NVCC BIO 150- 12wk Lecture Exam 3 questions
with verified answers
What are the 3 types of relationship between parasite, host or vector (if any)?
Ans✓✓-1. symbiosis= both host & parasite benefit. 2. Commensalism= only the
parasite benefits; no harm to host. 3. parasitism= only parasite benefits from
relationship; host will suffer & is harmed.
True or False. Entamoeba histolytica is an intestinal protozoa that causes amebic
dysentery and liver abscess. Ans✓✓-True
How many stages are in Entamoeba histolytica? Ans✓✓-The life cycle has two
stages1- The motile ameba (trophozoite) 2- The non-motile cyst
In humans, where is the first stage (trophozoite) found? (Entamoeba histolytica)
Ans✓✓-The 1st stage (trophozoite) found in intestinal and extra intestinal lesions
& in diarrheal stools.
Where is the 2nd stage ( cyst) (Entamoeba histolytica) likely to be found? Ans✓✓-
mostly found in non- diarrheal stool.
How many nuclei does the Entamoeba histolytic cyst have? Ans✓✓-2 nuclei in
the immature cyst, four nuclei in mature cyst, an important diagnostic criteria.
What is the vector for (chagas disease) American trypanosomiasis (Tyrpanosoma
cruzi)? Ans✓✓-An infected triatomine insect vector (or "kissing" bug) takes a
blood meal and releases trypomastigotes in its feces near the site of the bite
wound. Trypomastigotes enter the host through the bite wound or intact mucosal
membranes, such as the conjunctiva. Kissing bugs (Hemiptera: Reduviidae)
, List characteristics of Entamoeba histolytic trophozoite. Ans✓✓-Entamoeba
histolytic trophozoite is: 1. pear-shaped. 2. contains two nuclei. 3. has two suction
discs. 4. has 8 flagellates.
Entamoeba histolytic trophozoite attaches to .... Ans✓✓-The wall of intestines to
suck blood & obtain food.
When is a protozoa considered motile? Ans✓✓-When it has 1. Clilia. 2.
Pseudopods. 3. Flagella
How many flagella does Entamoeba histolytic trophozoite have? Ans✓✓-8
flagella - you can also say there are 4 pairs of flagella because they have the same
meaning.
What is the infectious stage of Entamoeba histolytica? Ans✓✓-A mature ovoid-
shaped cyst with four nuclei, via the oral route (ingested)
What is the route of infection for Entamoeba histolytic? Ans✓✓-A mature cyst
with four nuclei, via the oral route ....ingested by the human . can be
contaminated food, fly feces containing cysts attaches to food, hand to mouth
route, even anal-oral route.
True or False. Entamoeba histolytica is more common in young children and can
also be transmitted via a fly's feces on food. Ans✓✓-true
with verified answers
What are the 3 types of relationship between parasite, host or vector (if any)?
Ans✓✓-1. symbiosis= both host & parasite benefit. 2. Commensalism= only the
parasite benefits; no harm to host. 3. parasitism= only parasite benefits from
relationship; host will suffer & is harmed.
True or False. Entamoeba histolytica is an intestinal protozoa that causes amebic
dysentery and liver abscess. Ans✓✓-True
How many stages are in Entamoeba histolytica? Ans✓✓-The life cycle has two
stages1- The motile ameba (trophozoite) 2- The non-motile cyst
In humans, where is the first stage (trophozoite) found? (Entamoeba histolytica)
Ans✓✓-The 1st stage (trophozoite) found in intestinal and extra intestinal lesions
& in diarrheal stools.
Where is the 2nd stage ( cyst) (Entamoeba histolytica) likely to be found? Ans✓✓-
mostly found in non- diarrheal stool.
How many nuclei does the Entamoeba histolytic cyst have? Ans✓✓-2 nuclei in
the immature cyst, four nuclei in mature cyst, an important diagnostic criteria.
What is the vector for (chagas disease) American trypanosomiasis (Tyrpanosoma
cruzi)? Ans✓✓-An infected triatomine insect vector (or "kissing" bug) takes a
blood meal and releases trypomastigotes in its feces near the site of the bite
wound. Trypomastigotes enter the host through the bite wound or intact mucosal
membranes, such as the conjunctiva. Kissing bugs (Hemiptera: Reduviidae)
, List characteristics of Entamoeba histolytic trophozoite. Ans✓✓-Entamoeba
histolytic trophozoite is: 1. pear-shaped. 2. contains two nuclei. 3. has two suction
discs. 4. has 8 flagellates.
Entamoeba histolytic trophozoite attaches to .... Ans✓✓-The wall of intestines to
suck blood & obtain food.
When is a protozoa considered motile? Ans✓✓-When it has 1. Clilia. 2.
Pseudopods. 3. Flagella
How many flagella does Entamoeba histolytic trophozoite have? Ans✓✓-8
flagella - you can also say there are 4 pairs of flagella because they have the same
meaning.
What is the infectious stage of Entamoeba histolytica? Ans✓✓-A mature ovoid-
shaped cyst with four nuclei, via the oral route (ingested)
What is the route of infection for Entamoeba histolytic? Ans✓✓-A mature cyst
with four nuclei, via the oral route ....ingested by the human . can be
contaminated food, fly feces containing cysts attaches to food, hand to mouth
route, even anal-oral route.
True or False. Entamoeba histolytica is more common in young children and can
also be transmitted via a fly's feces on food. Ans✓✓-true
