The life-cycle stages of the intestinal trematodes after the eggs are shed from the body via feces are best described as:
a. cercariae, miracidium larva, metacercariae, and redia.
b. redia, metacercariae, cercariae, and mira-cidium larva.
c. miracidium larva, redia, cercariae, and metacercariae.
d. metacercariae, miracidium larva, cercariae, and redia.
C
The adult worms are located in the small intestine, where they lay eggs, which may be embryo-nated or remain unembryonated until they are shed from the body via feces. The egg continues developing after reaching the water, and a ciliated, free-swimming miracidium larva is released. The miracidium enters a snail host and develops into a redia, followed by development into a tailed cercaria. The cercariae emerge from the snail and encyst as a metacercariae on water plants or fish.
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Are all point mutations SNPs?
A. Yes, because SNPs are single base pair changes of the DNA. B. Yes, because SNPs are random in their occurrence. C. No, because SNPs require a certain frequency in the population. D. No, because SNPs are mismatched base pairs.
_____ are not helpful for reconstructing evolutionary relationships because they do not show the evolutionary development of characters among groups
A. Analogies B. Homologies C. Similes D. Homilies
Honeybees must maintain specific temperatures to thrive. On hot days, the hive can quickly
overheat, so some bees will stand near the entrance and fan their wings to provide cool air currents into the hive. In winter, honeybees cluster together in their hives and vibrate their wings in a form of shivering to generate heat and maintain the hive at a constant temperature. This heating and cooling is a form of
a. homeostasis. b. evolution. c. competition. d. homology
Where do exocytic secretory vesicles originate?
a. endoplasmic reticulum b. plasma membrane c. the Golgi complex d. lysosomes e. microbodies