked meat; raw aquatic plants such as watercress; and
raw vegetables that have been contaminated by human or animal feces.
Some foods are contaminated by food service workers who practice poor hygiene or who work
in unsanitary facilities.
Symptoms of food borne parasitic infections vary greatly depending on the type of parasite.
Protozoa such as Cryptosporidium spp., Giardia intestinalis, and Cyclospora cayetanensis most
commonly cause diarrhea and other gastrointestinal symptoms. Helminthic infections can
cause abdominal pain, diarrhea, muscle pain, cough, skin lesions, malnutrition, weight loss,
neurological and many other symptoms depending on the particular organism and burden of
infection. Treatment is available for most of the food borne parasitic organisms.
The human body can be infected by several prokaryotic and eukaryotic parasites. In this lab you
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will learn to identify the different phases of the life cycle of several represented parasites that
infect humans.
References:
http://www.britannica.com/EBchecked/topic/443269/parasitology
http://www.cdc.gov/parasites/food.html
PRE-LAB EXERCISE 1: Microscopic Examination of Giardia Lamblia
Cysts and Trophozoites
Giardiasis is a diarrheal illness caused by a microscopic parasite Giardia intestinalis (also known
as Giardia lamblia, or Giardia duodenalis) found on surfaces or in soil, food, or water that has
been contaminated with feces from infected humans or animals. Giardia intestinalis is a
protozoan flagellate (Diplomonadida) which is protected by an outer shell that allows it to
survive outside the body for long periods of time and makes it tolerant to chlorine disinfection.
While the parasite can be spread in different ways, water (drinking water and recreational
water) is the most common method of transmission. The Giardia life cycle has several forms.
The two we are most interested in are cysts and trophozoites.
Figure 1: Shows three microscopic slides. The one on the left is a G. intestinalis trophozoites
in Kohn stain. The center one is a G. intestinalis cyst stained with trichrome. The one on the
right is a G. intestinalis in vitro culture, from a quality control slide.
http://www.cdc.gov/parasites/giardia/
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Life Cycle:
Figure 2: Life cycle of Giardiasis in a human.
Cysts are a resistant form and are responsible for transmission of giardiasis. Both cysts and
trophozoites can be found in the feces (diagnostic stages) . The cysts are hardy and can
survive several months in cold water. Infection occurs by the ingestion of cysts in contaminated
water, food, or by the fecal-oral route (hands or fomites) . In the small intestine, excystation
releases trophozoites (each cyst produces two trophozoites) . Trophozoites multiply by
longitudinal binary fission, remaining in the lumen of the proximal small bowel where they can
be free or attached to the mucosa by a ventral sucking disk . Encystation occurs as the
parasites transit toward the colon. The cyst is the stage found most commonly in nondiarrheal
feces . Because the cysts are infectious when passed in the stool or shortly afterward,
person-to-person transmission is possible. While animals are infected with Giardia, their
importance as a reservoir is unclear.
In this lab exercise you will observe and measure the relative size of Giardia lamblia cysts.
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References:
http://www.cdc.gov/parasites/giardia/biology.html
PRE-LAB 1 QUESTION:
1. What kind of shape do you think the Giardia lamblia cysts will have?
PRE-LAB EXERCISE 2: Microscopic Examination of Entamoeba Granulosus Cysts
Amebiasis is a disease caused by the parasite Entamoeba histolytica. It can affect anyone,
although it is more common in people who live in tropical areas with poor sanitary conditions.
Entamoeba histolytica is well recognized as a pathogenic ameba associated with intestinal and
extraintestinal infections.
Life Cycle:
Figure 3: Life cycle of Entamoeba Granulosus Cysts in a human.
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Just like Giardia lamblia the cysts and trophozoites of Entamoeba histolytica are passed in feces
. Cysts are typically found in formed stool, whereas trophozoites are typically found in
diarrheal stool. Infection by Entamoeba histolytica occurs by ingestion of mature cysts in
fecally contaminated food, water, or hands. Excystation occurs in the small intestine and
trophozoites are released, which migrate to the large intestine. The trophozoites multiply by
binary fission and produce cysts , and both stages are passed in the feces . Because of the
protection conferred by their walls, the cysts can survive days to weeks in the external
environment and are responsible for transmission. Trophozoites passed in the stool are rapidly
destroyed once outside the body, and if ingested would not survive exposure to the gastric
environment. In many cases, the trophozoites remain confined to the intestinal lumen ( :
noninvasive infection) of individuals who are asymptomatic carriers, passing cysts in their stool.
In some patients, the trophozoites invade the intestinal mucosa ( : intestinal disease), or,
through the bloodstream, extraintestinal sites such as the liver, brain, and lungs ( :
extraintestinal disease) with resultant pathologic manifestations. It has been established that
the invasive and noninvasive forms represent two separate species, respectively E. histolytica
and E. dispar. These two species are morphologically indistinguishable unless E. histolytica is
observed with ingested red blood cells (erythrophagocystosis). Transmission can also occur
through exposure to fecal matter during sexual contact (in which case not only cysts, but also
trophozoites could prove infective).
References:
http://www.cdc.gov/parasites/amebiasis/biology.html
In this lab exercise you will measure the relative size of Entamoeba histolytica cysts and compare
them with the ones produced by Giardia lamblia.
PRE-LAB 2 QUESTION:
1. Do you predict the size of Entamoeba histolytica cysts to be smaller, bigger or the same
as the Giardia lamblia ones?
2. Rewrite your answer to question one in the form of an If … Then … hypothesis.
PRE-LAB EXERCISE 3: Microscopic Examination of Taenia Saginata Eggs
Taeniasis in humans is a parasitic infection caused by the tapeworm species Taenia saginata
(beef tapeworm), Taenia solium (pork tapeworm), and Taenia asiatica (Asian tapeworm).
Humans can become infected with these tapeworms by eating raw or undercooked beef (T.
saginata) or pork (T. solium and T. asiatica). People with taeniasis may not know they have a
tapeworm infection because symptoms are usually mild or nonexistent.
Humans pass the tapeworm segments and/or eggs in feces and contaminate the soil in areas
where sanitation is poor. Taenia eggs can survive in a moist environment and remain infective
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for days to months. Cows and pigs become infected after feeding in areas that are
contaminated with Taenia eggs from human feces. Once inside the cow or pig, the Taenia eggs
hatch in the animal’s intestine and migrate to striated muscle to develop into cysticerci, causing
a disease known as cysticercosis. Cysticerci can survive for several years in animal muscle.
Humans become infected with tapeworms when they eat raw or undercooked beef or pork
containing infective cysticerci. Once inside humans, Taenia cysticerci migrate to the small
intestine and mature to adult tapeworms which produce segments and eggs that are passed in
feces. Infection with T. solium tapeworms can result in human cysticercosis which can be a very
serious disease that can cause seizures and muscle or eye damage.
Life Cycle:
Figure 4: Life cyle of Taeniasis in a human.
Taeniasis is the infection of humans with the adult tapeworm of Taenia saginata or Taenia
solium. Humans are the only definitive hosts for T. saginata and T. solium. Eggs or gravid
proglottids are passed with feces ; the eggs can survive for days to months in the
environment. Cattle (T. saginata) and pigs (T. solium) become infected by ingesting vegetation
contaminated with eggs or gravid proglottids . In the animal's intestine, the oncospheres
hatch , invade the intestinal wall, and migrate to the striated muscles, where they develop
into cysticerci. A cysticercus can survive for several years in the animal. Humans become
infected by ingesting raw or undercooked infected meat . In the human intestine, the
cysticercus develops over two months into an adult tapeworm which can survive for years. The
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adult tapeworms attach to the small intestine by their scolex and reside in the small intestine
. Length of adult worms is usually 5 m or less for T. saginata (however it may reach up to 25
m) and 2 to 7 m for T. solium. The adults produce proglottids which mature become gravid,
detach from the tapeworm, and migrate to the anus or are passed in the stool (approximately 6
per day). T. saginata adults usually have 1,000 to 2,000 proglottids, while T. solium adults have
an average of 1,000 proglottids. The eggs contained in the gravid proglottids are released after
the proglottids are passed with the feces. T. saginata may produce up to 100,000 and T. solium
may produce 50,000 eggs per proglottid respectively.
In this lab exercise you will observe and measure the relative size of Taenia saginata eggs and
compare it to the size of Entamoeba histolytica cysts measured in the previous exercise.
References:
http://www.cdc.gov/parasites/taeniasis/biology.html
PRE-LAB 3 QUESTIONS:
1. Do you predict the size of normal Taenia saginata eggs to be smaller, bigger or the same
as Entamoeba granulosus cysts?
2. Rewrite your answer to question one in the form of an If … Then … hypothesis.
PRE-LAB EXERCISE 4: Microscopic Examination of Plamodium Falciparum Rings
and Plasmodium Vivax All Stages
Malaria is a mosquito-borne disease caused by a Plasmodium parasite that can be spread to
humans. Diseases that are spread between animals and humans are said to be zoonotic.
Malaria is a serious and sometimes fatal disease that commonly infects a certain type of
mosquito which feeds on humans. People who get malaria are typically very sick with high
fevers, shaking chills, and flu-like illness. Although malaria can be a deadly disease, illness and
death from malaria can usually be prevented. Left untreated, they may develop severe
complications and die. In 2010 an estimated 219 million cases of malaria occurred worldwide
and 660,000 people died, most (91%) in the African Region. About 1,500 cases of malaria are
diagnosed in the United States each year. The vast majority of cases in the United States are in
travelers and immigrants returning from countries where malaria transmission occurs, many
from sub-Saharan Africa and South Asia.
Malaria parasites are micro-organisms that belong to the genus Plasmodium. There are more
than 100 species of Plasmodium, which can infect many animal species such as reptiles, birds,
and various mammals. Four species of Plasmodium have long been recognized to infect humans
in nature. In addition there is one species that naturally infects macaques which has recently
been recognized to be a cause of zoonotic malaria in humans. (There are some additional
species which can, exceptionally or under experimental conditions, infect humans).
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The human naturally infecting species are:
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P. falciparum is found worldwide in tropical and subtropical areas. It is estimated that
every year approximately 1 million people are killed by P. falciparum, especially in Africa
where this species predominates. P. falciparum can cause severe malaria because it
multiples rapidly in the blood and can thus cause severe blood loss (anemia). In
addition, the parasites can clog small blood vessels. When this occurs in the brain,
cerebral malaria results, a complication that can be fatal.
P. vivax is found mostly in Asia, Latin America, and in some parts of Africa. Because of
the population densities, especially in Asia, it is probably the most prevalent human
malaria parasite. P. vivax (as well as P. ovale) has dormant liver stages ("hypnozoites")
that can activate and invade the blood ("relapse") several months or years after the
infecting mosquito bite.
P. ovale is found mostly in Africa (especially West Africa) and the islands of the western
Pacific. It is biologically and morphologically very similar to P. vivax. However, differently
from P. vivax, it can infect individuals who are negative for the Duffy blood group, which
is the case for many residents of sub-Saharan Africa. This explains the greater
prevalence of P. ovale (rather than P. vivax) in most of Africa.
P. malariae, found worldwide is the only human malaria parasite species that has a
quartan cycle (three-day cycle). (The three other species have a tertian, two-day cycle.)
If untreated, P. malariae causes a long-lasting, chronic infection that in some cases can
last a lifetime. In some chronically infected patients P. malariae can cause serious
complications such as the nephritic syndrome.
P. knowlesi is found throughout Southeast Asia as a natural pathogen of long-tailed and
pig-tailed macaques. It has recently been shown to be a significant cause of zoonotic
malaria in that region, particularly in Malaysia. P. knowlesi has a 24-hour replication
cycle and so can rapidly progress from an uncomplicated to a severe infection; fatal
cases have been reported.
The natural life cycle of malaria involves the malaria parasites infecting successively two types
of hosts: humans and female Anopheles mosquitoes. In humans, the parasites grow and
multiply first in the liver cells and then in the red cells of the blood. In the blood, successive
broods of parasites grow inside the red cells and destroy them, releasing daughter parasites
("merozoites") that continue the cycle by invading other red cells. The blood stage parasites are
those that cause the symptoms of malaria. When certain forms of blood stage parasites
("gametocytes") are picked up by a female Anopheles mosquito (see Figure below) during a
blood meal, they start another, different cycle of growth and multiplication in the mosquito.
After 10-18 days, the parasites are found (as "sporozoites") in the mosquito's salivary glands.
When the Anopheles mosquito takes a blood meal on another human, the sporozoites are
injected with the mosquito's saliva and start another human infection when they parasitize the
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liver cells. Thus the mosquito carries the disease from one human to another (acting as a
"vector"). Differently from the human host, the mosquito vector does not suffer from the
presence of the parasites.
Life Cycle:
Figure 5: Life cycle of Malaria Parasite.
The malaria parasite life cycle involves two hosts. During a blood meal, a malaria-infected
female Anopheles mosquito inoculates sporozoites into the human host . Sporozoites infect
liver cells and mature into schizonts , which rupture and release merozoites . (Of note, in
P. vivax and P. ovale a dormant stage [hypnozoites] can persist in the liver and cause relapses
by invading the bloodstream weeks, or even years later.) After this initial replication in the liver
(exo-erythrocytic schizogony ), the parasites undergo asexual multiplication in the
erythrocytes (erythrocytic schizogony ). Merozoites infect red blood cells . The ring stage
trophozoites mature into schizonts, which rupture releasing merozoites . Some parasites
differentiate into sexual erythrocytic stages (gametocytes) . Blood stage parasites are
responsible for the clinical manifestations of the disease. The gametocytes, male
(microgametocytes) and female (macrogametocytes) are ingested by an Anopheles mosquito
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during a blood meal . The parasites’ multiplication in the mosquito is known as the sporogonic
cycle . While in the mosquito's stomach, the microgametes penetrate the macrogametes
generating zygotes . The zygotes in turn become motile and elongated (ookinetes) which
invade the midgut wall of the mosquito where they develop into oocysts . The oocysts grow,
rupture, and release sporozoites , which make their way to the mosquito's salivary glands.
Inoculation of the sporozoites into a new human host perpetuates the malaria life cycle.
Figure 6: Anopheles Freeborni Mosquito Pumping Blood
http://www.cdc.gov/malaria/about/biology/mosquitoes/freeborni_large.html
References:
http://www.cdc.gov/dpdx/malaria/
http://www.cdc.gov/malaria/diagnosis_treatment/diagnosis.html
http://www.cdc.gov/malaria/about/biology/
http://www.cdc.gov/malaria/about/biology/parasites.html
In this lab exercise you will observe and measure the diameter of Plasmodium falciparum rings
and compare it with the one of Plasmodium vivax rings.
PRE-LAB 4 QUESTION:
1. In this lab you will examine the ring stage of two different species of the Plasmodium
parasite. Do you expect to see a difference in the size of the rings? Explain your
reasoning.
PRE-LAB EXERCISE 5: Microscopic Examination of Ascaris Lumbricoides Eggs
Ascariasis: An estimated 807-1,221 million people in the world are infected with Ascaris
lumbricoides (sometimes called just "Ascaris"). Ascaris, hookworm, and whipworm are known
as soil-transmitted helminths (parasitic worms). Together, they account for a major burden of
disease worldwide. Ascariasis is now uncommon in the United States.
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Ascaris lives in the intestine and Ascaris eggs are passed in the feces of infected persons. If the
infected person defecates outside (near bushes, in a garden, or field) or if the feces of an
infected person are used as fertilizer, eggs are deposited on soil. They can then mature into a
form that is infective. Ascariasis is caused by ingesting eggs. This can happen when hands or
fingers that have contaminated dirt on them are put in the mouth or by consuming vegetables
or fruits that have not been carefully cooked, washed or peeled.
People infected with Ascaris often show no symptoms. If symptoms do occur they can be light
and include abdominal discomfort. Heavy infections can cause intestinal blockage and impair
growth in children. Other symptoms such as cough are due to migration of the worms through
the body. Ascariasis is treatable with medication prescribed by your health care provider.
Figure 6: Left/Right: Fertilized eggs of A. lumbricoides in unstained wet mounts of stool.
Center: Adult female A. lumbricoides
http://www.cdc.gov/parasites/ascariasis/
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Life Cycle:
Figure 7: Life cycle of the Ascaris lumbricoides.
Adult worms live in the lumen of the small intestine. A female may produce approximately
200,000 eggs per day which are passed with the feces . Unfertilized eggs may be ingested but
are not infective. Fertile eggs embryonate and become infective after 18 days to several weeks
, depending on the environmental conditions (optimum: moist, warm, shaded soil). After
infective eggs are swallowed , the larvae hatch , invade the intestinal mucosa, and are
carried via the portal, then systemic circulation to the lungs . The larvae mature further in the
lungs (10 to 14 days), penetrate the alveolar walls, ascend the bronchial tree to the throat, and
are swallowed . Upon reaching the small intestine, they develop into adult worms .
Between 2 and 3 months are required from ingestion of the infective eggs to oviposition by the
adult female. Adult worms can live 1 to 2 years.
References:
http://www.cdc.gov/parasites/ascariasis/biology.html
http://www.cdc.gov/parasites/ascariasis/
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PRE-LAB 5 QUESTION:
1. Several of the parasites you are examining in this lab use cysts to protect themselves
from the environment. The round worm Ascaris lumbricoides uses eggs to accomplish
the same functions what differences and similarities do you expect to see between eggs
and cysts.
In this lab exercise you will observe Ascaris lumbricoides eggs.
EQUIPMENT:
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Paper
Pencil/pen
Slides
o Giardia lamblia Cysts
o Giardia lamblia Trophozoites
o Entamoeba histolytica cysts
o Taenia saginata eggs
o Plasmodium falciparum rings
o Plasmodium vivax all stages
o Ascaris lumbricoides eggs
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Computer with Internet access for the remote laboratory and for data analysis
PREPARING FOR THIS NANSLO LAB ACTIVITY:
Read and understand the information below before you proceed with the lab!
Scheduling an Appointment Using the NANSLO Scheduling System
Your instructor has reserved a block of time through the NANSLO Scheduling System for you to
complete this activity. For more information on how to set up a time to access this NANSLO lab
activity, see www.wiche.edu/nanslo/scheduling-software.
Students Accessing a NANSLO Lab Activity for the First Time
For those accessing a NANSLO laboratory for the first time, you may need to install software on
your computer to access the NANSLO lab activity. Use this link for detailed instructions on
steps to complete prior to accessing your assigned NANSLO lab activity –
www.wiche.edu/nanslo/lab-tutorials.
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Video Tutorial for RWSL: A short video demonstrating how to use the Remote Web-based
Science Lab (RWSL) control panel for the air track can be viewed at
http://www.wiche.edu/nanslo/lab-tutorials#microscope.
NOTE: Disregard the conference number in this video tutorial.
AS SOON AS YOU CONNECT TO THE RWSL CONTROL PANEL: Click on the yellow button at the
bottom of the screen (you may need to scroll down to see it). Follow the directions on the pop
up window to join the voice conference and talk to your group and the Lab Technician.
EXPERIMENTAL PROCEDURE
Once you have logged on to the remote lab system, you will perform the following laboratory
procedures. See Preparing for the Microscope NANSLO Lab Activity below.
EXERCISE 1: Microscopic Examination of Giardia Lamblia Cysts and Trophozoites
Data Collection:
1. Select the Giardia lamblia cysts slide (Slide Cassette 3: #1) from the microscope
interface. Using the 10X objective, identify the cysts and bring them into focus.
2. Carefully work your way through all the objectives focusing with each one until you
reach the 60X objective and capture an image of Giardia lamblia cysts. Insert the image
below.
3. Select the Giardia lamblia trophozoites slide (Slide Cassette 3: #2) from the microscope
interface. Using the 10X objective, identify the trophozoites and bring them in to focus.
4. Carefully work your way through all the objectives focusing with each one until you
reach the 60X objective and capture an image of Giardia lamblia trophozoites. Insert
your images below.
Analysis:
5. Using your image from step 2, label the cysts. Insert your image below.
6. Describe the shape of the cysts.
7. Next we are going to measure the size of the cysts. To determine the size of the cysts,
we are going to use the ratio method. In order to do this, you will need one piece of
information which is the width of your field of view. On our microscopes, the field of
view is 305µm at 40X magnification and 205µm at 60X magnification.
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8. Using the image in Figure 1 as an example, we can see that the total width of the field of
view is 13.6 cm or 136 mm (Image A). The cell (Gray) is 3.7 cm or 37mm (Image B).
Figure 8: Measurements
9. Dividing 37mm/136mm = 0.272 which we multiply by the total length of the field of
view so (60x (0.272 * 205µm = 55.77 µm) rounded for significant figures gives us a cell
size of 56µm.
10. Using your image from step 4, label the trophozoites, the nuclei and the flagella. Insert
your image below.
11. Describe the shape of the throphozoites.
EXERCISE 2: Microscopic Examination of Entamoeba Granulosus Cysts
Data Collection:
1. Select the Entamoeba histolytica cysts slide (slide Cassette 3: #10) from the slide loader.
Using the 10X objective identify the cysts and bring them into focus.
2. Carefully work your way through all the objectives focusing with each one until you
reach the 60X objective and capture an image. Insert your image of Entamoeba
histolytica cysts below.
Analysis:
3. Using your picture from step 2, label the cysts. Inset your labeled image below.
4. Utilizing the method from Exercise 1, determine the length of the Entamoeba histolytica
cysts.
5. Based on your observation and measurement, describe the difference between shape of
Giardia lamblia cysts and Entamoeba histolytica cysts
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6. Are your results in correlation with what you have predicted earlier?
7. Rewrite your hypothesis to take into account the new information you have learned in
this exercise.
8. What is the impact of drinking water contaminated with cysts on the digestive system
and the overall function of the human body?
EXERCISE 3: Microscopic Examination of Taenia Saginata Eggs
Data Collection:
1. Select the Taenia saginata eggs slide (Slide Cassette 3: #5) from the slide loader. Using
the 10X objective identify Taenia saginata eggs and bring them into focus.
2. Carefully work your way through all the objectives focusing with each one until you
reach the 60X objective and capture an image. Insert your image of Taenia saginata
eggs below.
Analysis:
3. Utilizing the image from step 2, label the eggs. Insert the labeled image below.
4. Utilizing the method from Exercise 1, determine the diameter of Taenia saginata eggs
5. Based on your observation and measurement, describe the difference between the size
of Taenia saginata eggs and Entamoeba granulosus cysts?
6. Are your results in correlation with what you have predicted earlier?
7. Rewrite your hypothesis to take into account the new information you have learned in
this exercise.
8. What structure is more resistant the cyst or the egg? Explain your answer.
EXERCISE 4: Microscopic Examination of Plamodium Falciparum Rings and
Plasmodium Vivax All Stages
Data Collection:
1. Select the Plasmodium falciparum rings slide (Slide Cassette 3: #16) from the slide
loader. Using the 10X objective identify the Plasmodium falciparum rings and bring
them into focus.
2. Carefully work your way through all the objectives focusing with each one until you
reach the 60X objective and capture an image. Insert your image Plasmodium
falciparum rings below.
3. Select the Plasmodium vivax all stages slide (Slide Cassette 3: #17) from the slide loader.
Using the 10X objective identify the different stages and bring them into focus.
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4. Carefully work your way through all the objectives focusing with each one until you
reach the 60X objective and capture an image. Insert your image Plasmodium vivax
below.
Analysis:
5. Using the image from step 2, label the Plasmodium falciparum rings. Insert your image
below.
6. Using the image from step 4, label the different larval stages of Plasmodium vivax. Insert
your image below.
7. Utilizing the method from Exercise 1, determine the diameter of Plasmodium falciparum
rings and Plasmodium vivax rings.
8. Were there any difference between the rings produced by the 2 species. Does this
observation match your prediction form the pre-lab? Why or why not.
EXERCISE 5: Microscopic Examination of Ascaris Lumbricoides Eggs
Data Collection:
1. Select the Ascaris lumbricoides eggs slide (Slide Cassette 3: #3) from the slide loader.
Using the 10X objective, identify the cysts and bring them into focus.
2. Carefully work your way through all the objectives focusing with each one until you
reach the 60X objective and capture an image. Insert your images of Ascaris
lumbricoides eggs.
Analysis:
3. Using the image from step 2, label the eggs. Insert your images of Ascaris lumbricoides
eggs.
4. Were your predictions about the differences between an egg and cysts from the pre-lab
correct? Why or why not.
SUMMARY QUESTIONS:
1. What is the difference between a cyst and a trophozoite? Define each one.
Which one is less infective when found in a feces sample? Explain your answer.
2. Compare and contrast the life cycle of Taenia saginata and Plasmodium falciparum.
3. What is the impact of an infection by Plasmodium falciparum on red blood cells, blood
fluidity and blood circulation overall?
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4. You have been assigned to work on a Worldwide project with the World Health
Organization (WHO), the National Health Institute (NIH) and the Center for Disease
Control (CDC) aiming at reducing the prevalence of Schistomiasis (infection par the
parasite: Schistosomia mansoni) in the World.
Write a proposal describing:
a) The different strategies that might be developed and implemented to act at
different levels of the parasite cycle.
b) Provide the rationale behind each one of your strategies, their outcomes,
benefits and their limitations.
5. Research a different eukaryotic human parasite than the ones you studied in this lab.
Describe the mode of transmission, the host, the different stages of its cycle and ways
to prevent transmission to human.
6. Write a paragraph describing the latest initiatives and actions taken Worldwide to
eradicate Malaria.
What obstacles have been encountered so far by governmental and non-governmental
agencies?
Discuss pharmaceutical companies’ future plans.
7. One of your friends returned from a trip to Kenya and has been complaining in the last
few weeks from fatigue, dizziness and blood in feces.
8. Based on your knowledge of different parasites, what parasitology test will you
recommend him to do? And why?
9. Research more details on the following parasitic infections: leishmaniasis and
trypanosomiasis and contrast them in term of causative agents, signs, symptoms and
transmission vectors.
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For more information about NANSLO, visit www.wiche.edu/nanslo.
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