Ans.
Cell-to-cell communication allows signalling of essential substances between the plant cells, which are surrounded by cell walls. The molecules used by plants for long-distance signalling are known as hormones, such as auxin, ethylene, and gibberelin.
These hormones are secreted by one plant cell and received by another plant cell, where it exerts it affect. Thus, the correct answer to be fill in the blank is 'option A). hormones.'
Answer:
In most tissues of the body, the response to hypoxia is vasodilation. By widening the blood vessels, the tissue allows greater perfusion. By contrast, in the lungs, the response to hypoxia is vasoconstriction.
Explanation:
Answer:
As the sweat evaporates off your skin, you cool down. Sweat is a great cooling system.
Explanation:
Answer:
“Geoneutrinos,” neutrinos that stream naturally from the Earth’s interior, are giving scientists the best direct evidence of what’s at work in the belly of the planet. Released by naturally occurring radioactive isotopes inside the Earth, geoneutrinos carry information about what makes the Earth’s insides hot; what elements make up the core of our planet and in what concentration and distribution; how the Earth’s mantle and tectonic plates move and interact; and how planets like our own form and evolve.
<span>Sun Belt is the southern region of the United States, it includes Florida, Texas, Arizona, and California. P</span><span>eople moved south to avoid the freezing winters of the North. </span><span>
Movement into the "sun belt" is an example of the population movement - migration. </span>