Giardia intestinalis is an intestinal parasite of humans and other mammals that causes intestinal ailments in most people. It can infect people when they drink water contaminated with feces containing Giardia 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 metabolize 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.

The primary treatment for giardiasis (infection with Giardia), trichomoniasis (infection with Trichomonas vaginalis), and amoebic dysentery (infection with Entamoeba histolytica) is a drug marketed as Flagyl (generic name is metronidazole). The drug also kills anaerobic gut bacteria. Consequently, which of these are cues that Flagyl's mode of action has nothing to do with attacking or disabling flagella, as the drug's name might imply?

1. Flagyl would also harm the flagellated lining of the human intestine.
2. Entamoeba possesses pseudopods, not flagella, yet it is killed by Flagyl.
3. Not all anaerobic gut bacteria possess flagella, yet flagyl kills these bacteria.

2. Entamoeba possesses pseudopods, not flagella, yet it is killed by Flagyl.

3. Not all anaerobic gut bacteria possess flagella, yet flagyl kills these bacteria.

Explanation:

Metronidazole (brand name Flagyl), antibiotic and antiprotozoal medication is used to treat bacterial vaginosis, giardiasis, trichomoniasis, amebiasis, etc. When the metronidazole is partially reduced, it breaks the DNA of microbial cells and inhibits nucleic acid synthesis. This happens only in anaerobic bacteria and protozoans. The common side effects of metronidazole include nausea, dizziness, loss of appetite, diarrhea, weight loss, vomiting, abdominal pain, headache, metallic taste in the mouth, etc.

1) gene flow

- it is described as the transfer of genes from one population to another population so that frequency of gene is increased.

-a zebra migrates to join a different herd of zebras.

2) natural selection

- a mechanism of evolutionary change in which individuals with advantageous traits survive and reproduce whereas the others ( those that can not adapt) eliminate from the population.

-competition for sunlight leads to taller trees.

3) mutation

- permanent change in the nucleotide sequence of dna ( genetic material) that could have harmful or useful consequences.

-the dna of a snake changes to make its venom stronger.

4) genetic drift - it is a random phenomenon ( that occurs by chance such as fire) that results in change in the gene frequency in a small population.    

-a grassfire randomly sweeps through a population of buffalo and kills most of the animals.

explanation:

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.