Answer:
during the tadpole stage, they relie on the oxygen in the water to live, unlike frogs in the adult stage who can use the oxygen in the air on land
Explanation:
Answer:
d. all endothelial cells would be venous
Explanation:
The Notch signaling pathway is a cell signaling system which consist basically of 4 NOTCH genes ( NOTCH1, NOTCH2, NOTCH3, and NOTCH4) each of them having the information to build a particular cell membrane receptor protein.
It has been demonstrated in zebrafish embryos that Notch signaling are highly determinant factors during vascular development, and a key function of these genes was specifically to regulate the differentiation of arterial fate in endothelial cells.
Notch signaling-deficient embryos showed a loss of expression of arterial markers such as ephrinB2 from arterial vessels with an accompanying expansion of venous markers into normally arterial domains. In contrast, embryos in which Notch signaling had been ectopically activated, meaning an activation out of "proper" place (where not expected, e.g. venous endothelial), exhibited the contrary phenotype, this is a suppression of vein-specific markers with ectopic expression of arterial markers in venous vessels.
To summarize, when Notch is supressed (in this case inhibited with a specific Notch inhibitor) arterial fate of endothelium is not followed, and venous fate is stablished. Thus, endothelial cells (those expected to form venous tissues but also arterial ones) would specified as venous.
The answer is B. Genetic drift greatly affects small populations, but large populations can recover.
Temperature, pressure and composition.
There is one choice missing from this question:
<span>a. narcoleptic fits
b. nightmares
c. apnea episodes
d. night terrors*
The correct answer is "night terrors". Night terrors are intense feelings at the first half of non-REM sleep that is characterized by fear, horror, trembling, shaking. Night terrors are different from nightmares as there are physical effects carried out from night terrors upon waking up such as screaming, crying, and sudden movements.</span>