Giardia Intestinalis Is an Intestinal Parasite of Humans and Other

question 33

Multiple Choice

Giardia intestinalis is an intestinal parasite of humans and other mammals that causes intestinal ailments in most people who ingest the cysts. Upon ingestion, each cyst releases two motile cells, called "trophozoites". These attach to the small intestine's lining via a ventral adhesive disk. The trophozoites anaerobically metabolise glucose from the host's intestinal contents to produce ATP. Reproduction is completely asexual, occurring by longitudinal binary fission of trophozoites, with each daughter cell receiving two haploid nuclei (n = 5) . A trophozoite will often encyst as it passes into the large intestine by secreting around itself a case that is resistant to cold, heat, and dehydration. Infection usually occurs by drinking untreated water that contains cysts.
-
The mitosome of Giardia has no DNA within it. If it did contain DNA, then what predictions should we be able to make about its DNA?

• A) It is linear, has many introns, and is not associated with histone proteins.
• B) It is linear, has few introns, and is complexed with histone proteins.
• C) It is circular, has many introns, and is complexed with histone proteins.
• D) It is circular, has few introns, and is not associated with histone proteins.

---

Definitions:

Collecting Ducts

Collecting ducts are part of the kidney's nephrons, funneling urine from the nephrons to the ureters.

Renal Medulla

The inner region of the kidney, comprised of renal pyramids and involved in the concentration of urine.

Peritoneal Membrane

A serous membrane that forms the lining of the abdominal cavity or the peritoneum, involved in protecting abdominal organs.

Abdominopelvic Cavity

An anatomical space comprising the abdominal and pelvic cavities, containing vital organs including the stomach, liver, intestines, and reproductive structures.