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.
All of the above, here's an explanation. The sun helps the water cycle due to evaporation which causes it to turn into a steam/gas. Now for wind, it's because the sun heats up the air and causes thermal energy which later turns into wind. And finally, weather, obviously the sun evaporates water which causes it to be rainy/drowsy.
Answer:
There is no actual way that the mantle could be...'exposed' or 'seen'. But scientists have managed to find multiple ways to analyze the mantle and it's actual existence by using multiple devices. The mantle is basically a 2,900 kilometers (1,802 miles) thick blocks of rocks and minerals underneath the crust(or the surface of the earth) , and makes up a whopping 84% of Earth's total volume.
Answer:
The geocentric model says that the earth is at the center of the cosmos or universe, and the planets, the sun and the moon, and the stars circles around it. The early heliocentric models consider the sun as the center, and the planets revolve around the sun.
Explanation:
The small cell extensions that beat to create an up-ward current are called microvilli.
<h3>What are microvilli?</h3>
Microvilli are small extensions which are found on the surface of the alveoli of the lungs.
The microvilli play an important role in the lungs as the help to remove particles and mucus that may obstruct the lungs as a result of the upward current they create in the lungs from their beating motion.
Therefore, the paralyzed small cell extensions that beat to create an up-ward current are called microvilli.
Learn more about lung microvilli at: brainly.com/question/12993303
#SPJ1
