Answer:
A person standing on the ground is barely affected by surface gravity
Enhancers are eukaryotic DNA sequences that can be used to elevate transcription and have variable positions and orientations.
The right answer is vein (it contains blood and has valves).
The infra-cardiac veins of small and medium caliber possess this system of fight against gravity. The valves consist of a dense connective tissue, surmounted by endothelial cells, corresponding to a fold of the intima. They allow blood circulation in the sense organ / heart but prevent venous reflux.
Some reasons:
→ They're cheap and common animals.
→ They can be either a source of meat, skin (leather) or milk.
→ Farmers benefit a lot with them, since what they produce are things of everyday consumption.
→ You don't need to spend much to be able to have them (mostly only with land).
Hope it helped,
BioTeacher101
<span>the interference of two waves of equal frequency and opposite phase, resulting in their cancellation where the negative displacement of one always coincides with the positive displacement of the other.</span>
